S3F8278X-ET [SAMSUNG]

Microcontroller, 8-Bit, FLASH, SAM88RC CPU, 8MHz, CMOS, PQFP64;
S3F8278X-ET
型号: S3F8278X-ET
厂家: SAMSUNG    SAMSUNG
描述:

Microcontroller, 8-Bit, FLASH, SAM88RC CPU, 8MHz, CMOS, PQFP64

微控制器
文件: 总324页 (文件大小:2614K)
中文:  中文翻译
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S3C8275X/F8275X/C8278X  
/F8278X/C8274X/F8274X  
8-BIT CMOS  
MICROCONTROLLERS  
USER'S MANUAL  
Revision 1.4  
Important Notice  
The information in this publication has been carefully  
"Typical" parameters can and do vary in different  
applications. All operating parameters, including  
"Typicals" must be validated for each customer  
application by the customer's technical experts.  
checked and is believed to be entirely accurate at  
the time of publication. Samsung assumes no  
responsibility, however, for possible errors or  
omissions, or for any consequences resulting from  
the use of the information contained herein.  
Samsung products are not designed, intended, or  
authorized for use as components in systems  
intended for surgical implant into the body, for other  
applications intended to support or sustain life, or for  
any other application in which the failure of the  
Samsung product could create a situation where  
personal injury or death may occur.  
Samsung reserves the right to make changes in its  
products or product specifications with the intent to  
improve function or design at any time and without  
notice and is not required to update this  
documentation to reflect such changes.  
This publication does not convey to a purchaser of  
semiconductor devices described herein any license  
under the patent rights of Samsung or others.  
Should the Buyer purchase or use a Samsung  
product for any such unintended or unauthorized  
application, the Buyer shall indemnify and hold  
Samsung and its officers, employees, subsidiaries,  
affiliates, and distributors harmless against all  
claims, costs, damages, expenses, and reasonable  
attorney fees arising out of, either directly or  
indirectly, any claim of personal injury or death that  
may be associated with such unintended or  
unauthorized use, even if such claim alleges that  
Samsung was negligent regarding the design or  
manufacture of said product.  
Samsung makes no warranty, representation, or  
guarantee regarding the suitability of its products for  
any particular purpose, nor does Samsung assume  
any liability arising out of the application or use of  
any product or circuit and specifically disclaims any  
and all liability, including without limitation any  
consequential or incidental damages.  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X 8-Bit CMOS Microcontrollers  
User's Manual, Revision 1.4  
Publication Number: 21.4-S3-C8275X/F8275X/C8278X/F8278X/C8274X/F8274X-042007  
© 2007 Samsung Electronics  
All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in  
any form or by any means, electric or mechanical, by photocopying, recording, or otherwise, without the prior  
written consent of Samsung Electronics.  
Samsung Electronics' microcontroller business has been awarded full ISO-14001  
certification (BSI Certificate No. FM24653). All semiconductor products are  
designed and manufactured in accordance with the highest quality standards and  
objectives.  
Samsung Electronics Co., Ltd.  
San #24 Nongseo-Dong, Giheung-Gu  
Yongin-City, Gyeonggi-Do, Korea  
C.P.O. Box #37, Suwon 446-711  
TEL: (82)-(31)-209-5238  
FAX: (82)-(31)-209-6494  
Home-Page URL:  
Http://www.samsungsemi.com  
Printed in the Republic of Korea  
NOTIFICATION OF REVISIONS  
ORIGINATOR:  
Samsung Electronics, LSI Development Group, Gi-Heung, South Korea  
PRODUCT NAME:  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X 8-bit  
CMOS Microcontroller  
DOCUMENT NAME:  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X User's Manual,  
Revision1.4  
DOCUMENT NUMBER: 21.4-S3-C8275X/F8275X/C8278X/F8278X/C8274X/F8274X-042007  
EFFECTIVE DATE:  
SUMMARY:  
April, 2007  
As a result of additional product testing and evaluation, some specifications  
published in the S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X User's  
Manual, Revision 1, have been changed. These changes for  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X microcontroller,  
which are described in detail in the Revision Descriptions section below,  
are related to the followings:  
Chapter 16. Embedded flash memory interface  
Chapter 17. Electrical Data  
Chapter 7. Clock Circuit  
Chapter 2. Address Spaces  
DIRECTIONS:  
Please note the changes in your copy (copies) of the  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X User's Manual, Revision 1.  
Or, simply attach the Revision Descriptions of the next page to  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X User's Manual, Revision 1.  
REVISION HISTORY  
Revision  
Date  
Remark  
0
February, 2005  
April, 2005  
July, 2005  
Preliminary spec for internal release only.  
First edition. Reviewed by Finechips.  
Second edition. Reviewed by Finechips.  
Third edition. Reviewed by Finechips.  
Fourth edition. Reviewed by Finechips  
Fifth edition. Reviewed by Finechips  
1
1.1  
1.2  
1.3  
1.4  
August, 2005  
May, 2006  
April, 2007  
REVISION DESCRIPTIONS  
1. Electrical Data  
Table 17-12. A.C. Electrical Characteristics for Internal Flash ROM  
°
°
(TA  
=
25 C to + 85 C, VDD = 2.0 V to 3.6 V)  
Parameter  
Symbol  
Ftp  
Conditions  
Min  
30  
50  
10  
Typ  
Max  
Unit  
µs  
Programming time (1)  
Chip erasing time (2)  
Sector erasing time (3)  
Data access time  
Ftp1  
ms  
ms  
ns  
Ftp2  
FtRS  
25  
10,000(4)  
Number of writing/erasing  
FNwe  
Times  
NOTES:  
1. The programming time is the time during which one byte (8-bit) is programmed.  
2. The chip erasing time is the time during which all 16K byte block is erased.  
3. The sector erasing time is the time during which all 128 byte block is erased.  
4. Maximum number of writing/erasing is 10,000 times for full-flash(S3F8275) and 100 times for half-flash  
(S3F8278X/F8274X).  
5. The chip erasing is available in Tool Program Mode only.  
2. Condition of Operating Voltage  
Condition of operating voltage is modified “fx = 0 4.2MHz” to “fx = 0.4 4.2MHz” at 2.0V – 3.6V and  
“fx = 0 8MHz” to “fx = 0.4 8MHz” at 2.5V 3.6V in the page 17-2.  
3. CHAPTHER 16. Embedded Flash Memory Interface  
This chapter is modified for only S3F8275X.  
4. CHAPTHER 7. Clock Circuit  
The contents of OSCCON.7 should be changed “ 0 = Select normal circuit for sub oscillator” into “ 0 = Initial state”  
in the page 4-21 and Figure 7-10.  
It is added “NOTE: The OSCCON.7 should be maintained to “1”, during the sub oscillator operation.” In the page  
4-21 and Figure 7-10.  
The figure 7-7 is modified partly.  
Descriptions of Revision 1.4  
1. Smart Option Area  
The Figures are modified about smart option area. Those are “Figure 2-1. Program Memory Address Space” and  
“Figure 5-3. ROM Vector Address Area”.  
2. CHAPTHER 17. Electrical Data  
It is changed “VDD = 2.0 V to 3.6 V” into “VDD = 2.2 V to 3.6 V” in the Table 17-12.  
3. DEVICE NAME  
The device name is changed S3C8275/F8275/C8278/F8278/C8274/F8274 to  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X. The ‘X’ means ‘Commercial type’.  
Preface  
The S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X Microcontroller User's Manual is designed for  
application designers and programmers who are using the S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
microcontroller for application development. It is organized in two main parts:  
Part I Programming Model  
Part II Hardware Descriptions  
Part I contains software-related information to familiarize you with the microcontroller's architecture, programming  
model, instruction set, and interrupt structure. It has six chapters:  
Chapter 1  
Chapter 2  
Chapter 3  
Product Overview  
Address Spaces  
Addressing Modes  
Chapter 4  
Chapter 5  
Chapter 6  
Control Registers  
Interrupt Structure  
Instruction Set  
Chapter 1, "Product Overview," is a high-level introduction to  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X with general product descriptions, as well as detailed  
information about individual pin characteristics and pin circuit types.  
Chapter 2, "Address Spaces," describes program and data memory spaces, the internal register file, and register  
addressing. Chapter 2 also describes working register addressing, as well as system stack and user-defined  
stack operations.  
Chapter 3, "Addressing Modes," contains detailed descriptions of the addressing modes that are supported by the  
S3C8-series CPU.  
Chapter 4, "Control Registers," contains overview tables for all mapped system and peripheral control register  
values, as well as detailed one-page descriptions in a standardized format. You can use these easy-to-read,  
alphabetically organized, register descriptions as a quick-reference source when writing programs.  
Chapter 5, "Interrupt Structure," describes the S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X interrupt  
structure in detail and further prepares you for additional information presented in the individual hardware module  
descriptions in Part II.  
Chapter 6, "Instruction Set," describes the features and conventions of the instruction set used for all S3C8-series  
microcontrollers. Several summary tables are presented for orientation and reference. Detailed descriptions of  
each instruction are presented in a standard format. Each instruction description includes one or more practical  
examples of how to use the instruction when writing an application program.  
A basic familiarity with the information in Part I will help you to understand the hardware module descriptions in  
Part II. If you are not yet familiar with the S3C8-series microcontroller family and are reading this manual for the  
first time, we recommend that you first read Chapters 1–3 carefully. Then, briefly look over the detailed  
information in Chapters 4, 5, and 6. Later, you can reference the information in Part I as necessary.  
Part II "hardware Descriptions," has detailed information about specific hardware components of the  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X microcontroller. Also included in Part II are electrical,  
mechanical, Flash MCU, and development tools data. It has 14 chapters:  
Chapter 7  
Chapter 8  
Chapter 9  
Chapter 10  
Chapter 11  
Chapter 12  
Chapter 13  
Chapter 14  
Clock Circuit  
RESET and Power-Down  
I/O Ports  
Basic Timer  
Timer 1  
Watch Timer  
LCD Controller/Driver  
Serial I/O Interface  
Chapter 15  
Chapter 16  
Chapter 17  
Chapter 18  
Chapter 19  
Battery Level Detector  
Embedded Flash Memory Interface  
Electrical Data  
Mechanical Data  
S3F8275X/F8278X/F8274X  
Flash MCU  
Chapter 20  
Development Tools  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X MICROCONTROLLER  
iii  
Table of Contents  
Part I — Programming Model  
Chapter 1  
Product Overview  
S3C8-Series Microcontrollers .......................................................................................................................1-1  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X Microcontroller.......................................................1-1  
Flash..............................................................................................................................................................1-1  
Features ........................................................................................................................................................1-2  
Block Diagram...............................................................................................................................................1-3  
Pin Assignment .............................................................................................................................................1-4  
Pin Descriptions ............................................................................................................................................1-6  
Pin Circuits ....................................................................................................................................................1-8  
Chapter 2  
Address Spaces  
Overview........................................................................................................................................................2-1  
Program Memory (ROM)...............................................................................................................................2-2  
Smart Option.........................................................................................................................................2-3  
Register Architecture.....................................................................................................................................2-5  
Register Page Pointer (PP) ..................................................................................................................2-8  
Register Set 1.......................................................................................................................................2-10  
Register Set 2.......................................................................................................................................2-10  
Prime Register Space...........................................................................................................................2-11  
Working Registers ................................................................................................................................2-12  
Using the Register Points.....................................................................................................................2-13  
Register Addressing......................................................................................................................................2-15  
Common Working Register Area (C0H–CFH) .....................................................................................2-17  
4-Bit Working Register Addressing ......................................................................................................2-18  
8-Bit Working Register Addressing ......................................................................................................2-20  
System and User Stack.................................................................................................................................2-22  
Chapter 3  
Addressing Modes  
Overview........................................................................................................................................................3-1  
Register Addressing Mode (R)......................................................................................................................3-2  
Indirect Register Addressing Mode (IR)........................................................................................................3-3  
Indexed Addressing Mode (X).......................................................................................................................3-7  
Direct Address Mode (DA) ............................................................................................................................3-10  
Indirect Address Mode (IA) ...........................................................................................................................3-12  
Relative Address Mode (RA).........................................................................................................................3-13  
Immediate Mode (IM) ....................................................................................................................................3-14  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X MICROCONTROLLER  
v
Table of Contents (Continued)  
Chapter 4  
Control Registers  
Overview....................................................................................................................................................... 4-1  
Chapter 5  
Interrupt Structure  
Overview....................................................................................................................................................... 5-1  
Interrupt Types..................................................................................................................................... 5-2  
S3C8275X/C8278X/C8274X Interrupt Structure ................................................................................. 5-3  
Interrupt Vector Addresses .................................................................................................................. 5-4  
Enable/Disable Interrupt Instructions (EI, DI) ...................................................................................... 5-6  
System-Level Interrupt Control Registers............................................................................................ 5-6  
Interrupt Processing Control Points..................................................................................................... 5-7  
Peripheral Interrupt Control Registers ................................................................................................. 5-8  
System Mode Register (SYM) ............................................................................................................. 5-9  
Interrupt Mask Register (IMR) ............................................................................................................. 5-10  
Interrupt Priority Register (IPR)............................................................................................................ 5-11  
Interrupt Request Register (IRQ)......................................................................................................... 5-13  
Interrupt Pending Function Types........................................................................................................ 5-14  
Interrupt Source Polling Sequence...................................................................................................... 5-15  
Interrupt Service Routines ................................................................................................................... 5-15  
Generating Interrupt Vector Addresses ............................................................................................... 5-16  
Nesting of Vectored Interrupts............................................................................................................. 5-16  
Instruction Pointer (IP) ......................................................................................................................... 5-16  
Fast Interrupt Processing..................................................................................................................... 5-16  
Chapter 6  
Instruction Set  
Overview....................................................................................................................................................... 6-1  
Data Types........................................................................................................................................... 6-1  
Register Addressing............................................................................................................................. 6-1  
Addressing Modes ............................................................................................................................... 6-1  
Flags Register (FLAGS)....................................................................................................................... 6-6  
Flag Descriptions ................................................................................................................................. 6-7  
Instruction Set Notation........................................................................................................................ 6-8  
Condition Codes .................................................................................................................................. 6-12  
Instruction Descriptions........................................................................................................................ 6-13  
vi  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X MICROCONTROLLER  
Table of Contents (Continued)  
Part II Hardware Descriptions  
Chapter 7  
Clock Circuit  
Overview........................................................................................................................................................7-1  
System Clock Circuit ............................................................................................................................7-1  
Main Oscillator Circuits.........................................................................................................................7-2  
Sub Oscillator Circuits ..........................................................................................................................7-2  
Clock Status During Power-Down Modes ............................................................................................7-3  
System Clock Control Register (CLKCON)..........................................................................................7-4  
Clock Output Control Register (CLOCON)...........................................................................................7-5  
Oscillator Control Register (OSCCON) ................................................................................................7-6  
Switching the CPU Clock......................................................................................................................7-7  
Chapter 8  
RESET and Power-Down  
System Reset................................................................................................................................................8-1  
Overview...............................................................................................................................................8-1  
Normal Mode Reset Operation.............................................................................................................8-1  
Hardware Reset Values........................................................................................................................8-2  
Power-Down Modes......................................................................................................................................8-5  
Stop Mode ............................................................................................................................................8-5  
Idle Mode..............................................................................................................................................8-6  
Chapter 9  
I/O Ports  
Overview........................................................................................................................................................9-1  
Port Data Registers ..............................................................................................................................9-2  
port 0.....................................................................................................................................................9-3  
port 1.....................................................................................................................................................9-7  
port 2.....................................................................................................................................................9-11  
port 3.....................................................................................................................................................9-13  
Port 4 ....................................................................................................................................................9-15  
Port 5 ....................................................................................................................................................9-17  
Port 6 ....................................................................................................................................................9-19  
Chapter 10  
Basic Timer  
Overview........................................................................................................................................................10-1  
Basic Timer Control Register (BTCON) ...............................................................................................10-2  
Basic Timer Function Description.........................................................................................................10-3  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X MICROCONTROLLER  
vii  
Table of Contents (Continued)  
Chapter 11  
Timer 1  
One 16-bit Timer Mode (Timer 1)................................................................................................................. 11-1  
Overview .............................................................................................................................................. 11-1  
Function Description ............................................................................................................................ 11-1  
Two 8-bit Timers Mode (Timer A and B) ...................................................................................................... 11-4  
Overview .............................................................................................................................................. 11-4  
Function Description ............................................................................................................................ 11-4  
Chapter 12  
Watch Timer  
Overview....................................................................................................................................................... 12-1  
Watch Timer Control Register (WTCON) ............................................................................................ 12-2  
Watch Timer Circuit Diagram............................................................................................................... 12-3  
Chapter 13  
LCD Controller/Driver  
Overview....................................................................................................................................................... 13-1  
LCD Circuit Diagram............................................................................................................................ 13-2  
LCD RAM Address Area...................................................................................................................... 13-3  
LCD Control Register (LCON) ............................................................................................................. 13-4  
LCD Voltage Dividing Resistor ............................................................................................................ 13-5  
Common (COM) Signals...................................................................................................................... 13-6  
Segment (SEG) Signals....................................................................................................................... 13-6  
Chapter 14  
Serial I/O Interface  
Overview....................................................................................................................................................... 14-1  
Programming Procedure...................................................................................................................... 14-1  
SIO Control Registers (SIOCON) ........................................................................................................ 14-2  
SIO Pre-Scaler Register (SIOPS)........................................................................................................ 14-3  
SIO Block Diagram ....................................................................................................................................... 14-3  
Serial I/O Timing Diagram (SIO).......................................................................................................... 14-4  
Chapter 15  
Battery Level Detector  
Overview....................................................................................................................................................... 15-1  
Battery Level Detector Control Register (BLDCON)............................................................................ 15-2  
viii  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X MICROCONTROLLER  
Table of Contents (Continued)  
Embedded Flash Memory Interface  
Chapter 16  
Overview........................................................................................................................................................16-1  
User Program Mode......................................................................................................................................16-2  
Flash Memory Control Registers (User Program Mode)......................................................................16-2  
ISPTM (On-Board Programming) Sector .......................................................................................................16-5  
Sector Erase..................................................................................................................................................16-7  
Programming.................................................................................................................................................16-9  
Reading .........................................................................................................................................................16-11  
Hard Lock Protection.....................................................................................................................................16-12  
Chapter 17  
Electrical Data  
Overview........................................................................................................................................................17-1  
Chapter 18  
Mechanical Data  
Overview........................................................................................................................................................18-1  
Chapter 19  
S3F8275X/F8278X/F8274X Flash MCU  
Overview........................................................................................................................................................19-1  
Operating Mode Characteristics...........................................................................................................19-5  
Chapter 20  
Development Tools  
Overview........................................................................................................................................................20-1  
SHINE...................................................................................................................................................20-1  
SAMA Assembler..................................................................................................................................20-1  
SASM88................................................................................................................................................20-1  
HEX2ROM............................................................................................................................................20-1  
Target Boards.......................................................................................................................................20-1  
TB8275/8/4 Target Board.....................................................................................................................20-3  
SMDS2+ Selection (SAM8) ..................................................................................................................20-6  
Idle LED................................................................................................................................................20-6  
Stop LED ..............................................................................................................................................20-6  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X MICROCONTROLLER  
ix  
List of Figures  
Figure  
Title  
Page  
Number  
Number  
1-1  
1-2  
Block Diagram ............................................................................................................1-3  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X Pin Assignments  
(64-QFP-1420F) .........................................................................................................1-4  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X Pin Assignments  
1-3  
(64-LQFP-1010) .........................................................................................................1-5  
Pin Circuit Type A.......................................................................................................1-8  
Pin Circuit Type B (nRESET) .....................................................................................1-8  
Pin Circuit Type E-4 (P0, P1) .....................................................................................1-8  
Pin Circuit Type H-4 ...................................................................................................1-9  
Pin Circuit Type H-8 (P2.1–P2.7, P3).........................................................................1-9  
Pin Circuit Type H-9 (P4, P5, P6)...............................................................................1-10  
Pin Circuit Type H-10 (P2.0).......................................................................................1-11  
1-4  
1-5  
1-6  
1-7  
1-8  
1-9  
1-10  
2-1  
2-2  
2-3  
2-4  
2-5  
2-6  
2-7  
2-8  
Program Memory Address Space ..............................................................................2-2  
Smart Option...............................................................................................................2-3  
Internal Register File Organization (S3C8275X)........................................................2-6  
Internal Register File Organization (S3C8278X/C8274X)..........................................2-7  
Register Page Pointer (PP) ........................................................................................2-8  
Set 1, Set 2, Prime Area Register, and LCD Data Register Map...............................2-11  
8-Byte Working Register Areas (Slices).....................................................................2-12  
Contiguous 16-Byte Working Register Block .............................................................2-13  
Non-Contiguous 16-Byte Working Register Block .....................................................2-14  
16-Bit Register Pair ....................................................................................................2-15  
Register File Addressing ............................................................................................2-16  
Common Working Register Area................................................................................2-17  
4-Bit Working Register Addressing ............................................................................2-19  
4-Bit Working Register Addressing Example .............................................................2-19  
8-Bit Working Register Addressing ............................................................................2-20  
8-Bit Working Register Addressing Example .............................................................2-21  
Stack Operations........................................................................................................2-22  
2-9  
2-10  
2-11  
2-12  
2-13  
2-14  
2-15  
2-16  
2-17  
3-1  
3-2  
3-3  
3-4  
3-5  
3-6  
3-7  
3-8  
Register Addressing ...................................................................................................3-2  
Working Register Addressing.....................................................................................3-2  
Indirect Register Addressing to Register File.............................................................3-3  
Indirect Register Addressing to Program Memory .....................................................3-4  
Indirect Working Register Addressing to Register File ..............................................3-5  
Indirect Working Register Addressing to Program or Data Memory..........................3-6  
Indexed Addressing to Register File ..........................................................................3-7  
Indexed Addressing to Program or Data Memory with Short Offset..........................3-8  
Indexed Addressing to Program or Data Memory......................................................3-9  
Direct Addressing for Load Instructions .....................................................................3-10  
Direct Addressing for Call and Jump Instructions ......................................................3-11  
Indirect Addressing.....................................................................................................3-12  
Relative Addressing....................................................................................................3-13  
Immediate Addressing................................................................................................3-14  
3-9  
3-10  
3-11  
3-12  
3-13  
3-14  
4-1  
Register Description Format.......................................................................................4-4  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X MICROCONTROLLER  
xi  
List of Figures  
Figure  
Title  
Page  
Number  
Number  
5-1  
5-2  
5-3  
5-4  
5-5  
5-6  
5-7  
5-8  
5-9  
S3C8-Series Interrupt Types ..................................................................................... 5-2  
S3C8275X/C8278X/C8274X Interrupt Structure ....................................................... 5-3  
ROM Vector Address Area ........................................................................................ 5-4  
Interrupt Function Diagram........................................................................................ 5-7  
System Mode Register (SYM) ................................................................................... 5-9  
Interrupt Mask Register (IMR) ................................................................................... 5-10  
Interrupt Request Priority Groups.............................................................................. 5-11  
Interrupt Priority Register (IPR) ................................................................................. 5-12  
Interrupt Request Register (IRQ)............................................................................... 5-13  
6-1  
System Flags Register (FLAGS) ............................................................................... 6-6  
7-1  
7-2  
7-3  
7-4  
7-5  
7-6  
7-7  
7-8  
7-9  
7-10  
7-11  
Crystal/Ceramic Oscillator (fx)................................................................................... 7-2  
External Oscillator (fx)................................................................................................ 7-2  
RC Oscillator (fx)........................................................................................................ 7-2  
Crystal Oscillator (fxt)................................................................................................. 7-2  
External Oscillator (fxt)............................................................................................... 7-2  
System Clock Circuit Diagram................................................................................... 7-3  
System Clock Control Register (CLKCON) ............................................................... 7-4  
Clock Output Control Register (CLOCON)................................................................ 7-5  
Clock Output Block Diagram...................................................................................... 7-5  
Oscillator Control Register (OSCCON) ..................................................................... 7-6  
STOP Control Register (STPCON)............................................................................ 7-8  
9-1  
9-2  
9-3  
9-4  
9-5  
9-6  
9-7  
9-8  
S3C8275X/C8278X/C8274X I/O Port Data Register Format .................................... 9-2  
Port 0 High-Byte Control Register (P0CONH)........................................................... 9-4  
Port 0 Low-Byte Control Register (P0CONL) ............................................................ 9-4  
Port 0 Pull-up Control Register (P0PUR) .................................................................. 9-5  
External Interrupt Control Register, Low Byte (EXTICONL)...................................... 9-5  
External Interrupt Pending Register (EXTIPND) ....................................................... 9-6  
Port 1 High-Byte Control Register (P1CONH)........................................................... 9-8  
Port 1 Low-Byte Control Register (P1CONL) ............................................................ 9-8  
Port 1 Pull-up Control Register (P1PUR) .................................................................. 9-9  
External Interrupt Control Register, High Byte (EXTICONH) .................................... 9-9  
External Interrupt Control Register, Low Byte (EXTICONL)...................................... 9-10  
External Interrupt Pending Register (EXTIPND) ....................................................... 9-10  
Port 2 High-byte Control Register (P2CONH) ........................................................... 9-11  
Port 2 Low-byte Control Register (P2CONL)............................................................. 9-12  
Port 2 Pull-up Control Register (P2PUR) .................................................................. 9-12  
Port 3 High Byte Control Register (P3CONH)........................................................... 9-13  
Port 3 Low Byte Control Register (P3CONL) ............................................................ 9-14  
Port 3 Pull-up Control Register (P3PUR) .................................................................. 9-14  
9-9  
9-10  
9-11  
9-12  
9-13  
9-14  
9-15  
9-16  
9-17  
9-18  
xii  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X MICROCONTROLLER  
List of Figures (Continued)  
Page  
Title  
Page  
Number  
Number  
9-19  
9-20  
9-21  
9-22  
9-23  
Port 4 High-Byte Control Register (P4CONH) ...........................................................9-15  
Port 4 Low-Byte Control Register (P4CONL).............................................................9-16  
Port 5 High-Byte Control Register (P5CONH) ...........................................................9-17  
Port 5 Low-Byte Control Register (P5CONL).............................................................9-18  
Port 6 Control Register (P6CON)...............................................................................9-19  
10-1  
10-2  
Basic Timer Control Register (BTCON) .....................................................................10-2  
Basic Timer Block Diagram........................................................................................10-4  
11-1  
11-2  
11-3  
11-4  
11-5  
11-6  
Timer 1/A Control Register (TACON).........................................................................11-2  
Timer 1 Block Diagram (One 16-bit Mode) ................................................................11-3  
Timer 1/A Control Register (TACON).........................................................................11-5  
Timer B Control Register (TBCON)............................................................................11-6  
Timer A Block Diagram(Two 8-bit Timers Mode).......................................................11-7  
Timer B Block Diagram (Two 8-bit Timers Mode)......................................................11-8  
12-1  
12-2  
Watch Timer Control Register (WTCON)...................................................................12-2  
Watch Timer Circuit Diagram .....................................................................................12-3  
13-1  
13-2  
13-3  
13-4  
13-5  
13-6  
13-7  
13-8  
13-9  
LCD Function Diagram...............................................................................................13-1  
LCD Circuit Diagram...................................................................................................13-2  
LCD Display Data RAM Organization ........................................................................13-3  
LCD Control Register (LCON)....................................................................................13-4  
Internal Voltage Dividing Resistor Connection...........................................................13-5  
Select/No-Select Signals in Static Display Mode.......................................................13-6  
Select/No-Select Signal in 1/2 Duty, 1/2 Bias Display Mode .....................................13-7  
Select/No-Select Signal in 1/3 Duty, 1/3 Bias Display Mode .....................................13-7  
LCD Signals and Wave Forms Example in 1/4 Duty, 1/3 Bias Display Mode............13-8  
14-1  
14-2  
14-3  
14-4  
14-5  
Serial I/O Module Control Register (SIOCON)...........................................................14-2  
SIO Prescaler Register (SIOPS) ................................................................................14-3  
SIO Functional Block Diagram ...................................................................................14-3  
Serial I/O Timing in Transmit/Receive Mode (Tx at falling, SIOCON.4 = 0) ..............14-4  
Serial I/O Timing in Transmit/Receive Mode (Tx at rising, SIOCON.4 = 1)...............14-4  
15-1  
15-2  
Block Diagram for Voltage Level Detect.....................................................................15-1  
Battery Level Detect Circuit and Control Register......................................................15-2  
16-1  
16-2  
16-3  
16-4  
16-5  
16-6  
Flash Memory Control Register (FMCON).................................................................16-2  
Flash Memory User-Programming Enable Register (FMUSR)..................................16-3  
Flash Memory Sector Address Register, High Byte (FMSECH)................................16-4  
Flash Memory Sector Address Register, Low Byte (FMSECL) .................................16-4  
Program Memory Address Space ..............................................................................16-5  
Sector Configurations in User Program Mode ...........................................................16-7  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X MICROCONTROLLER  
xiii  
List of Figures (Concluded)  
Page  
Title  
Page  
Number  
Number  
17-1  
17-2  
17-3  
17-4  
17-5  
17-6  
17-7  
Stop Mode Release Timing When Initiated by an External Interrupt......................... 17-5  
Stop Mode Release Timing When Initiated by a RESET .......................................... 17-6  
Input Timing for External Interrupts ........................................................................... 17-7  
Input Timing for RESET............................................................................................. 17-8  
Serial Data Transfer Timing....................................................................................... 17-8  
LVR (Low Voltage Reset) Timing .............................................................................. 17-9  
Clock Timing Measurement at XIN............................................................................. 17-11  
17-8  
17-9  
Clock Timing Measurement at XTIN .......................................................................... 17-12  
Operating Voltage Range .......................................................................................... 17-13  
18-1  
18-2  
64-Pin QFP Package Dimensions (64-QFP-1420F) ................................................. 18-1  
64-Pin LQFP Package Dimensions (64-LQFP-1010)................................................ 18-2  
19-1  
19-2  
19-3  
S3F8275X/F8278X/F8274X Pin Assignments (64-QFP-1420F)............................... 19-2  
S3F8275X/F8278X/F8274X Pin Assignments (64-LQFP-1010) ............................... 19-3  
Operating Voltage Range .......................................................................................... 19-7  
20-1  
20-2  
20-3  
20-4  
SMDS Product Configuration (SMDS2+)................................................................... 20-2  
TB8275/8/4 Target Board Configuration.................................................................... 20-3  
40-Pin Connectors (J101, J102) for TB8275/8/4....................................................... 20-7  
S3E8270 Cables for 64-QFP Package...................................................................... 20-7  
xiv  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X MICROCONTROLLER  
List of Tables  
Table  
Title  
Page  
Number  
Number  
1-1  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X Pin Descriptions .................1-6  
2-1  
2-2  
S3C8275X Register Type Summary..........................................................................2-5  
S3C8278X/C8274X Register Type Summary............................................................2-5  
4-1  
4-2  
4-3  
Set 1 Registers...........................................................................................................4-1  
Set 1, Bank 0 Registers..............................................................................................4-2  
Set 1, Bank 1 Registers..............................................................................................4-3  
5-1  
5-2  
5-3  
Interrupt Vectors.........................................................................................................5-5  
Interrupt Control Register Overview...........................................................................5-6  
Interrupt Source Control and Data Registers.............................................................5-8  
6-1  
6-2  
6-3  
6-4  
6-5  
6-6  
Instruction Group Summary .......................................................................................6-2  
Flag Notation Conventions.........................................................................................6-8  
Instruction Set Symbols..............................................................................................6-8  
Instruction Notation Conventions ...............................................................................6-9  
Opcode Quick Reference...........................................................................................6-10  
Condition Codes.........................................................................................................6-12  
8-1  
8-2  
8-3  
S3C8275X/C8278X/C8274X Set 1 Register and Values After RESET.....................8-2  
S3C8275X/C8278X/C8274X Set 1, Bank 0 Register Values After RESET...............8-3  
S3C8275X/C8278X/C8274X Set 1, Bank 1 Register Values After RESET...............8-4  
9-1  
9-2  
S3C8275X/C8278X/C8274X Port Configuration Overview .......................................9-1  
Port Data Register Summary .....................................................................................9-2  
13-1  
15-1  
LCD Clock Signal Frame Frequency .........................................................................13-3  
BLDCON Value and Detection Level .........................................................................15-2  
16-1  
16-2  
ISP Sector Size ..........................................................................................................16-6  
Reset Vector Address ................................................................................................16-6  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X MICROCONTROLLER  
xv  
List of Tables (Continued)  
Table  
Title  
Page  
Number  
Number  
17-1  
17-2  
17-3  
17-4  
17-5  
17-6  
17-7  
17-8  
17-9  
17-10  
17-11  
17-12  
Absolute Maximum Ratings........................................................................................17-2  
D.C. Electrical Characteristics....................................................................................17-2  
Data Retention Supply Voltage in Stop Mode............................................................17-5  
Input/Output Capacitance...........................................................................................17-6  
A.C. Electrical Characteristics ....................................................................................17-7  
Battery Level Detector Electrical Characteristics .......................................................17-9  
LVR (Low Voltage Reset) Electrical Characteristics ..................................................17-9  
Main Oscillation Characteristics .................................................................................17-10  
Sub Oscillation Characteristics...................................................................................17-10  
Main Oscillation Stabilization Time.............................................................................17-11  
Sub Oscillation Stabilization Time ..............................................................................17-12  
A.C. Electrical Characteristics for Internal Flash ROM ..............................................17-13  
19-1  
19-2  
Descriptions of Pins Used to Read/Write the Flash ROM..........................................19-4  
Comparison of S3F8275X/F8278X/F8274X and  
S3C8275X/C8278X/C8274X Features.......................................................................19-4  
Operating Mode Selection Criteria .............................................................................19-5  
D.C. Electrical Characteristics....................................................................................19-6  
19-3  
19-4  
20-1  
20-2  
20-3  
20-4  
20-5  
20-6  
Power Selection Settings for TB8275/8/4...................................................................20-4  
Main-clock Selection Settings for TB8275/8/4............................................................20-4  
Select Smart Option Source Setting for TB8275/8/4..................................................20-5  
Smart Option Switch Settings for TB8275/8/4............................................................20-5  
Device Selection Settings for TB8275/8/4..................................................................20-6  
The SMDS2+ Tool Selection Setting..........................................................................20-6  
xvi  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X MICROCONTROLLER  
List of Programming Tips  
Description  
Chapter 2:  
Page  
Number  
Address Spaces  
Using the Page Pointer for RAM Clear (Page 0, Page 1) ........................................................................2-9  
Setting the Register Pointers....................................................................................................................2-13  
Using the RPs to Calculate the Sum of a Series of Registers .................................................................2-14  
Addressing the Common Working Register Area.....................................................................................2-18  
Standard Stack Operations Using PUSH and POP .................................................................................2-23  
Chapter 5: Interrupt Structure  
How to clear an interrupt pending bit........................................................................................................5-15  
Chapter 7: Clock Circuit  
Switching the CPU Clock..........................................................................................................................7-7  
Chapter 16:  
Embedded Flash Memory Interface  
Sector Erase.............................................................................................................................................16-8  
Program ....................................................................................................................................................16-10  
Reading.....................................................................................................................................................16-11  
Hard Lock Protection ................................................................................................................................16-12  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X MICROCONTROLLER  
xvii  
List of Register Descriptions  
Register  
Identifier  
Full Register Name  
Page  
Number  
BLDCON  
BTCON  
CLKCON  
CLOCON  
EXTICONH  
EXTICONL  
EXITPND  
FLAGS  
FMCON  
FMSECH  
FMSECL  
FMUSR  
IMR  
Battery Level Detector Control Register ....................................................................4-5  
Basic Timer Control Register .....................................................................................4-6  
System Clock Control Register ..................................................................................4-7  
Clock Output Control Register ...................................................................................4-8  
External Interrupt Control Register (High Byte) .........................................................4-9  
External Interrupt Control Register (Low Byte) ..........................................................4-10  
External Interrupt Pending Register...........................................................................4-11  
System Flags Register ...............................................................................................4-12  
Flash Memory Control Register .................................................................................4-13  
Flash Memory Sector Address Register (High Byte).................................................4-14  
Flash Memory Sector Address Register (Low Byte)..................................................4-14  
Flash Memory User Programming Enable Register ..................................................4-15  
Interrupt Mask Register..............................................................................................4-16  
Instruction Pointer (High Byte) ...................................................................................4-17  
Instruction Pointer (Low Byte)....................................................................................4-17  
Interrupt Priority Register ...........................................................................................4-18  
Interrupt Request Register.........................................................................................4-19  
LCD Control Register.................................................................................................4-20  
Oscillator Control Register .........................................................................................4-21  
Port 0 Control Register (High Byte)............................................................................4-22  
Port 0 Control Register (Low Byte) ............................................................................4-23  
Port 0 Pull-Up Control Register..................................................................................4-24  
Port 1 Control Register (High Byte)............................................................................4-25  
Port 1 Control Register (Low Byte) ............................................................................4-26  
Port 1 Pull-up Control Register ..................................................................................4-27  
Port 2 Control Register (High Byte)............................................................................4-28  
Port 2 Control Register (Low Byte) ............................................................................4-29  
Port 2 Pull-up Control Register ..................................................................................4-30  
Port 3 Control Register (High Byte)............................................................................4-31  
Port 3 Control Register (Low Byte) ............................................................................4-32  
Port 3 Pull-up Control Register ..................................................................................4-33  
Port 4 Control Register (High Byte)............................................................................4-34  
Port 4 Control Register (Low Byte) ............................................................................4-35  
Port 5 Control Register (High Byte)............................................................................4-36  
Port 5 Control Register (Low Byte) ............................................................................4-37  
Port 6 Control Register...............................................................................................4-38  
Register Page Pointer ................................................................................................4-39  
Register Pointer 0.......................................................................................................4-40  
Register Pointer 1.......................................................................................................4-40  
SIO Control Register ..................................................................................................4-41  
Stack Pointer (High Byte)...........................................................................................4-42  
Stack Pointer (Low Byte)............................................................................................4-42  
Stop Control Register.................................................................................................4-43  
System Mode Register...............................................................................................4-44  
Timer 1/A Control Register.........................................................................................4-45  
Timer B Control Register............................................................................................4-46  
Watch Timer Control Register....................................................................................4-47  
IPH  
IPL  
IPR  
IRQ  
LCON  
OSCCON  
P0CONH  
P0CONL  
P0PUR  
P1CONH  
P1CONL  
P1PUR  
P2CONH  
P2CONL  
P2PUR  
P3CONH  
P3CONL  
P3PUR  
P4CONH  
P4CONL  
P5CONH  
P5CONL  
P6CON  
PP  
RP0  
RP1  
SIOCON  
SPH  
SPL  
STPCON  
SYM  
TACON  
TBCON  
WTCON  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X MICROCONTROLLER  
xix  
List of Instruction Descriptions  
Instruction  
Mnemonic  
Full Register Name  
Page  
Number  
ADC  
ADD  
AND  
BAND  
BCP  
BITC  
BITR  
BITS  
BOR  
BTJRF  
BTJRT  
BXOR  
CALL  
CCF  
CLR  
COM  
CP  
Add with Carry............................................................................................................6-14  
Add .............................................................................................................................6-15  
Logical AND ...............................................................................................................6-16  
Bit AND.......................................................................................................................6-17  
Bit Compare ...............................................................................................................6-18  
Bit Complement..........................................................................................................6-19  
Bit Reset.....................................................................................................................6-20  
Bit Set.........................................................................................................................6-21  
Bit OR.........................................................................................................................6-22  
Bit Test, Jump Relative on False ...............................................................................6-23  
Bit Test, Jump Relative on True.................................................................................6-24  
Bit XOR.......................................................................................................................6-25  
Call Procedure............................................................................................................6-26  
Complement Carry Flag.............................................................................................6-27  
Clear...........................................................................................................................6-28  
Complement...............................................................................................................6-29  
Compare.....................................................................................................................6-30  
Compare, Increment, and Jump on Equal .................................................................6-31  
Compare, Increment, and Jump on Non-Equal .........................................................6-32  
Decimal Adjust ...........................................................................................................6-33  
Decrement..................................................................................................................6-35  
Decrement Word ........................................................................................................6-36  
Disable Interrupts .......................................................................................................6-37  
Divide (Unsigned).......................................................................................................6-38  
Decrement and Jump if Non-Zero..............................................................................6-39  
Enable Interrupts........................................................................................................6-40  
Enter...........................................................................................................................6-41  
Exit..............................................................................................................................6-42  
Idle Operation.............................................................................................................6-43  
Increment ...................................................................................................................6-44  
Increment Word..........................................................................................................6-45  
Interrupt Return ..........................................................................................................6-46  
Jump...........................................................................................................................6-47  
Jump Relative.............................................................................................................6-48  
Load............................................................................................................................6-49  
Load Bit ......................................................................................................................6-51  
CPIJE  
CPIJNE  
DA  
DEC  
DECW  
DI  
DIV  
DJNZ  
EI  
ENTER  
EXIT  
IDLE  
INC  
INCW  
IRET  
JP  
JR  
LD  
LDB  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X MICROCONTROLLER  
xxi  
List of Instruction Descriptions (Continued)  
Instruction  
Mnemonic  
Full Register Name  
Page  
Number  
LDC/LDE  
LDCD/LDED  
LDCI/LDEI  
LDCPD/LDEPD  
LDCPI/LDEPI  
LDW  
Load Memory..............................................................................................................6-52  
Load Memory and Decrement....................................................................................6-54  
Load Memory and Increment......................................................................................6-55  
Load Memory with Pre-Decrement.............................................................................6-56  
Load Memory with Pre-Increment ..............................................................................6-57  
Load Word ..................................................................................................................6-58  
Multiply (Unsigned).....................................................................................................6-59  
Next.............................................................................................................................6-60  
No Operation ..............................................................................................................6-61  
Logical OR..................................................................................................................6-62  
Pop from Stack ...........................................................................................................6-63  
Pop User Stack (Decrementing).................................................................................6-64  
Pop User Stack (Incrementing) ..................................................................................6-65  
Push to Stack..............................................................................................................6-66  
Push User Stack (Decrementing)...............................................................................6-67  
Push User Stack (Incrementing) ................................................................................6-68  
Reset Carry Flag.........................................................................................................6-69  
Return.........................................................................................................................6-70  
Rotate Left ..................................................................................................................6-71  
Rotate Left through Carry...........................................................................................6-72  
Rotate Right................................................................................................................6-73  
Rotate Right through Carry.........................................................................................6-74  
Select Bank 0..............................................................................................................6-75  
Select Bank 1..............................................................................................................6-76  
Subtract with Carry .....................................................................................................6-77  
Set Carry Flag.............................................................................................................6-78  
Shift Right Arithmetic ..................................................................................................6-79  
Set Register Pointer....................................................................................................6-80  
Stop Operation............................................................................................................6-81  
Subtract ......................................................................................................................6-82  
Swap Nibbles..............................................................................................................6-83  
Test Complement under Mask ...................................................................................6-84  
Test under Mask.........................................................................................................6-85  
Wait for Interrupt.........................................................................................................6-86  
Logical Exclusive OR..................................................................................................6-87  
MULT  
NEXT  
NOP  
OR  
POP  
POPUD  
POPUI  
PUSH  
PUSHUD  
PUSHUI  
RCF  
RET  
RL  
RLC  
RR  
RRC  
SB0  
SB1  
SBC  
SCF  
SRA  
SRP/SRP0/SRP1  
STOP  
SUB  
SWAP  
TCM  
TM  
WFI  
XOR  
xxii  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X MICROCONTROLLER  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
PRODUCT OVERVIEW  
1
PRODUCT OVERVIEW  
S3C8-SERIES MICROCONTROLLERS  
Samsung's S3C8 series of 8-bit single-chip CMOS microcontrollers offers a fast and efficient CPU, a wide range  
of integrated peripherals, and various mask-programmable ROM sizes. Among the major CPU features are:  
Efficient register-oriented architecture  
Selectable CPU clock sources  
Idle and Stop power-down mode release by interrupt or reset  
Built-in basic timer with watchdog function  
A sophisticated interrupt structure recognizes up to eight interrupt levels. Each level can have one or more  
interrupt sources and vectors. Fast interrupt processing (within a minimum of four CPU clocks) can be assigned to  
specific interrupt levels.  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X MICROCONTROLLER  
The S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X single-chip CMOS microcontrollers are fabricated  
using the highly advanced CMOS process, based on Samsung's latest CPU architecture.  
The S3C8275X/C8278X/C8274X is a microcontroller with a 16/8/4K-byte mask-programmable ROM embedded.  
The S3F8275X/F8278X/F8274X is a microcontroller with a 16/8/4K-byte flash ROM embedded.  
Using a proven modular design approach, Samsung engineers have successfully developed the  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X by integrating the following peripheral modules with the  
powerful SAM8 core:  
Seven programmable I/O ports, including six 8-bit ports and one 4-bit port, for a total of 52 pins.  
Eight bit-programmable pins for external interrupts.  
One 8-bit basic timer for oscillation stabilization and watchdog function (system reset).  
Two 8-bit timer/counter with selectable operating modes.  
Watch timer for real time  
FLASH  
The S3F8275X/F8278X/F8274X are FLASH version of the S3C8275X/C8278X/C8274X microcontroller. The  
S3F8275X/F8278X/F8274X microcontroller has an on-chip FLASH ROM instead of a masked ROM. The  
S3F8275X/F8278X/F8274X is comparable to the S3C8275X/C8278X/C8274X, both in function and in pin  
configuration. The S3F8275X only is a full flash. The full flash means that data can be written into the program  
ROM by an instruction.  
1-1  
PRODUCT OVERVIEW  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
FEATURES  
CPU  
Watch Timer  
SAM88RC CPU core  
Memory  
Program Memory(ROM)  
Interval time: 3.91mS, 0.25S, 0.5S, and 1S  
at 32.768 kHz  
0.5/1/2/4 kHz Selectable buzzer output  
LCD Controller/Driver  
- 16K×8 bits program  
memory(S3C8275X/F8275X)  
- 8K×8 bits program  
memory(S3C8278X/F8278X)  
- 4K×8 bits program  
memory(S3C8274X/F8274X)  
- Internal flash memory(Program memory)  
Sector size: 128 Bytes  
32 segments and 4 common terminals  
Static, 1/2 duty, 1/3 duty, and 1/4 duty selectable  
Internal resistor circuit for LCD bias  
8-bit Serial I/O Interface  
8-bit transmit/receive mode  
8-bit receive mode  
10 Years data retention  
Fast programming time:  
+ Chip erase: 50ms  
LSB-first or MSB-first transmission selectable  
Internal or External clock source  
Battery Level Detector  
+ Sector erase: 10ms  
+ Byte program: 30us  
3-criteria voltage selectable (2.2V, 2.4V, 2.8V)  
User programmable by ‘LDC’ instruction  
Endurance: 10,000 erase/program cycles  
Sector(128-bytes) erase available  
Byte programmable  
External serial programming support  
Expandable OBPTM(On board program)  
sector  
En/Disable by software for current consumption  
source  
Low Voltage Reset (LVR)  
Criteria voltage: 2.2V  
En/Disable by smart option (ROM address: 3FH)  
Two Power-Down Modes  
Idle: only CPU clock stops  
Data Memory (RAM)  
- Including LCD display data memory  
- 544 × 8 bits data memory(S3C8275X/F8275X)  
- 288 × 8 bits data memory(S3C8278X/F8278X)  
- 288 × 8 bits data memory(S3C8274X/F8274X)  
Stop: selected system clock and CPU clock stop  
Oscillation Sources  
Crystal, ceramic, or RC for main clock  
Main clock frequency: 0.4 MHz 8 MHz  
32.768 kHz crystal for sub clock  
Instruction Set  
78 instructions  
Instruction Execution Times  
500nS at 8 MHz fx(minimum)  
Operating Voltage Range  
Idle and Stop instructions added for power-down  
modes  
52 I/O Pins  
I/O: 16 pins  
I/O: 36 pins (Sharing with LCD signal outputs)  
2.0 V to 3.6 V at 0.4 4.2 MHz  
2.5 V to 3.6 V at 0.4 8.0 MHz  
Interrupts  
Operating Temperature Range  
25 °C to +85 °C  
Package Type  
8 interrupt levels and 12 interrupt sources  
Fast interrupt processing feature  
8-Bit Basic Timer  
64-QFP-1420F, 64-LQFP-1010  
Watchdog timer function  
4 kinds of clock source  
Smart Option  
Low Voltage Reset(LVR) level and  
enable/disable are at your hardwired option  
(ROM address 3FH)  
Two 8-Bit Timer/Counters  
Programmable interval timer  
External event counter function  
Configurable as one 16-bit timer/counters  
ISP related option selectable  
(ROM address 3EH)  
1-2  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
PRODUCT OVERVIEW  
BLOCK DIAGRAM  
Watchdog  
Timer  
X
XTIN  
IN  
X
OUT  
TAOUT/P0.4  
V
REG  
8-Bit Timer/  
Counter A  
8-Bit Timer/  
Counter B  
nRESET  
XTOUT  
16-Bit  
Timer/  
Counter 1  
T1CLK/P0.3  
Basic Timer  
TBOUT/P0.5  
Low Voltage  
Reset  
P0.0/INT0  
P0.1/INT1  
P0.2/INT2  
Clock Out  
Block  
CLKOUT/P0.6  
Port I/O and Interrupt Control  
P0.3/T1CLK  
P0.4/TAOUT  
P0.5/TBOUT  
P0.6/CLKOUT  
P0.7/BUZ  
Battery Level  
Detector  
V
BLDREF/  
I/O Port 0  
P2.0/SEG31  
Watch Timer  
BUZ/P0.7  
COM0-COM3/P6.0-P6.3  
SEG0-SEG7/P5.7-P5.0  
SEG8-SEG15/P4.7-P4.0  
P1.0/SCK  
P1.1/SO  
P1.2/SI  
P1.3/INT3  
P1.4/INT4  
P1.5/INT5  
P1.6/INT6  
P1.7/INT7  
SAM88RC CPU  
LCD  
Driver  
SEG16-SEG23/P3.7-P3.0  
SEG24-SEG30/P2.7-P2.1  
SEG31/P2.0/VBLDREF  
VLC0-VLC2  
I/O Port 1  
544/288 Byte  
Register File  
16/8/4-Kbyte  
ROM  
P1.0/SCK  
P1.1/SO  
P1.2/SI  
P2.0/SEG31/VBLDREF  
I/O Port 2  
I/O Port 3  
I/O Port 4  
SIO  
P2.1-P2.7/SEG30-SEG24  
P6.0-P6.3/  
COM0-COM3  
I/O Port 6  
I/O Port 5  
P3.0-P3.7/SEG23-SEG16  
P4.0-P4.7/SEG15-SEG8  
P5.0-P5.7/  
SEG7-SEG0  
Figure 1-1. Block Diagram  
1-3  
PRODUCT OVERVIEW  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
PIN ASSIGNMENT  
SEG0/P5.7  
1
2
3
4
5
6
7
8
51  
50  
49  
48  
47  
46  
45  
44  
43  
42  
41  
40  
39  
38  
37  
36  
35  
34  
33  
SEG14/P4.1  
SEG15/P4.0  
SEG16/P3.7  
SEG17/P3.6  
SEG18/P3.5  
SEG19/P3.4  
SEG20/P3.3  
SEG21/P3.2  
SEG22/P3.1  
SEG23/P3.0  
SEG24/P2.7  
SEG25/P2.6  
SEG26/P2.5  
SEG27/P2.4  
SEG28/P2.3  
SEG29/P2.2  
SEG30/P2.1  
SEG31/P2.0/VBLDREF  
P1.7/INT7  
COM0/P6.0  
COM1/P6.1  
COM2/P6.2  
COM3/P6.3  
VLC0  
VLC1  
VLC2  
VDD  
VSS  
XOUT  
XIN  
TEST  
XTIN  
S3C8275X/F8275X  
S3C8278X/F8278X  
S3C8274X/F8274X  
9
10  
11  
12  
13  
14  
15  
16  
17  
18  
19  
(64-QFP-1420F)  
XTOUT  
nRESET  
VREG  
P0.0/INT0  
P0.1/INT1  
Figure 1-2. S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X Pin Assignments (64-QFP-1420F)  
1-4  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
PRODUCT OVERVIEW  
SEG0/P5.7  
COM0/P6.0  
COM1/P6.1  
COM2/P6.2  
COM3/P6.3  
VLC0  
1
2
3
4
5
6
7
8
48  
47  
46  
45  
44  
43  
42  
41  
40  
39  
38  
37  
36  
35  
34  
33  
SEG17/P3.6  
SEG18/P3.5  
SEG19/P3.4  
SEG20/P3.3  
SEG21/P3.2  
SEG22/P3.1  
SEG23/P3.0  
SEG24/P2.7  
SEG25/P2.6  
SEG26/P2.5  
SEG27/P2.4  
SEG28/P2.3  
SEG29/P2.2  
SEG30/P2.1  
SEG31/P2.0/VBLDREF  
P1.7/INT7  
S3C8275X/F8275X  
S3C8278X/F8278X  
S3C8274X/F8274X  
VLC1  
VLC2  
VDD  
VSS  
XOUT  
XIN  
TEST  
XTIN  
9
10  
11  
12  
13  
14  
15  
16  
(64-LQFP-1010)  
XTOUT  
nRESET  
Figure 1-3. S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X Pin Assignments (64-LQFP-1010)  
1-5  
PRODUCT OVERVIEW  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
PIN DESCRIPTIONS  
Table 1-1. S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X Pin Descriptions  
Pin  
Names  
Pin  
Type  
Pin  
Description  
Circuit  
Type  
Pin  
No.  
Shared  
Functions  
I/O  
I/O port with bit-programmable pins;  
Schmitt trigger input or push-pull, open-drain  
output and software assignable pull-ups;  
P0.0P0.2 are alternately used for external  
interrupt input(noise filters, interrupt enable  
and pending control).  
E-4  
P0.0P0.2  
P0.3  
P0.4  
P0.5  
P0.6  
1820  
21  
22  
23  
24  
INT0INT2  
T1CLK  
TAOUT  
TBOUT  
CLKOUT  
BUZ  
P0.7  
25  
P1.0  
P1.1  
P1.2  
P1.3P1.7  
I/O  
I/O port with bit-programmable pins;  
Schmitt trigger input or push-pull, open-drain  
output and software assignable pull-ups;  
P1.3P1.7 are alternately used for external  
interrupt input(noise filters, interrupt enable  
and pending control).  
E-4  
26  
27  
28  
SCK  
SO  
SI  
2933  
INT3INT7  
SEG31/VBLDREF  
P2.0  
P2.1P2.7  
I/O  
I/O  
I/O  
I/O port with bit-programmable pins;  
Input or push-pull, open-drain output and  
software assignable pull-ups.  
H-10  
H-8  
34  
3541  
SEG30SEG24  
I/O port with bit-programmable pins;  
Input or push-pull, open-drain output and  
software assignable pull-ups.  
H-8  
H-9  
P3.0P3.7  
4249  
SEG23SEG16  
I/O port with bit-programmable pins;  
Input or push-pull output and software  
assignable pull-ups.  
P4.0P4.7  
P5.0P5.7  
P6.0P6.3  
5057  
5864, 1  
25  
SEG15SEG8  
SEG7SEG0  
COM0COM3  
1-6  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
PRODUCT OVERVIEW  
Table 1-1. S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X Pin Descriptions (Continued)  
Pin  
Names  
Pin  
Type  
Pin  
Description  
Circuit  
Type  
Pin  
No.  
Shared  
Functions  
LCD power supply pins.  
VLC0VLC2  
68  
I/O  
External interrupts input pins.  
E-4  
INT0INT2  
INT3INT7  
1820  
2933  
P0.0P0.2  
P1.3P1.7  
T1CLK  
I/O  
I/O  
I/O  
I/O  
I/O  
I/O  
I/O  
I/O  
Timer 1/A external clock input.  
Timer 1/A clock output.  
E-4  
E-4  
E-4  
E-4  
E-4  
E-4  
H-9  
21  
22  
23  
24  
25  
P0.3  
P0.4  
P0.5  
P0.6  
P0.7  
TAOUT  
TBOUT  
Timer B clock output.  
CLKOUT  
BUZ  
System clock output.  
Output pin for buzzer signal.  
Serial clock, data output, and data input.  
LCD common signal outputs.  
LCD segment signal outputs.  
SCK, SO, SI  
COM0–COM3  
26,27,28 P1.0, P1.1, P1.2  
25  
P6.0P6.3  
SEG0–SEG15  
SEG16–SEG30  
SEG31  
H-9  
H-8  
H-10  
1,6450  
4935  
34  
P5.7P4.0  
P3.7P2.1  
P2.0/VBLDREF  
VBLDREF  
VREG  
I/O  
O
Battery level detector reference voltage  
H-10  
34  
17  
P2.0/SEG31  
Regulator voltage output for sub clock  
(needed 0.1uF)  
nRESET  
I
System reset pin  
Sub oscillator pins  
B
16  
XTIN, XTOUT  
14, 15  
XIN, XOUT  
TEST  
Main oscillator pins.  
12, 11  
13  
I
Test input: it must be connected to VSS  
Power input pins  
VDD, VSS  
9, 10  
1-7  
PRODUCT OVERVIEW  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
PIN CIRCUITS  
V
DD  
V
DD  
Pull-Up  
Resistor  
P-Channel  
N-Channel  
In  
In  
Schmitt Trigger  
Figure 1-5. Pin Circuit Type B (nRESET)  
Figure 1-4. Pin Circuit Type A  
V
DD  
Pull-up  
Resistor  
V
DD  
Resistor  
Enable  
Open  
Drain  
P-CH  
N-CH  
Data  
I/O  
Output  
Disable  
Schmitt Trigger  
Figure 1-6. Pin Circuit Type E-4 (P0, P1)  
1-8  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
PRODUCT OVERVIEW  
V
V
LC0  
LC1  
COM/SEG  
Out  
Output  
Disable  
V
LC2  
V
SS  
Figure 1-7. Pin Circuit Type H-4  
V
DD  
Pull-Up  
Resistor  
V
DD  
Resistor  
Enable  
Open Drain  
Data  
P-CH  
N-CH  
I/O  
Output  
Disable 1  
SEG  
Circuit  
Type H-4  
Output  
Disable 2  
Figure 1-8. Pin Circuit Type H-8 (P2.1P2.7, P3)  
1-9  
PRODUCT OVERVIEW  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
V
DD  
Pull-Up  
Resistor  
V
DD  
Resistor  
Enable  
P-CH  
N-CH  
Data  
I/O  
Output  
Disable 1  
COM/SEG  
Circuit  
Type H-4  
Output  
Disable 2  
Figure 1-9. Pin Circuit Type H-9 (P4, P5, P6)  
1-10  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
PRODUCT OVERVIEW  
V
DD  
Pull-Up  
Resistor  
V
DD  
Resistor  
Enable  
Open-Drain  
Data  
P-CH  
N-CH  
I/O  
Output  
Disable 1  
SEG  
Circuit  
Type H-4  
Alternative  
Function  
BLDEN  
BLD Select  
To BLD  
Figure 1-10. Pin Circuit Type H-10 (P2.0)  
1-11  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
ADDRESS SPACES  
2
ADDRESS SPACES  
OVERVIEW  
The S3C8275X/C8278X/C8274X microcontroller has two types of address space:  
Internal program memory (ROM)  
Internal register file  
A 16-bit address bus supports program memory operations. A separate 8-bit register bus carries addresses and  
data between the CPU and the register file.  
The S3C8275X has an internal 16-Kbyte mask-programmable ROM. The S3C8278X has an internal 8-Kbyte  
mask-programmable ROM. The S3C8274X has an internal 4-Kbyte mask-programmable ROM.  
The 256-byte physical register space is expanded into an addressable area of 320 bytes using addressing  
modes.  
A 16-byte LCD display register file is implemented.  
There are 605 mapped registers in the internal register file. Of these, 528 are for general-purpose.  
(This number includes a 16-byte working register common area used as a “scratch area” for data operations, two  
192-byte prime register areas, and two 64-byte areas (Set 2)). Thirteen 8-bit registers are used for the CPU and  
the system control, and 48 registers are mapped for peripheral controls and data registers. Nineteen register  
locations are not mapped.  
2-1  
ADDRESS SPACES  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
PROGRAM MEMORY (ROM)  
Program memory (ROM) stores program codes or table data. The S3C8275X has 16K bytes internal mask-  
programmable program memory, the S3C8278X has 8K bytes, the S3C8274X has 4K bytes.  
The first 256 bytes of the ROM (0H–0FFH) are reserved for interrupt vector addresses. Unused locations in this  
address range can be used as normal program memory. If you use the vector address area to store a program  
code, be careful not to overwrite the vector addresses stored in these locations.  
The ROM address at which a program execution starts after a reset is 0100H.  
The reset address of ROM can be changed by a smart option only in the S3F8275X (Full-Flash Device). Refer to  
the chapter 16. Embedded Flash Memory Interface for more detail contents.  
(Decimal)  
16,383  
(HEX)  
3FFFH  
(Decimal)  
8,191  
(HEX)  
1FFFH  
16K-bytes  
Internal  
Program  
Memory  
Area  
(Decimal)  
4,095  
(HEX)  
0FFFH  
8K-bytes  
Internal  
Program  
Memory  
Area  
4K-bytes  
Internal  
Program  
Memory  
Area  
8FFH  
Available  
ISP Sector Area  
255  
255  
255  
FFH  
3FH  
FFH  
3FH  
FFH  
3FH  
Interrupt Vector Area  
Smart Option Area  
Interrupt Vector Area  
Smart Option Area  
Interrupt Vector Area  
Smart Option Area  
3CH  
00H  
3CH  
00H  
3CH  
00H  
0
0
0
S3C8275X/F8275X  
S3C8278X/F8278X  
S3C8274X/F8274X  
Figure 2-1. Program Memory Address Space  
2-2  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
SMART OPTION  
ADDRESS SPACES  
ROM Address: 003EH  
.5 .4 .3 .2  
MSB  
.7  
.6  
.1  
.0  
LSB  
ISP protection size selection: (note)  
00 = 256 bytes  
Not used  
ISP reset vector change enable/disable bit:  
0 = OBP reset vector address  
1 = Normal vector (address 0100H)  
01 = 512 bytes  
10 = 1024 bytes  
11 = 2048 bytes  
ISP reset vector address selection bit:  
00 = 200H (ISP area size: 256 byte)  
01 = 300H (ISP area size: 512 byte)  
10 = 500H (ISP area size: 1024 byte)  
11 = 900H (ISP area size: 2048 byte)  
ISP protection enable/disable bit:  
0 = Enable (not erasable by LDC)  
1 = Disable (erasable by LDC)  
ROM Address: 003FH  
.5 .4 .3 .2  
MSB  
.7  
.6  
.1  
.0  
LSB  
Not used  
LVR enable/disable bit  
(criteria voltage: 2.2V):  
0 = Disable LVR  
These bits should be  
always logic "110b".  
1 = Enable LVR  
ROM Address: 003CH  
.5 .4 .3 .2  
MSB  
.7  
.6  
.1  
.0  
LSB  
Not used  
ROM Address: 003DH  
.5 .4 .3 .2  
MSB  
.7  
.6  
.1  
.0  
LSB  
Not used  
NOTES:  
1. After selecting ISP reset vector address in selecting ISP protection size, don't select upper than ISP  
area size.  
2. When any values are written in the Smart Option area (003CH-003FH) by LDC instruction, the data of  
the area may be changed but the Smart Option is not affected. The data for Smart Option should be  
written in the Smart Option area (003CH-003FH) by OTP/MTP tools (SPW2 plus single  
programmer, or GW-PRO2 gang programmer).  
Figure 2-2. Smart Option  
2-3  
ADDRESS SPACES  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Smart option is the ROM option for start condition of the chip. The ROM address used by smart option is from  
003CH to 003FH.  
The ISP of smart option (003EH) is available in the S3F8275X only. The default value of ROM address 003EH is  
FFH. And ROM address 003EH should be kept FFH when used the  
S3C8275X/C8278X/F8278X/C8274X/F8274X.  
The LVR of smart option (003FH) is available in all the device,  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X. The default value of ROM address 003FH is FFH.  
2-4  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
ADDRESS SPACES  
REGISTER ARCHITECTURE  
In the S3C8275X/C8278X/C8274X implementation, the upper 64-byte area of register files is expanded two  
64-byte areas, called set 1 and set 2. The upper 32-byte area of set 1 is further expanded two 32-byte register  
banks (bank 0 and bank 1), and the lower 32-byte area is a single 32-byte common area.  
In case of S3C8275X the total number of addressable 8-bit registers is 605. Of these 605 registers, 13 bytes are  
for CPU and system control registers, 16 bytes are for LCD data registers, 48 bytes are for peripheral control and  
data registers, 16 bytes are used as a shared working registers, and 512 registers are for general-purpose use,  
page 0-page 1 (in case of S3C8278X/C8274X, page 0).  
You can always address set 1 register locations, regardless of which of the two register pages is currently  
selected. Set 1 locations, however, can only be addressed using register addressing modes.  
The extension of register space into separately addressable areas (sets, banks, and pages) is supported by  
various addressing mode restrictions, the select bank instructions, SB0 and SB1, and the register page pointer  
(PP).  
Specific register types and the area (in bytes) that they occupy in the register file are summarized in Table 2-1.  
Table 2-1. S3C8275X Register Type Summary  
Register Type  
Number of Bytes  
General-purpose registers (including the 16-byte  
common working register area, two 192-byte prime  
register area, and two 64-byte set 2 area)  
LCD data registers  
CPU and system control registers  
Mapped clock, peripheral, I/O control, and data registers  
528  
16  
13  
48  
Total Addressable Bytes  
605  
Table 2-2. S3C8278X/C8274X Register Type Summary  
Register Type  
Number of Bytes  
General-purpose registers (including the 16-byte  
common working register area, one 192-byte prime  
register area, and one 64-byte set 2 area)  
LCD data registers  
CPU and system control registers  
Mapped clock, peripheral, I/O control, and data registers  
272  
16  
13  
48  
Total Addressable Bytes  
349  
2-5  
ADDRESS SPACES  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Set1  
FFH  
FFH  
Bank 1  
Page 1  
Page 0  
FFH  
Bank 0  
32  
Bytes  
System and  
Set 2  
Peripheral Control  
Registers  
General-Purpose  
Data Registers  
E0H  
(Register Addressing Mode)  
E0H  
DFH  
64  
Bytes  
(Indirect Register, Indexed  
Mode, and Stack  
Operations)  
System Registers  
(Register Addressing Mode)  
D0H  
CFH  
256  
Bytes  
C0H  
BFH  
General Purpose Register  
(Register Addressing Mode)  
Page 0  
C0H  
0FH  
Page 2  
~
Prime  
Data Registers  
192  
Bytes  
~
~
Prime  
Data Registers  
(All Addressing Modes)  
16  
Bytes  
~
~
(All addressing modes)  
LCD Display Reigster  
00H  
00H  
Figure 2-3. Internal Register File Organization (S3C8275X)  
2-6  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
ADDRESS SPACES  
Set1  
Bank 1  
FFH  
FFH  
Bank 0  
Page 0  
Set 2  
32  
Bytes  
System and  
Peripheral Control  
Registers  
General-Purpose  
Data Registers  
E0H  
(Register Addressing Mode)  
E0H  
DFH  
64  
Bytes  
(Indirect Register, Indexed  
Mode, and Stack  
Operations)  
System Registers  
(Register Addressing Mode)  
D0H  
CFH  
C0H  
BFH  
General Purpose Register  
(Register Addressing Mode)  
256  
Bytes  
Page 0  
C0H  
0FH  
Page 2  
Prime  
Data Registers  
192  
Bytes  
~
~
Prime  
Data Registers  
(All Addressing Modes)  
16  
Bytes  
~
~
(All addressing modes)  
LCD Display Reigster  
00H  
00H  
NOTE:  
In case of S3C8278X/C8274X, there are page 0 and page 2.  
Page 2 is for LCD display register, 16 bytes.  
Figure 2-4. Internal Register File Organization (S3C8278X/C8274X)  
2-7  
ADDRESS SPACES  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
REGISTER PAGE POINTER (PP)  
The S3C8-series architecture supports the logical expansion of the physical 256-byte internal register file (using  
an 8-bit data bus) into as many as 16 separately addressable register pages. Page addressing is controlled by  
the register page pointer (PP, DFH). In the S3C8275X/C8278X/C8274X microcontroller, a paged register file  
expansion is implemented for LCD data registers, and the register page pointer must be changed to address  
other pages.  
After a reset, the page pointer's source value (lower nibble) and the destination value (upper nibble) are always  
"0000", automatically selecting page 0 as the source and destination page for register addressing.  
Register Page Pointer (PP)  
DFH, Set 1, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
Source register page selection bits:  
0000 Source: Page 0  
0001 Source: Page 1 (Not used for the S3C8278X/C8274X)  
0010 Source: Page 2  
others Not used for the S3C8275X/C8278X/C8274X  
Destination register page selection bits:  
0000 Destination: Page 0  
0001 Destination: Page 1 (Not used for the S3C8278X/C8274X)  
0010 Destination: Page 2  
others Not used for the S3C8275X/C8278X/C8274X  
NOTES:  
1. In the S3C8275X microcontroller, the internal register file is configured as three pages (Pages 0-2).  
The pages 0-1 are used for general purpose register file, and page 2 is used for LCD data register or  
general purpose register.  
2. In the S3C8278X/C8274X microcontroller, the internal register file is configured as two pages (Pages 0, 2).  
The page 0 is used for general purpose register file, and page 2 is used for LCD data register or general  
purpose register.  
3. A hardware reset operation writes the 4-bit destination and source values shown above to the register page  
pointer. These values should be modified to address other pages.  
Figure 2-5. Register Page Pointer (PP)  
2-8  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
ADDRESS SPACES  
PROGRAMMING TIP — Using the Page Pointer for RAM Clear (Page 0, Page 1)  
LD  
PP,#00H  
#0C0H  
; Destination 0, Source 0  
SRP  
LD  
R0,#0FFH  
@R0  
R0,RAMCL0  
@R0  
; Page 0 RAM clear starts  
; R0 = 00H  
RAMCL0  
RAMCL1  
CLR  
DJNZ  
CLR  
LD  
PP,#10H  
; Destination 1, Source 0  
LD  
R0,#0FFH  
@R0  
R0,RAMCL1  
@R0  
; Page 1 RAM clear starts  
CLR  
DJNZ  
CLR  
; R0 = 00H  
NOTE: You should refer to page 6-39 and use DJNZ instruction properly when DJNZ instruction is used in your program.  
2-9  
ADDRESS SPACES  
REGISTER SET 1  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
The term set 1 refers to the upper 64 bytes of the register file, locations C0H–FFH.  
The upper 32-byte area of this 64-byte space (E0H–FFH) is expanded two 32-byte register banks, bank 0 and  
bank 1. The set register bank instructions, SB0 or SB1, are used to address one bank or the other. A hardware  
reset operation always selects bank 0 addressing.  
The upper two 32-byte areas (bank 0 and bank 1) of set 1 (E0H–FFH) contains 48 mapped system and  
peripheral control registers. The lower 32-byte area contains 16 system registers (D0H–DFH) and a 16-byte  
common working register area (C0H–CFH). You can use the common working register area as a “scratch” area  
for data operations being performed in other areas of the register file.  
Registers in set 1 locations are directly accessible at all times using Register addressing mode. The 16-byte  
working register area can only be accessed using working register addressing (For more information about  
working register addressing, please refer to Chapter 3, “Addressing Modes.”)  
REGISTER SET 2  
The same 64-byte physical space that is used for set 1 locations C0H–FFH is logically duplicated to add another  
64 bytes of register space. This expanded area of the register file is called set 2. For the S3C8275X,  
the set 2 address range (C0H–FFH) is accessible on pages 0–1.  
S3C8278X/C8274X, the set 2 address range (C0H–FFH) is accessible on page 0.  
The logical division of set 1 and set 2 is maintained by means of addressing mode restrictions. You can use only  
Register addressing mode to access set 1 locations. In order to access registers in set 2, you must use Register  
Indirect addressing mode or Indexed addressing mode.  
The set 2 register area is commonly used for stack operations.  
2-10  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
PRIME REGISTER SPACE  
ADDRESS SPACES  
The lower 192 bytes (00H–BFH) of the S3C8275X/C8278X/C8274X's two or one 256-byte register pages is  
called prime register area. Prime registers can be accessed using any of the seven addressing modes  
(see Chapter 3, "Addressing Modes.")  
The prime register area on page 0 is immediately addressable following a reset. In order to address prime  
registers on pages 0, 1, or 2 you must set the register page pointer (PP) to the appropriate source and destination  
values.  
FFH  
FFH  
Set 1  
Page 1  
Bank 0  
Bank 1  
Page 0  
Set 2  
FFH  
FCH  
E0H  
D0H  
C0H  
C0H  
BFH  
Page 0  
Prime  
Space  
CPU and system control  
General-purpose  
Page 2  
0FH  
00H  
LCD Data  
Register Area  
Peripheral and I/O  
LCD data register  
00H  
NOTE:  
In case of S3C8278X/C8274X, there are page 0 and page 2. Page 2 is for LCD display  
register, 16 bytes.  
Figure 2-6. Set 1, Set 2, Prime Area Register, and LCD Data Register Map  
2-11  
ADDRESS SPACES  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
WORKING REGISTERS  
Instructions can access specific 8-bit registers or 16-bit register pairs using either 4-bit or 8-bit address fields.  
When 4-bit working register addressing is used, the 256-byte register file can be seen by the programmer as one  
that consists of 32 8-byte register groups or "slices." Each slice comprises of eight 8-bit registers.  
Using the two 8-bit register pointers, RP1 and RP0, two working register slices can be selected at any one time to  
form a 16-byte working register block. Using the register pointers, you can move this 16-byte register block  
anywhere in the addressable register file, except the set 2 area.  
The terms slice and block are used in this manual to help you visualize the size and relative locations of selected  
working register spaces:  
— One working register slice is 8 bytes (eight 8-bit working registers, R0–R7 or R8–R15)  
— One working register block is 16 bytes (sixteen 8-bit working registers, R0–R15)  
All the registers in an 8-byte working register slice have the same binary value for their five most significant  
address bits. This makes it possible for each register pointer to point to one of the 24 slices in the register file.  
The base addresses for the two selected 8-byte register slices are contained in register pointers RP0 and RP1.  
After a reset, RP0 and RP1 always point to the 16-byte common area in set 1 (C0H–CFH).  
FFH  
Slice 32  
F8H  
F7H  
F0H  
Slice 31  
1 1 1 1 1 X X X  
Set 1  
Only  
RP1 (Registers R8-R15)  
Each register pointer points to  
one 8-byte slice of the register  
space, selecting a total 16-byte  
working register block.  
CFH  
C0H  
~
~
0 0 0 0 0 X X X  
10H  
FH  
8H  
7H  
0H  
RP0 (Registers R0-R7)  
Slice 2  
Slice 1  
Figure 2-7. 8-Byte Working Register Areas (Slices)  
2-12  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
USING THE REGISTER POINTS  
ADDRESS SPACES  
Register pointers RP0 and RP1, mapped to addresses D6H and D7H in set 1, are used to select two movable  
8-byte working register slices in the register file. After a reset, they point to the working register common area:  
RP0 points to addresses C0H–C7H, and RP1 points to addresses C8H–CFH.  
To change a register pointer value, you load a new value to RP0 and/or RP1 using an SRP or LD instruction.  
(see Figures 2-8 and 2-9).  
With working register addressing, you can only access those two 8-bit slices of the register file that are currently  
pointed to by RP0 and RP1. You cannot, however, use the register pointers to select a working register space in  
set 2, C0H–FFH, because these locations can be accessed only using the Indirect Register or Indexed  
addressing modes.  
The selected 16-byte working register block usually consists of two contiguous 8-byte slices. As a general  
programming guideline, it is recommended that RP0 point to the "lower" slice and RP1 point to the "upper" slice  
(see Figure 2-8). In some cases, it may be necessary to define working register areas in different (non-  
contiguous) areas of the register file. In Figure 2-9, RP0 points to the "upper" slice and RP1 to the "lower" slice.  
Because a register pointer can point to either of the two 8-byte slices in the working register block, you can  
flexibly define the working register area to support program requirements.  
PROGRAMMING TIP — Setting the Register Pointers  
SRP  
SRP1  
SRP0  
CLR  
LD  
#70H  
#48H  
#0A0H  
RP0  
RP1,#0F8H  
; RP0 70H, RP1 78H  
; RP0 no change, RP1 48H,  
; RP0 A0H, RP1 no change  
; RP0 00H, RP1 no change  
; RP0 no change, RP1 0F8H  
Register File  
Contains 32  
8-Byte Slices  
0 0 0 0 1 X X X  
RP1  
FH (R15)  
16-Byte  
Contiguous  
Working  
8-Byte Slice  
8-Byte Slice  
8H  
7H  
0 0 0 0 0 X X X  
RP0  
Register block  
0H (R0)  
Figure 2-8. Contiguous 16-Byte Working Register Block  
2-13  
ADDRESS SPACES  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
F7H (R7)  
8-Byte Slice  
F0H (R0)  
16-Byte  
Contiguous  
working  
Register File  
Contains 32  
8-Byte Slices  
1 1 1 1 0 X X X  
Register block  
RP0  
0 0 0 0 0 X X X  
RP1  
7H (R15)  
0H (R0)  
8-Byte Slice  
Figure 2-9. Non-Contiguous 16-Byte Working Register Block  
PROGRAMMING TIP — Using the RPs to Calculate the Sum of a Series of Registers  
Calculate the sum of registers 80H–85H using the register pointer. The register addresses from 80H through 85H  
contain the values 10H, 11H, 12H, 13H, 14H, and 15H respectively:  
SRP0  
ADD  
ADC  
ADC  
ADC  
ADC  
#80H  
; RP0 80H  
R0,R1  
R0,R2  
R0,R3  
R0,R4  
R0,R5  
; R0 R0 + R1  
; R0 R0 + R2 + C  
; R0 R0 + R3 + C  
; R0 R0 + R4 + C  
; R0 R0 + R5 + C  
The sum of these six registers, 6FH, is located in the register R0 (80H). The instruction string used in this  
example takes 12 bytes of instruction code and its execution time is 36 cycles. If the register pointer is not used to  
calculate the sum of these registers, the following instruction sequence would have to be used:  
ADD  
ADC  
ADC  
ADC  
ADC  
80H,81H  
80H,82H  
80H,83H  
80H,84H  
80H,85H  
; 80H (80H) + (81H)  
; 80H (80H) + (82H) + C  
; 80H (80H) + (83H) + C  
; 80H (80H) + (84H) + C  
; 80H (80H) + (85H) + C  
Now, the sum of the six registers is also located in register 80H. However, this instruction string takes 15 bytes of  
instruction code rather than 12 bytes, and its execution time is 50 cycles rather than 36 cycles.  
2-14  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
ADDRESS SPACES  
REGISTER ADDRESSING  
The S3C8-series register architecture provides an efficient method of working register addressing that takes full  
advantage of shorter instruction formats to reduce execution time.  
With Register (R) addressing mode, in which the operand value is the content of a specific register or register  
pair, you can access any location in the register file except for set 2. With working register addressing, you use a  
register pointer to specify an 8-byte working register space in the register file and an 8-bit register within that  
space.  
Registers are addressed either as a single 8-bit register or as a paired 16-bit register space. In a 16-bit register  
pair, the address of the first 8-bit register is always an even number and the address of the next register is always  
an odd number. The most significant byte of the 16-bit data is always stored in the even-numbered register, and  
the least significant byte is always stored in the next (+1) odd-numbered register.  
Working register addressing differs from Register addressing as it uses a register pointer to identify a specific  
8-byte working register space in the internal register file and a specific 8-bit register within that space.  
MSB  
Rn  
LSB  
n = Even address  
Rn+1  
Figure 2-10. 16-Bit Register Pair  
2-15  
ADDRESS SPACES  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Special-Purpose Registers  
General-Purpose Register  
Bank 1  
Bank 0  
FFH  
FFH  
Control  
Registers  
E0H  
D0H  
Set 2  
System  
Registers  
CFH  
C0H  
C0H  
BFH  
RP1  
RP0  
Register  
Pointers  
Each register pointer (RP) can independently point  
to one of the 24 8-byte "slices" of the register file  
(other than set 2). After a reset, RP0 points to  
locations C0H-C7H and RP1 to locations C8H-CFH  
(that is, to the common working register area).  
Prime  
Registers  
LCD Data  
Registers  
NOTE:  
In the S3C8275X/C8278X/C8274X microcontroller,  
pages 0-2 are implemented.  
Pages 0-2 contain all of the addressable  
registers in the internal register file.  
00H  
Page 0  
Page 0  
Register Addressing Only  
All  
Indirect Register,  
Indexed  
All  
Addressing  
Modes  
Addressing  
Modes  
Addressing  
Modes  
Can be Pointed by Register Pointer  
Can be Pointed to  
By register Pointer  
Figure 2-11. Register File Addressing  
2-16  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
ADDRESS SPACES  
COMMON WORKING REGISTER AREA (C0H–CFH)  
After a reset, register pointers RP0 and RP1 automatically select two 8-byte register slices in set 1, locations  
C0H–CFH, as the active 16-byte working register block:  
RP0 C0H–C7H  
RP1 C8H–CFH  
This 16-byte address range is called common area. That is, locations in this area can be used as working  
registers by operations that address any location on any page in the register file. Typically, these working  
registers serve as temporary buffers for data operations between different pages.  
FFH  
Page 1  
Set 1  
FFH  
Page 0  
FFH  
FCH  
Set 2  
E0H  
D0H  
C0H  
C0H  
BFH  
Page 0  
Following a hardware reset, register  
pointers RP0 and RP1 point to the  
common working register area,  
locations C0H-CFH.  
~
Prime  
Space  
~
~
Page 2  
0FH  
00H  
LCD Data  
Registers  
RP0 = 1 1 0 0  
RP1 = 1 1 0 0  
0 0 0 0  
1 0 0 0  
00H  
NOTE:  
In case of S3C8278X/C8274X, there are page 0 and page 2.  
Page 2 is for LCD display register, 16 bytes.  
Figure 2-12. Common Working Register Area  
2-17  
ADDRESS SPACES  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
PROGRAMMING TIP — Addressing the Common Working Register Area  
As the following examples show, you should access working registers in the common area, locations C0H–CFH,  
using working register addressing mode only.  
Examples 1. LD  
0C2H,40H  
; Invalid addressing mode!  
Use working register addressing instead:  
SRP  
LD  
#0C0H  
R2,40H  
; R2 (C2H) the value in location 40H  
2. ADD  
0C3H,#45H  
; Invalid addressing mode!  
Use working register addressing instead:  
SRP  
#0C0H  
ADD  
R3,#45H  
; R3 (C3H) R3 + 45H  
4-BIT WORKING REGISTER ADDRESSING  
Each register pointer defines a movable 8-byte slice of working register space. The address information stored in  
a register pointer serves as an addressing "window" that makes it possible for instructions to access working  
registers very efficiently using short 4-bit addresses. When an instruction addresses a location in the selected  
working register area, the address bits are concatenated in the following way to form a complete 8-bit address:  
— The high-order bit of the 4-bit address selects one of the register pointers ("0" selects RP0, "1" selects RP1).  
— The five high-order bits in the register pointer select an 8-byte slice of the register space.  
— The three low-order bits of the 4-bit address select one of the eight registers in the slice.  
As shown in Figure 2-13, the result of this operation is that the five high-order bits from the register pointer are  
concatenated with the three low-order bits from the instruction address to form the complete address. As long as  
the address stored in the register pointer remains unchanged, the three bits from the address will always point to  
an address in the same 8-byte register slice.  
Figure 2-14 shows a typical example of 4-bit working register addressing. The high-order bit of the instruction  
"INC R6" is "0", which selects RP0. The five high-order bits stored in RP0 (01110B) are concatenated with the  
three low-order bits of the instruction's 4-bit address (110B) to produce the register address 76H (01110110B).  
2-18  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
ADDRESS SPACES  
RP0  
RP1  
Selects  
RP0 or RP1  
Address  
OPCODE  
4-bit address  
provides three  
low-order bits  
Register pointer  
provides five  
high-order bits  
Together they create an  
8-bit register address  
Figure 2-13. 4-Bit Working Register Addressing  
RP0  
0 1 1 1 0  
RP1  
0 1 1 1 1  
0 0 0  
0 0 0  
Selects RP0  
R6  
OPCODE  
1 1 1 0  
Register  
address  
(76H)  
Instruction  
'INC R6'  
0 1 1 1 0  
1 1 0  
0 1 1 0  
Figure 2-14. 4-Bit Working Register Addressing Example  
2-19  
ADDRESS SPACES  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
8-BIT WORKING REGISTER ADDRESSING  
You can also use 8-bit working register addressing to access registers in a selected working register area. To  
initiate 8-bit working register addressing, the upper four bits of the instruction address must contain the value  
"1100B." This 4-bit value (1100B) indicates that the remaining four bits have the same effect as 4-bit working  
register addressing.  
As shown in Figure 2-15, the lower nibble of the 8-bit address is concatenated in much the same way as for 4-bit  
addressing: Bit 3 selects either RP0 or RP1, which then supplies the five high-order bits of the final address; the  
three low-order bits of the complete address are provided by the original instruction.  
Figure 2-16 shows an example of 8-bit working register addressing. The four high-order bits of the instruction  
address (1100B) specify 8-bit working register addressing. Bit 4 ("1") selects RP1 and the five high-order bits in  
RP1 (10101B) become the five high-order bits of the register address. The three low-order bits of the register  
address (011) are provided by the three low-order bits of the 8-bit instruction address. The five address bits from  
RP1 and the three address bits from the instruction are concatenated to form the complete register address,  
0ABH (10101011B).  
RP0  
RP1  
Selects  
RP0 or RP1  
Address  
These address  
bits indicate 8-bit  
working register  
addressing  
8-bit logical  
address  
1
1
0
0
Register pointer  
provides five  
Three low-order bits  
high-order bits  
8-bit physical address  
Figure 2-15. 8-Bit Working Register Addressing  
2-20  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
ADDRESS SPACES  
RP0  
RP1  
1 0 1 0 1  
0 1 1 0 0  
0 0 0  
0 0 0  
Selects RP1  
R11  
8-bit address  
form instruction  
'LD R11, R2'  
Register  
address  
(0ABH)  
1 1 0 0  
1
0 1 1  
1 0 1 0 1  
0 1 1  
Specifies working  
register addressing  
Figure 2-16. 8-Bit Working Register Addressing Example  
2-21  
ADDRESS SPACES  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
SYSTEM AND USER STACK  
The S3C8-series microcontrollers use the system stack for data storage, subroutine calls and returns. The PUSH  
and POP instructions are used to control system stack operations. The S3C8275X/C8278X/C8274X architecture  
supports stack operations in the internal register file.  
Stack Operations  
Return addresses for procedure calls, interrupts, and data are stored on the stack. The contents of the PC are  
saved to stack by a CALL instruction and restored by the RET instruction. When an interrupt occurs, the contents  
of the PC and the FLAGS register are pushed to the stack. The IRET instruction then pops these values back to  
their original locations. The stack address value is always decreased by one before a push operation and  
increased by one after a pop operation. The stack pointer (SP) always points to the stack frame stored on the top  
of the stack, as shown in Figure 2-17.  
High Address  
PCL  
PCL  
PCH  
Top of  
PCH  
stack  
Top of  
stack  
Flags  
Stack contents  
after a call  
Stack contents  
after an  
instruction  
interrupt  
Low Address  
Figure 2-17. Stack Operations  
User-Defined Stacks  
You can freely define stacks in the internal register file as data storage locations. The instructions PUSHUI,  
PUSHUD, POPUI, and POPUD support user-defined stack operations.  
Stack Pointers (SPL, SPH)  
Register locations D8H and D9H contain the 16-bit stack pointer (SP) that is used for system stack operations.  
The most significant byte of the SP address, SP15–SP8, is stored in the SPH register (D8H), and the least  
significant byte, SP7–SP0, is stored in the SPL register (D9H). After a reset, the SP value is undetermined.  
Because only internal memory space is implemented in the S3C8275X/C8278X/C8274X, the SPL must be  
initialized to an 8-bit value in the range 00H–FFH. The SPH register is not needed and can be used as a general-  
purpose register, if necessary.  
When the SPL register contains the only stack pointer value (that is, when it points to a system stack in the  
register file), you can use the SPH register as a general-purpose data register. However, if an overflow or  
underflow condition occurs as a result of increasing or decreasing the stack address value in the SPL register  
during normal stack operations, the value in the SPL register will overflow (or underflow) to the SPH register,  
overwriting any other data that is currently stored there. To avoid overwriting data in the SPH register, you can  
initialize the SPL value to "FFH" instead of "00H".  
2-22  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
ADDRESS SPACES  
Programming TIP — Standard Stack Operations Using PUSH and POP  
The following example shows you how to perform stack operations in the internal register file using PUSH and  
POP instructions:  
LD  
SPL,#0FFH  
; SPL FFH  
; (Normally, the SPL is set to 0FFH by the initialization  
; routine)  
PUSH  
PUSH  
PUSH  
PP  
; Stack address 0FEH PP  
; Stack address 0FDH RP0  
; Stack address 0FCH RP1  
; Stack address 0FBH R3  
RP0  
RP1  
R3  
PUSH  
POP  
POP  
POP  
POP  
R3  
; R3 Stack address 0FBH  
; RP1 Stack address 0FCH  
; RP0 Stack address 0FDH  
; PP Stack address 0FEH  
RP1  
RP0  
PP  
2-23  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
ADDRESSING MODES  
3
ADDRESSING MODES  
OVERVIEW  
Instructions that are stored in program memory are fetched for execution using the program counter. Instructions  
indicate the operation to be performed and the data to be operated on. Addressing mode is the method used to  
determine the location of the data operand. The operands specified in SAM88RC instructions may be condition  
codes, immediate data, or a location in the register file, program memory, or data memory.  
The S3C8-series instruction set supports seven explicit addressing modes. Not all of these addressing modes are  
available for each instruction. The seven addressing modes and their symbols are:  
Register (R)  
Indirect Register (IR)  
Indexed (X)  
Direct Address (DA)  
Indirect Address (IA)  
Relative Address (RA)  
Immediate (IM)  
3-1  
ADDRESSING MODES  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
REGISTER ADDRESSING MODE (R)  
In Register addressing mode (R), the operand value is the content of a specified register or register pair  
(see Figure 3-1).  
Working register addressing differs from Register addressing in that it uses a register pointer to specify an 8-byte  
working register space in the register file and an 8-bit register within that space (see Figure 3-2).  
Program Memory  
Register File  
OPERAND  
8-bit Register  
File Address  
dst  
Point to One  
Register in Register  
File  
OPCODE  
One-Operand  
Instruction  
Value used in  
Instruction Execution  
(Example)  
Sample Instruction:  
DEC  
CNTR  
;
Where CNTR is the label of an 8-bit register address  
Figure 3-1. Register Addressing  
Register File  
MSB Point to  
RP0 ot RP1  
RP0 or RP1  
Selected  
RP points  
to start  
Program Memory  
of working  
register  
block  
4-bit  
Working Register  
3 LSBs  
dst  
src  
Point to the  
Working Register  
(1 of 8)  
OPCODE  
OPERAND  
Two-Operand  
Instruction  
(Example)  
Sample Instruction:  
ADD R1, R2  
;
Where R1 and R2 are registers in the currently  
selected working register area.  
Figure 3-2. Working Register Addressing  
3-2  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
ADDRESSING MODES  
INDIRECT REGISTER ADDRESSING MODE (IR)  
In Indirect Register (IR) addressing mode, the content of the specified register or register pair is the address of the  
operand. Depending on the instruction used, the actual address may point to a register in the register file, to  
program memory (ROM), or to an external memory space (see Figures 3-3 through 3-6).  
You can use any 8-bit register to indirectly address another register. Any 16-bit register pair can be used to  
indirectly address another memory location. Please note, however, that you cannot access locations C0H–FFH in  
set 1 using the Indirect Register addressing mode.  
Program Memory  
Register File  
ADDRESS  
8-bit Register  
File Address  
dst  
Point to One  
Register in Register  
File  
OPCODE  
One-Operand  
Instruction  
Address of Operand  
used by Instruction  
(Example)  
OPERAND  
Value used in  
Instruction Execution  
Sample Instruction:  
RL  
@SHIFT  
;
Where SHIFT is the label of an 8-bit register address  
Figure 3-3. Indirect Register Addressing to Register File  
3-3  
ADDRESSING MODES  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INDIRECT REGISTER ADDRESSING MODE (Continued)  
Register File  
Program Memory  
Example  
REGISTER  
PAIR  
dst  
Instruction  
References  
Program  
Points to  
Register Pair  
OPCODE  
16-Bit  
Memory  
Address  
Points to  
Program  
Memory  
Program Memory  
OPERAND  
Sample Instructions:  
Value used in  
Instruction  
CALL  
JP  
@RR2  
@RR2  
Figure 3-4. Indirect Register Addressing to Program Memory  
3-4  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
ADDRESSING MODES  
INDIRECT REGISTER ADDRESSING MODE (Continued)  
Register File  
MSB Points to  
RP0 or RP1  
RP0 or RP1  
Selected  
RP points  
to start fo  
working register  
block  
Program Memory  
~
~
~
~
4-bit  
Working  
Register  
Address  
3 LSBs  
dst  
src  
Point to the  
Working Register  
(1 of 8)  
ADDRESS  
OPERAND  
OPCODE  
Sample Instruction:  
OR R3, @R6  
Value used in  
Instruction  
Figure 3-5. Indirect Working Register Addressing to Register File  
3-5  
ADDRESSING MODES  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INDIRECT REGISTER ADDRESSING MODE (Concluded)  
Register File  
RP0 or RP1  
MSB Points to  
RP0 or RP1  
Selected  
RP points  
to start of  
working  
register  
block  
Program Memory  
4-bit Working  
Register Address  
dst  
src  
Register  
Pair  
Next 2-bit Point  
to Working  
Register Pair  
(1 of 4)  
OPCODE  
Example Instruction  
References either  
Program Memory or  
Data Memory  
16-Bit  
address  
points to  
program  
memory  
or data  
Program Memory  
or  
Data Memory  
LSB Selects  
memory  
Value used in  
Instruction  
OPERAND  
Sample Instructions:  
LCD  
LDE  
LDE  
R5,@RR6  
R3,@RR14  
@RR4, R8  
; Program memory access  
; External data memory access  
; External data memory access  
Figure 3-6. Indirect Working Register Addressing to Program or Data Memory  
3-6  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
ADDRESSING MODES  
INDEXED ADDRESSING MODE (X)  
Indexed (X) addressing mode adds an offset value to a base address during instruction execution in order to  
calculate the effective operand address (see Figure 3-7). You can use Indexed addressing mode to access  
locations in the internal register file or in external memory. Please note, however, that you cannot access  
locations C0H–FFH in set 1 using Indexed addressing mode.  
In short offset Indexed addressing mode, the 8-bit displacement is treated as a signed integer in the range –128  
to +127. This applies to external memory accesses only (see Figure 3-8.)  
For register file addressing, an 8-bit base address provided by the instruction is added to an 8-bit offset contained  
in a working register. For external memory accesses, the base address is stored in the working register pair  
designated in the instruction. The 8-bit or 16-bit offset given in the instruction is then added to that base address  
(see Figure 3-9).  
The only instruction that supports Indexed addressing mode for the internal register file is the Load instruction  
(LD). The LDC and LDE instructions support Indexed addressing mode for internal program memory and for  
external data memory, when implemented.  
Register File  
RP0 or RP1  
~
~
~
~
Selected RP  
points to  
start of  
working  
register  
block  
Value used in  
Instruction  
OPERAND  
+
Program Memory  
Base Address  
3 LSBs  
Two-Operand  
Instruction  
Example  
dst/src  
x
INDEX  
Point to One of the  
Woking Register  
(1 of 8)  
OPCODE  
Sample Instruction:  
LD R0, #BASE[R1]  
;
Where BASE is an 8-bit immediate value  
Figure 3-7. Indexed Addressing to Register File  
3-7  
ADDRESSING MODES  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INDEXED ADDRESSING MODE (Continued)  
Register File  
RP0 or RP1  
MSB Points to  
RP0 or RP1  
Selected  
RP points  
to start of  
working  
register  
block  
~
~
Program Memory  
OFFSET  
NEXT 2 Bits  
4-bit Working  
Register Address  
dst/src  
x
Register  
Pair  
Point to Working  
Register Pair  
(1 of 4)  
OPCODE  
16-Bit  
address  
added to  
offset  
Program Memory  
or  
LSB Selects  
Data Memory  
+
16-Bits  
8-Bits  
Value used in  
Instruction  
OPERAND  
16-Bits  
Sample Instructions:  
LDC  
LDE  
R4, #04H[RR2]  
R4,#04H[RR2]  
;
;
The values in the program address (RR2 + 04H)  
are loaded into register R4.  
Identical operation to LDC example, except that  
external program memory is accessed.  
Figure 3-8. Indexed Addressing to Program or Data Memory with Short Offset  
3-8  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
ADDRESSING MODES  
INDEXED ADDRESSING MODE (Concluded)  
Register File  
RP0 or RP1  
MSB Points to  
RP0 or RP1  
Selected  
RP points  
to start of  
working  
register  
block  
Program Memory  
~
~
OFFSET  
OFFSET  
NEXT 2 Bits  
4-bit Working  
Register Address  
dst/src  
src  
Register  
Pair  
Point to Working  
Register Pair  
OPCODE  
16-Bit  
address  
added to  
offset  
Program Memory  
or  
LSB Selects  
Data Memory  
+
16-Bits  
8-Bits  
Value used in  
Instruction  
OPERAND  
16-Bits  
Sample Instructions:  
LDC  
LDE  
R4, #1000H[RR2]  
R4,#1000H[RR2]  
; The values in the program address (RR2 + 1000H)  
are loaded into register R4.  
; Identical operation to LDC example, except that  
external program memory is accessed.  
Figure 3-9. Indexed Addressing to Program or Data Memory  
3-9  
ADDRESSING MODES  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
DIRECT ADDRESS MODE (DA)  
In Direct Address (DA) mode, the instruction provides the operand's 16-bit memory address. Jump (JP) and Call  
(CALL) instructions use this addressing mode to specify the 16-bit destination address that is loaded into the PC  
whenever a JP or CALL instruction is executed.  
The LDC and LDE instructions can use Direct Address mode to specify the source or destination address for  
Load operations to program memory (LDC) or to external data memory (LDE), if implemented.  
Program or  
Data Memory  
Memory  
Address  
Used  
Program Memory  
Upper Address Byte  
Lower Address Byte  
dst/src "0" or "1"  
OPCODE  
LSB Selects Program  
Memory or Data Memory:  
"0" = Program Memory  
"1" = Data Memory  
Sample Instructions:  
LDC  
LDE  
R5,1234H  
R5,1234H  
;
;
The values in the program address (1234H)  
are loaded into register R5.  
Identical operation to LDC example, except that  
external program memory is accessed.  
Figure 3-10. Direct Addressing for Load Instructions  
3-10  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
ADDRESSING MODES  
DIRECT ADDRESS MODE (Continued)  
Program Memory  
Next OPCODE  
Memory  
Address  
Used  
Upper Address Byte  
Lower Address Byte  
OPCODE  
Sample Instructions:  
JP  
C,JOB1  
;
;
Where JOB1 is a 16-bit immediate address  
Where DISPLAY is a 16-bit immediate address  
CALL DISPLAY  
Figure 3-11. Direct Addressing for Call and Jump Instructions  
3-11  
ADDRESSING MODES  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INDIRECT ADDRESS MODE (IA)  
In Indirect Address (IA) mode, the instruction specifies an address located in the lowest 256 bytes of the program  
memory. The selected pair of memory locations contains the actual address of the next instruction to be executed.  
Only the CALL instruction can use the Indirect Address mode.  
Because the Indirect Address mode assumes that the operand is located in the lowest 256 bytes of program  
memory, only an 8-bit address is supplied in the instruction; the upper bytes of the destination address are  
assumed to be all zeros.  
Program Memory  
Next Instruction  
LSB Must be Zero  
dst  
Current  
OPCODE  
Instruction  
Lower Address Byte  
Upper Address Byte  
Program Memory  
Locations 0-255  
Sample Instruction:  
CALL #40H  
; The 16-bit value in program memory addresses 40H  
and 41H is the subroutine start address.  
Figure 3-12. Indirect Addressing  
3-12  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
ADDRESSING MODES  
RELATIVE ADDRESS MODE (RA)  
In Relative Address (RA) mode, a twos-complement signed displacement between – 128 and + 127 is specified  
in the instruction. The displacement value is then added to the current PC value. The result is the address of the  
next instruction to be executed. Before this addition occurs, the PC contains the address of the instruction  
immediately following the current instruction.  
Several program control instructions use the Relative Address mode to perform conditional jumps. The  
instructions that support RA addressing are BTJRF, BTJRT, DJNZ, CPIJE, CPIJNE, and JR.  
Program Memory  
Next OPCODE  
Program Memory  
Address Used  
Current  
PC Value  
+
Displacement  
OPCODE  
Current Instruction  
Signed  
Displacement Value  
Sample Instructions:  
JR  
ULT,$+OFFSET  
;
Where OFFSET is a value in the range +127 to -128  
Figure 3-13. Relative Addressing  
3-13  
ADDRESSING MODES  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
IMMEDIATE MODE (IM)  
In Immediate (IM) addressing mode, the operand value used in the instruction is the value supplied in the operand  
field itself. The operand may be one byte or one word in length, depending on the instruction used. Immediate  
addressing mode is useful for loading constant values into registers.  
Program Memory  
OPERAND  
OPCODE  
(The Operand value is in the instruction)  
Sample Instruction:  
LD  
R0,#0AAH  
Figure 3-14. Immediate Addressing  
3-14  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CONTROL REGISTER  
4
CONTROL REGISTERS  
OVERVIEW  
In this chapter, detailed descriptions of the S3C8275X/C8278X/C8274X control registers are presented in an  
easy-to-read format. You can use this chapter as a quick-reference source when writing application programs.  
Figure 4-1 illustrates the important features of the standard register description format.  
Control register descriptions are arranged in alphabetical order according to register mnemonic. More detailed  
information about control registers is presented in the context of the specific peripheral hardware descriptions in  
Part II of this manual.  
Data and counter registers are not described in detail in this reference chapter. More information about all of the  
registers used by a specific peripheral is presented in the corresponding peripheral descriptions in Part II of this  
manual.  
The locations and read/write characteristics of all mapped registers in the S3C8275X/C8278X/C8274X register  
file are listed in Table 4-1. The hardware reset value for each mapped register is described in Chapter 8, "RESET  
and Power-Down."  
Table 4-1. Set 1 Registers  
Register Name  
Mnemonic  
Address  
Decimal  
Locations D0H – D2H are not mapped.  
R/W  
Hex  
Basic timer control register  
System clock control register  
System flags register  
BTCON  
CLKCON  
FLAGS  
RP0  
211  
212  
213  
214  
215  
216  
217  
218  
219  
220  
221  
222  
223  
D3H  
D4H  
D5H  
D6H  
D7H  
D8H  
D9H  
DAH  
DBH  
DCH  
DDH  
DEH  
DFH  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R
Register pointer 0  
Register pointer 1  
RP1  
Stack pointer (high byte)  
Stack pointer (low byte)  
Instruction pointer (high byte)  
Instruction pointer (low byte)  
Interrupt request register  
Interrupt mask register  
System mode register  
Register page pointer  
SPH  
SPL  
IPH  
IPL  
IRQ  
IMR  
R/W  
R/W  
R/W  
SYM  
PP  
4-1  
CONTROL REGISTERS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Table 4-2. Set 1, Bank 0 Registers  
Register Name  
Mnemonic  
Address  
Decimal  
R/W  
Hex  
E0H  
E1H  
E2H  
E3H  
E4H  
E5H  
E6H  
E7H  
E8H  
E9H  
EAH  
EBH  
ECH  
EDH  
EEH  
EFH  
F0H  
F1H  
F2H  
F3H  
F4H  
F5H  
F6H  
F7H  
F8H  
F9H  
Oscillator control register  
OSCCON  
SIOCON  
SIODATA  
SIOPS  
P0CONH  
P0CONL  
P0PUR  
P1CONH  
P1CONL  
P1PUR  
P2CONH  
P2CONL  
P2PUR  
P3CONH  
P3CONL  
P3PUR  
P0  
224  
225  
226  
227  
228  
229  
230  
231  
232  
233  
234  
235  
236  
237  
238  
239  
240  
241  
242  
243  
244  
245  
246  
247  
248  
249  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
SIO control register  
SIO data register  
SIO pre-scaler register  
Port 0 control register (high byte)  
Port 0 control register (low byte)  
Port 0 pull-up resistor enable register  
Port 1 control register (high byte)  
Port 1 control register (low byte)  
Port 1 pull-up resistor enable register  
Port 2 control register (high byte)  
Port 2 control register (low byte)  
Port 2 pull-up resistor enable register  
Port 3 control register (high byte)  
Port 3 control register (low byte)  
Port 3 Pull-up resistor enable register  
Port 0 data register  
Port 1 data register  
P1  
Port 2 data register  
P2  
Port 3 data register  
P3  
Port 4 data register  
P4  
Port 5 data register  
P5  
Port 6 data register  
P6  
External interrupt pending register  
External interrupt control register (high byte)  
External interrupt control register (low byte)  
EXTIPND  
EXTICONH  
EXTICONL  
Locations FAH are not mapped.  
STOP control register  
Basic timer counter  
STPCON  
251  
FBH  
FDH  
FFH  
R/W  
R
Locations FCH are not mapped.  
BTCNT  
253  
Locations FEH are not mapped.  
Interrupt priority register  
IPR  
255  
R/W  
4-2  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CONTROL REGISTER  
Table 4-3. Set 1, Bank 1 Registers  
Register Name  
Mnemonic  
Address  
Decimal  
R/W  
Hex  
LCD control Register  
LCON  
224  
225  
226  
227  
228  
229  
230  
231  
232  
233  
234  
235  
236  
237  
E0H  
E1H  
E2H  
E3H  
E4H  
E5H  
E6H  
E7H  
E8H  
E9H  
EAH  
EBH  
ECH  
EDH  
R/W  
R/W  
R
Watch timer control register  
Timer A counter  
WTCON  
TACNT  
Timer B counter  
TBCNT  
R
Timer A data register  
TADATA  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Timer B data register  
TBDATA  
Timer 1/A control register  
Timer B control register  
Clock output control register  
Port 4 control register (high byte)  
Port 4 control register (low byte)  
Port 5 control register (high byte)  
Port 5 control register (low byte)  
Port 6 control register  
TACON  
TBCON  
CLOCON  
P4CONH  
P4CONL  
P5CONH  
P5CONL  
P6CON  
Locations EEH – EFH are not mapped.  
FMCON  
Flash memory control register  
240  
241  
242  
243  
244  
F0H  
F1H  
F2H  
F3H  
F4H  
R/W  
R/W  
R/W  
R/W  
R/W  
Flash memory user programming enable register  
Flash memory sector address register (high byte)  
Flash memory sector address register (low byte)  
Battery level detector control register  
FMUSR  
FMSECH  
FMSECL  
BLDCON  
Locations E5H – FFH are not mapped.  
NOTES:  
1. An “x” means that the bit value is undefined following reset.  
2. A dash(“–“) means that the bit is neither used nor mapped, but the bit is read as “0”.  
4-3  
CONTROL REGISTERS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Bit number(s) that is/are appended to  
the register name for bit addressing  
Name of individual  
bit or related bits  
Register location  
in the internal  
register file  
Register address  
(hexadecimal)  
Register ID  
Full Register name  
FLAGS - System Flags Register  
D5H  
Set 1  
Bit Identifier  
Reset Value  
Read/Write  
Bit Addressing  
Mode  
.7  
x
.6  
x
.5  
x
.4  
x
.3  
x
.2  
.1  
.0  
0
x
x
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Register addressing mode only  
.7  
Carry Flag (C)  
0
1
Operation does not generate a carry or borrow condition  
Operation generates carry-out or borrow into high-order bit 7  
.6  
.5  
Zero Flag (Z)  
Operation result is a non-zero value  
Operation result is zero  
0
1
Sign Flag (S)  
Operation generates positive number (MSB = "0")  
0
1
Operation generates negative number (MSB = "1")  
R = Read-only  
W = Write-only  
R/W = Read/write  
'-' = Not used  
Description of the  
effect of specific  
bit settings  
Bit number:  
MSB = Bit 7  
LSB = Bit 0  
Type of addressing  
that must be used to  
address the bit  
nRESET value notation:  
'-' = Not used  
'x' = Undetermined value  
'0' = Logic zero  
(1-bit, 4-bit, or 8-bit)  
'1' = Logic one  
Figure 4-1. Register Description Format  
4-4  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CONTROL REGISTER  
BLDCON — Battery Level Detector Control Register  
F4H  
Set 1, Bank 1  
Bit Identifier  
Reset Value  
.7  
.6  
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.6  
.5  
Not used for the S3C8275X/C8278X/C8274X  
VIN Source Bit  
0
1
Internal source  
External source  
.4  
Battery Level Detector Output Bit  
VIN > VREF (when BLD is enabled)  
IN < VREF (when BLD is enabled)  
0
1
V
.3  
Battery Level Detector Enable/Disable Bit  
0
1
Disable BLD  
Enable BLD  
.2–.0  
Detection Voltage Selection Bits  
VBLD = 2.2V  
BLD = 2.4V  
VBLD = 2.8V  
0
1
0
0
0
1
0
1
1
V
Other values Not available  
4-5  
CONTROL REGISTERS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
BTCON — Basic Timer Control Register  
D3H  
Set 1  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.4  
.3–.2  
Watchdog Timer Function Disable Code (for System Reset)  
1
0
1
0
Disable watchdog timer function  
Enable watchdog timer function  
Other values  
Basic Timer Input Clock Selection Bits  
fxx/4096 (3)  
fxx/1024  
fxx/128  
0
0
1
1
0
1
0
1
fxx/16  
Basic Timer Counter Clear Bit (1)  
.1  
0
1
No effect  
Clear the basic timer counter value  
Clock Frequency Divider Clear Bit for Basic Timer and Timer/Counters (2)  
.0  
0
1
No effect  
Clear both clock frequency dividers  
NOTES:  
1. When you write a “1” to BTCON.1, the basic timer counter value is cleared to "00H". Immediately following the write  
operation, the BTCON.1 value is automatically cleared to “0”.  
2. When you write a "1" to BTCON.0, the corresponding frequency divider is cleared to "00H". Immediately following the  
write operation, the BTCON.0 value is automatically cleared to "0".  
3. The fxx is selected clock for system (main OSC. or sub OSC.).  
4-6  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CONTROL REGISTER  
CLKCON — System Clock Control Register  
D4H  
Set 1  
Bit Identifier  
Reset Value  
.7  
0
.6  
.5  
.4  
0
.3  
0
.2  
.1  
.0  
Read/Write  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7  
Oscillator IRQ Wake-up Function Bit  
0
1
Enable IRQ for main wake-up in power down mode  
Disable IRQ for main wake-up in power down mode  
.6–.5  
.4–.3  
Not used for the S3C8275X/C8278X/C8274X (must keep always “0”)  
CPU Clock (System Clock) Selection Bits (note)  
0
0
1
1
0
1
0
1
fxx/16  
fxx/8  
fxx/2  
fxx  
.2–.0  
Not used for the S3C8275X/C8278X/C8274X (must keep always “0”)  
NOTE: After a reset, the slowest clock (divided by 16) is selected as the system clock. To select faster clock speeds, load  
the appropriate values to CLKCON.3 and CLKCON.4.  
4-7  
CONTROL REGISTERS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CLOCON — Clock Output Control Register  
E8H  
Set 1, Bank 1  
Bit Identifier  
Reset Value  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.2  
.1–.0  
Not used for the S3C8275X/C8278X/C8274X (must keep always “0”)  
Clock Output Frequency Selection Bits  
0
0
1
1
0
1
0
1
Select fxx/64  
Select fxx/16  
Select fxx/8  
Select fxx/4  
4-8  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CONTROL REGISTER  
EXTICONH External Interrupt Control Register (High Byte)  
F8H  
Set 1, Bank 0  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.6  
.5–.4  
.3–.2  
.1–.0  
P1.7 External Interrupt (INT7) Configuration Bits  
0
0
1
1
0
1
0
1
Disable interrupt  
Enable interrupt by falling edge  
Enable interrupt by rising edge  
Enable interrupt by both falling and rising edge  
P1.6 External Interrupt (INT6) Configuration Bits  
0
0
1
1
0
1
0
1
Disable interrupt  
Enable interrupt by falling edge  
Enable interrupt by rising edge  
Enable interrupt by both falling and rising edge  
P1.5 External Interrupt (INT5) Configuration Bits  
0
0
1
1
0
1
0
1
Disable interrupt  
Enable interrupt by falling edge  
Enable interrupt by rising edge  
Enable interrupt by both falling and rising edge  
P1.4 External Interrupt (INT4) Configuration Bits  
0
0
1
1
0
1
0
1
Disable interrupt  
Enable interrupt by falling edge  
Enable interrupt by rising edge  
Enable interrupt by both falling and rising edge  
4-9  
CONTROL REGISTERS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
EXTICONL External Interrupt Control Register (Low Byte)  
F9H  
Set 1, Bank 0  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.6  
.5–.4  
.3–.2  
.1–.0  
P1.3 External Interrupt (INT3) Configuration Bits  
0
0
1
1
0
1
0
1
Disable interrupt  
Enable interrupt by falling edge  
Enable interrupt by rising edge  
Enable interrupt by both falling and rising edge  
P0.2 External Interrupt (INT2) Configuration Bits  
0
0
1
1
0
1
0
1
Disable interrupt  
Enable interrupt by falling edge  
Enable interrupt by rising edge  
Enable interrupt by both falling and rising edge  
P0.1 External Interrupt (INT1) Configuration Bits  
0
0
1
1
0
1
0
1
Disable interrupt  
Enable interrupt by falling edge  
Enable interrupt by rising edge  
Enable interrupt by both falling and rising edge  
P0.0 External Interrupt (INT0) Configuration Bits  
0
0
1
1
0
1
0
1
Disable interrupt  
Enable interrupt by falling edge  
Enable interrupt by rising edge  
Enable interrupt by both falling and rising edge  
4-10  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CONTROL REGISTER  
EXTIPND — External Interrupt Pending Register  
F7H  
Set 1, Bank 0  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
P1.7/INT7 Interrupt Pending Bit  
0
1
Interrupt request is not pending, pending bit clear when write 0  
Interrupt request is pending (when read)  
P1.6/INT6 Interrupt Pending Bit  
0
1
Interrupt request is not pending, pending bit clear when write 0  
Interrupt request is pending (when read)  
P1.5/INT5 Interrupt Pending Bit  
0
1
Interrupt request is not pending, pending bit clear when write 0  
Interrupt request is pending (when read)  
P1.4/INT4 Interrupt Pending Bit  
0
1
Interrupt request is not pending, pending bit clear when write 0  
Interrupt request is pending (when read)  
P1.3/INT3 Interrupt Pending Bit  
0
1
Interrupt request is not pending, pending bit clear when write 0  
Interrupt request is pending (when read)  
P0.2/INT2 Interrupt Pending Bit  
0
1
Interrupt request is not pending, pending bit clear when write 0  
Interrupt request is pending (when read)  
P0.1/INT1 Interrupt Pending Bit  
0
1
Interrupt request is not pending, pending bit clear when write 0  
Interrupt request is pending (when read)  
P0.0/INT0 Interrupt Pending Bit  
0
1
Interrupt request is not pending, pending bit clear when write 0  
Interrupt request is pending (when read)  
4-11  
CONTROL REGISTERS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
FLAGS — System Flags Register  
D5H  
Set 1  
Bit Identifier  
Reset Value  
.7  
x
.6  
x
.5  
x
.4  
x
.3  
x
.2  
x
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R
R/W  
Addressing Mode  
Register addressing mode only  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
Carry Flag (C)  
0
1
Operation does not generate a carry or borrow condition  
Operation generates a carry-out or borrow into high-order bit 7  
Zero Flag (Z)  
0
1
Operation result is a non-zero value  
Operation result is zero  
Sign Flag (S)  
0
1
Operation generates a positive number (MSB = "0")  
Operation generates a negative number (MSB = "1")  
Overflow Flag (V)  
0
1
Operation result is +127 or –128  
Operation result is > +127 or < –128  
Decimal Adjust Flag (D)  
0
1
Add operation completed  
Subtraction operation completed  
Half-Carry Flag (H)  
0
1
No carry-out of bit 3 or no borrow into bit 3 by addition or subtraction  
Addition generated carry-out of bit 3 or subtraction generated borrow into bit 3  
Fast Interrupt Status Flag (FIS)  
0
1
Interrupt return (IRET) in progress (when read)  
Fast interrupt service routine in progress (when read)  
Bank Address Selection Flag (BA)  
0
1
Bank 0 is selected  
Bank 1 is selected  
4-12  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CONTROL REGISTER  
FMCON — Flash Memory Control Register  
F0H  
Set 1, Bank 1  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
.1  
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R
R/W  
Addressing Mode  
Register addressing mode only  
.7–.4  
Flash Memory Mode Selection Bits  
0
1
0
1
0
1
0
1
1
1
0
0
Programming mode  
Sector erase mode  
Hard lock mode  
Not available  
Other values  
.3  
Sector Erase Status Bit  
0
1
Success sector erase  
Fail sector erase  
.2–.1  
.0  
Not used for the S3F8275X/F8278X/F8274X  
Flash Operation Start Bit  
0
1
Operation stop  
Operation start (This bit will be cleared automatically just after the  
corresponding operator completed).  
4-13  
CONTROL REGISTERS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
FMSECH Flash Memory Sector Address Register (High Byte) F2H  
Set 1, Bank 1  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.0  
Flash Memory Sector Address Bits (High Byte)  
The 15th - 8th bits to select a sector of flash ROM  
NOTE: The high-byte flash memory sector address pointer value is the higher eight bits of the 16-bit pointer address.  
FMSECL Flash Memory Sector Address Register (Low Byte) F3H  
Set 1, Bank 1  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7  
Flash Memory Sector Address Bit (Low Byte)  
The 7th bit to select a sector of flash ROM  
.6–.0  
Bits 6–0  
Don't care  
NOTE: The low-byte flash memory sector address pointer value is the lower eight bits of the 16-bit pointer address.  
4-14  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CONTROL REGISTER  
FMUSR Flash Memory User Programming Enable Register  
F1H  
Set 1, Bank 1  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.0  
Flash Memory User Programming Enable Bits  
1 0 1 0 0 1 0 1 Enable user programming mode  
Other values Disable user programming mode  
4-15  
CONTROL REGISTERS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
IMR — Interrupt Mask Register  
DDH  
Set 1  
Bit Identifier  
Reset Value  
.7  
x
.6  
x
.5  
x
.4  
x
.3  
x
.2  
x
.1  
x
.0  
x
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
Interrupt Level 7 (IRQ7) Enable Bit; External Interrupts P1.4–1.7  
0
1
Disable (mask)  
Enable (unmask)  
Interrupt Level 6 (IRQ6) Enable Bit; External Interrupts P1.3  
0
1
Disable (mask)  
Enable (unmask)  
Interrupt Level 5 (IRQ5) Enable Bit; External Interrupt P0.2  
0
1
Disable (mask)  
Enable (unmask)  
Interrupt Level 4 (IRQ4) Enable Bit; External Interrupt P0.1  
0
1
Disable (mask)  
Enable (unmask)  
Interrupt Level 3 (IRQ3) Enable Bit; External Interrupt P0.0  
0
1
Disable (mask)  
Enable (unmask)  
Interrupt Level 2 (IRQ2) Enable Bit; Watch Timer Overflow  
0
1
Disable (mask)  
Enable (unmask)  
Interrupt Level 1 (IRQ1) Enable Bit; SIO Interrupt  
0
1
Disable (mask)  
Enable (unmask)  
Interrupt Level 0 (IRQ0) Enable Bit; Timer 1/A Match, Timer B Match  
0
1
Disable (mask)  
Enable (unmask)  
NOTE: When an interrupt level is masked, any interrupt requests that may be issued are not recognized by the CPU.  
4-16  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CONTROL REGISTER  
IPH — Instruction Pointer (High Byte)  
DAH  
Set 1  
Bit Identifier  
Reset Value  
.7  
x
.6  
x
.5  
x
.4  
x
.3  
x
.2  
x
.1  
x
.0  
x
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.0  
Instruction Pointer Address (High Byte)  
The high-byte instruction pointer value is the upper eight bits of the 16-bit instruction  
pointer address (IP15–IP8). The lower byte of the IP address is located in the IPL  
register (DBH).  
IPL — Instruction Pointer (Low Byte)  
DBH  
Set 1  
Bit Identifier  
Reset Value  
.7  
x
.6  
x
.5  
x
.4  
x
.3  
x
.2  
x
.1  
x
.0  
x
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.0  
Instruction Pointer Address (Low Byte)  
The low-byte instruction pointer value is the lower eight bits of the 16-bit instruction  
pointer address (IP7–IP0). The upper byte of the IP address is located in the IPH  
register (DAH).  
4-17  
CONTROL REGISTERS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
IPR — Interrupt Priority Register  
FFH  
Set 1, Bank 0  
Bit Identifier  
Reset Value  
.7  
x
.6  
x
.5  
x
.4  
x
.3  
x
.2  
x
.1  
x
.0  
x
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
Priority Control Bits for Interrupt Groups A, B, and C (note)  
.7, .4, and .1  
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
Group priority undefined  
B > C > A  
A > B > C  
B > A > C  
C > A > B  
C > B > A  
A > C > B  
Group priority undefined  
.6  
.5  
.3  
.2  
.0  
Interrupt Subgroup C Priority Control Bit  
0
1
IRQ6 > IRQ7  
IRQ7 > IRQ6  
Interrupt Group C Priority Control Bit  
0
1
IRQ5 > (IRQ6, IRQ7)  
(IRQ6, IRQ7) > IRQ5  
Interrupt Subgroup B Priority Control Bit  
0
1
IRQ3 > IRQ4  
IRQ4 > IRQ3  
Interrupt Group B Priority Control Bit  
0
1
IRQ2 > (IRQ3, IRQ4)  
(IRQ3, IRQ4) > IRQ2  
Interrupt Group A Priority Control Bit  
0
1
IRQ0 > IRQ1  
IRQ1 > IRQ0  
NOTE: Interrupt Group A – IRQ0, IRQ1  
Interrupt Group B – IRQ2, IRQ3, IRQ4  
Interrupt Group C – IRQ5, IRQ6, IRQ7  
4-18  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CONTROL REGISTER  
IRQ — Interrupt Request Register  
DCH  
Set 1  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R
R
R
R
R
R
R
R
Addressing Mode  
Register addressing mode only  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
Level 7 (IRQ7) Request Pending Bit; External Interrupt P1.4–1.7  
0
1
Not pending  
Pending  
Level 6 (IRQ6) Request Pending Bit; External Interrupt P1.3  
0
1
Not pending  
Pending  
Level 5 (IRQ5) Request Pending Bit; External Interrupt P0.2  
0
1
Not pending  
Pending  
Level 4 (IRQ4) Request Pending Bit; External Interrupt P0.1  
0
1
Not pending  
Pending  
Level 3 (IRQ3) Request Pending Bit; External Interrupt P0.0  
0
1
Not pending  
Pending  
Level 2 (IRQ2) Request Pending Bit; Watch Timer Overflow  
0
1
Not pending  
Pending  
Level 1 (IRQ1) Request Pending Bit; SIO Interrupt  
0
1
Not pending  
Pending  
Level 0 (IRQ0) Request Pending Bit; Timer 1/A Match, Timer B Match  
0
1
Not pending  
Pending  
4-19  
CONTROL REGISTERS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
LCON — LCD Control Register  
E0H  
Set 1, Bank 1  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7  
Internal LCD Dividing Resistors Enable Bit  
0
1
Enable internal LCD dividing resistors  
Disable internal LCD dividing resistors  
.6–.5  
LCD Clock Selection Bits  
fw/29 (64 Hz)  
fw/28 (128 Hz)  
fw/27 (256 Hz)  
fw/26 (512 Hz)  
0
0
1
1
0
1
0
1
.4–.2  
LCD Duty and Bias Selection Bits  
0
0
0
0
1
0
0
1
1
x
0
1
0
1
x
1/4duty, 1/3bias  
1/3duty, 1/3bias  
1/3duty, 1/2bias  
1/2duty, 1/2bias  
Static  
NOTES:  
1. "x" means don't care.  
2. When 1/2 bias is selected, the bias levels are set as V  
Not used for the S3C8275X/C8278X/C8274X  
LCD Display Control Bit  
, V  
(V  
), and V  
.
LC0 LC1 LC2  
SS  
.1  
.0  
0
1
Turn display off (Turn off the P-Tr)  
Turn display on (Turn on the P-Tr)  
4-20  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CONTROL REGISTER  
OSCCON — Oscillator Control Register  
E0H  
Set 1, Bank 0  
Bit Identifier  
Reset Value  
.7  
0
.6  
.5  
.4  
.3  
0
.2  
0
.1  
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7  
Sub Oscillator Circuit Selection Bit  
0
1
Initial state  
Power saving circuit for sub oscillator (Automatically cleared to "0" when the  
sub oscillator is stopped by OSCCON.2).  
NOTES:  
1. The OSCCON.7 must be maintained to “1”, during the sub oscillator operation.  
2. A capacitor (0.1uF) should be connected between V  
Not used for the S3C8275X/C8278X/C8274X  
Main Oscillator Control Bit  
and GND.  
REG  
.6–.4  
.3  
0
1
Main oscillator RUN  
Main oscillator STOP  
.2  
Sub Oscillator Control Bit  
0
1
Sub oscillator RUN  
Sub oscillator STOP  
.1  
.0  
Not used for the S3C8275X/C8278X/C8274X  
System Clock Selection Bit  
0
1
Select main oscillator for system clock  
Select sub oscillator for system clock  
4-21  
CONTROL REGISTERS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
P0CONH — Port 0 Control Register (High Byte)  
E4H  
Set 1, Bank 0  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.6  
.5–.4  
.3–.2  
.1–.0  
P0.7/BUZ Configuration Bits  
0
0
1
1
0
1
0
1
Schmitt trigger input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (BUZ)  
P0.6/CLKOUT Configuration Bits  
0
0
1
1
0
1
0
1
Schmitt trigger input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (CLKOUT)  
P0.5/TBOUT Configuration Bits  
0
0
1
1
0
1
0
1
Schmitt trigger input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (TBOUT)  
P0.4/TAOUT Configuration Bits  
0
0
1
1
0
1
0
1
Schmitt trigger input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (TAOUT)  
4-22  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CONTROL REGISTER  
P0CONL — Port 0 Control Register (Low Byte)  
E5H  
Set 1, Bank 0  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.6  
.5–.4  
.3–.2  
.1–.0  
P0.3/T1CLK Configuration Bits  
0
0
1
1
0
1
0
1
Schmitt trigger input mode (T1CLK)  
N-channel open-drain output mode  
Push-pull output mode  
Not used for the S3C8275X/C8278X/C8274X  
P0.2/INT2 Configuration Bits  
0
0
1
1
0
1
0
1
Schmitt trigger input mode  
N-channel open-drain output mode  
Push-pull output mode  
Not used for the S3C8275X/C8278X/C8274X  
P0.1/INT1 Configuration Bits  
0
0
1
1
0
1
0
1
Schmitt trigger input mode  
N-channel open-drain output mode  
Push-pull output mode  
Not used for the S3C8275X/C8278X/C8274X  
P0.0/INT0 Configuration Bits  
0
0
1
1
0
1
0
1
Schmitt trigger input mode  
N-channel open-drain output mode  
Push-pull output mode  
Not used for the S3C8275X/C8278X/C8274X  
4-23  
CONTROL REGISTERS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
P0PUR — Port 0 Pull-Up Control Register  
E6H  
Set 1, Bank 0  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
P0.7's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P0.6's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P0.5's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P0.4's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P0.3's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P0.2's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P0.1's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P0.0's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
NOTE: A pull-up resistor of port 0 is automatically disabled only when the corresponding pin is selected as push-pull output  
or alternative function.  
4-24  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CONTROL REGISTER  
P1CONH — Port 1 Control Register (High Byte)  
E7H  
Set 1, Bank 0  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.6  
.5–.4  
.3–.2  
.1–.0  
P1.7/INT7 Configuration Bits  
0
0
1
1
0
1
0
1
Schmitt trigger input mode  
N-channel open-drain output mode  
Push-pull output mode  
Not used for the S3C8275X/C8278X/C8274X  
P1.6/INT6 Configuration Bits  
0
0
1
1
0
1
0
1
Schmitt trigger input mode  
N-channel open-drain output mode  
Push-pull output mode  
Not used for the S3C8275X/C8278X/C8274X  
P1.5/INT5 Configuration Bits  
0
0
1
1
0
1
0
1
Schmitt trigger input mode  
N-channel open-drain output mode  
Push-pull output mode  
Not used for the S3C8275X/C8278X/C8274X  
P1.4/INT4 Configuration Bits  
0
0
1
1
0
1
0
1
Schmitt trigger input mode  
N-channel open-drain output mode  
Push-pull output mode  
Not used for the S3C8275X/C8278X/C8274X  
4-25  
CONTROL REGISTERS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
P1CONL — Port 1 Control Register (Low Byte)  
E8H  
Set 1, Bank 0  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.6  
.5–.4  
.3–.2  
.1–.0  
P1.3/INT3 Configuration Bits  
0
0
1
1
0
1
0
1
Schmitt trigger input mode  
N-channel open-drain output mode  
Push-pull output mode  
Not used for the S3C8275X/C8278X/C8274X  
P1.2/SI Configuration Bits  
0
0
1
1
0
1
0
1
Schmitt trigger input mode (SI)  
N-channel open-drain output mode  
Push-pull output mode  
Not used for the S3C8275X/C8278X/C8274X  
P1.1/SO Configuration Bits  
0
0
1
1
0
1
0
1
Schmitt trigger input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (SO)  
P1.0/SCK Configuration Bits  
0
0
1
1
0
1
0
1
Schmitt trigger input mode (SCK)  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (SCK)  
4-26  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CONTROL REGISTER  
P1PUR — Port 1 Pull-up Control Register  
F9H  
Set 1, Bank 0  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
P1.7's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P1.6's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P1.5's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P1.4's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P1.3's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P1.2's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P1.1's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P1.0's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
NOTE: A pull-up resistor of port 1 is automatically disabled only when the corresponding pin is selected as push-pull output  
or alternative function.  
4-27  
CONTROL REGISTERS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
P2CONH — Port 2 Control Register (High Byte)  
EAH  
Set 1, Bank 0  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.6  
.5-.4  
.3–.2  
.1–.0  
P2.7/SEG24 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (SEG24)  
P2.6/SEG25 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (SEG25)  
P2.5/SEG26 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (SEG26)  
P2.4/SEG27 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (SEG27)  
4-28  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CONTROL REGISTER  
P2CONL — Port 2 Control Register (Low Byte)  
EBH  
Set 1, Bank 0  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.6  
.5–.4  
.3–.2  
.1–.0  
P2.3/SEG28 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (SEG28)  
P2.2/SEG29 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (SEG29)  
P2.1/SEG30 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (SEG30)  
P2.0/SEG31/VBLDREF Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (SEG31 or VBLDREF  
)
4-29  
CONTROL REGISTERS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
P2PUR — Port 2 Pull-up Control Register  
ECH  
Set 1, Bank 0  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
P2.7's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P2.6's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P2.5's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P2.4's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P2.3's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P2.2's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P2.1's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P2.0's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
NOTE: A pull-up resistor of port 2 is automatically disabled only when the corresponding pin is selected as push-pull output  
or alternative function.  
4-30  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CONTROL REGISTER  
P3CONH — Port 3 Control Register (High Byte)  
EDH  
Set 1, Bank 0  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.6  
.5–.4  
.3–.2  
.1–.0  
P3.7/SEG16 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (SEG16)  
P3.6/SEG17 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (SEG17)  
P3.5/SEG18 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (SEG18)  
P3.4/SEG19 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (SEG19)  
4-31  
CONTROL REGISTERS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
P3CONL — Port 3 Control Register (Low Byte)  
EEH  
Set 1, Bank 0  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.6  
.5–.4  
.3–.2  
.1–.0  
P3.3/SEG20 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (SEG20)  
P3.2/SEG21 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (SEG21)  
P3.1/SEG22 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (SEG22)  
P3.0/SEG23 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (SEG23)  
4-32  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CONTROL REGISTER  
P3PUR — Port 3 Pull-up Control Register  
EFH  
Set 1, Bank 0  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
P3.7's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P3.6's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P3.5's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P3.4's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P3.3's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P3.2's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P3.1's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
P3.0's Pull-up Resistor Enable Bit  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
NOTE: A pull-up resistor of port 3 is automatically disabled only when the corresponding pin is selected as push-pull output  
or alternative function.  
4-33  
CONTROL REGISTERS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
P4CONH — Port 4 Control Register (High Byte)  
E9H  
Set 1, Bank 1  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.6  
.5–.4  
.3–.2  
.1–.0  
P4.7/SEG8 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
Input mode with pull-up resistor  
Push-pull output mode  
Alternative function (SEG8)  
P4.6/SEG9 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
Input mode with pull-up resistor  
Push-pull output mode  
Alternative function (SEG9)  
P4.5/SEG10 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
Input mode with pull-up resistor  
Push-pull output mode  
Alternative function (SEG10)  
P4.4/SEG11 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
Input mode with pull-up resistor  
Push-pull output mode  
Alternative function (SEG11)  
4-34  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CONTROL REGISTER  
P4CONL — Port 4 Control Register (Low Byte)  
EAH  
Set 1, Bank 1  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.6  
.5–.4  
.3–.2  
.1–.0  
P4.3/SEG12 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
Input mode with pull-up resistor  
Push-pull output mode  
Alternative function (SEG12)  
P4.2/SEG13 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
Input mode with pull-up resistor  
Push-pull output mode  
Alternative function (SEG13)  
P4.1/SEG14 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
Input mode with pull-up resistor  
Push-pull output mode  
Alternative function (SEG14)  
P4.0/SEG15 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
Input mode with pull-up resistor  
Push-pull output mode  
Alternative function (SEG15)  
4-35  
CONTROL REGISTERS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
P5CONH — Port 5 Control Register (High Byte)  
EBH  
Set 1, Bank 1  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.6  
.5–.4  
.3–.2  
.1–.0  
P5.7/SEG0 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
Input mode with pull-up resistor  
Push-pull output mode  
Alternative function (SEG0)  
P5.6/SEG1 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
Input mode with pull-up resistor  
Push-pull output mode  
Alternative function (SEG1)  
P5.5/SEG2 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
Input mode with pull-up resistor  
Push-pull output mode  
Alternative function (SEG2)  
P5.4/SEG3 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
Input mode with pull-up resistor  
Push-pull output mode  
Alternative function (SEG3)  
4-36  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CONTROL REGISTER  
P5CONL — Port 5 Control Register (Low Byte)  
ECH  
Set 1, Bank 1  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.6  
.5–.4  
.3–.2  
.1–.0  
P5.3/SEG4 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
Input mode with pull-up resistor  
Push-pull output mode  
Alternative function (SEG4)  
P5.2/SEG5 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
Input mode with pull-up resistor  
Push-pull output mode  
Alternative function (SEG5)  
P5.1/SEG6 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
Input mode with pull-up resistor  
Push-pull output mode  
Alternative function (SEG6)  
P5.0/SEG7 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
Input mode with pull-up resistor  
Push-pull output mode  
Alternative function (SEG7)  
4-37  
CONTROL REGISTERS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
P6CON — Port 6 Control Register  
EDH  
Set 1, Bank 1  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.6  
.5–.4  
.3–.2  
.1–.0  
P6.3/COM3 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
Input mode with pull-up resistor  
Push-pull output mode  
Alternative function (COM3)  
P6.2/COM2 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
Input mode with pull-up resistor  
Push-pull output mode  
Alternative function (COM2)  
P6.1/COM1 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
Input mode with pull-up resistor  
Push-pull output mode  
Alternative function (COM1)  
P6.0/COM0 Configuration Bits  
0
0
1
1
0
1
0
1
Input mode  
Input mode with pull-up resistor  
Push-pull output mode  
Alternative function (COM0)  
4-38  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CONTROL REGISTER  
PP — Register Page Pointer  
DFH  
Set 1  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.4  
Destination Register Page Selection Bits  
0
0
0
0
0
0
0
0
1
0
1
0
Destination: page 0  
Destination: page 1 (Not used for the S3C8278X/C8274X)  
Destination: page 2  
Others  
Not used for the S3C8275X/C8278X/C8274X  
.3– .0  
Source Register Page Selection Bits  
0
0
0
0
0
0
0
0
1
0
1
0
Source: page 0  
Source: page 1 (Not used for the S3C8278X/C8274X)  
Source: page 2  
Others  
Not used for the S3C8275X/C8278X/C8274X  
NOTES:  
1. In the S3C8275X microcontroller, the internal register file is configured as three pages (Pages 0-2).  
The pages 0-1 are used for general purpose register file, and page 2 is used for LCD data register or general  
purpose registers.  
2. In the S3C8278X/C8274X microcontroller, the internal register file is configured as two pages (Pages 0, 2).  
The page 0 is used for general purpose register file, and page 2 is used for LCD data register or general purpose  
registers.  
4-39  
CONTROL REGISTERS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
RP0 — Register Pointer 0  
D6H  
Set 1  
Bit Identifier  
Reset Value  
.7  
1
.6  
1
.5  
0
.4  
0
.3  
0
.2  
.1  
.0  
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing only  
.7–.3  
.2–.0  
Register Pointer 0 Address Value  
Register pointer 0 can independently point to one of the 256-byte working register  
areas in the register file. Using the register pointers RP0 and RP1, you can select  
two 8-byte register slices at one time as active working register space. After a reset,  
RP0 points to address C0H in register set 1, selecting the 8-byte working register  
slice C0H–C7H.  
Not used for the S3C8275X/C8278X/C8274X  
RP1 — Register Pointer 1  
D7H  
Set 1  
Bit Identifier  
Reset Value  
.7  
1
.6  
1
.5  
0
.4  
0
.3  
1
.2  
.1  
.0  
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing only  
.7– .3  
Register Pointer 1 Address Value  
Register pointer 1 can independently point to one of the 256-byte working register  
areas in the register file. Using the register pointers RP0 and RP1, you can select  
two 8-byte register slices at one time as active working register space. After a reset,  
RP1 points to address C8H in register set 1, selecting the 8-byte working register  
slice C8H–CFH.  
.2– .0  
Not used for the S3C8275X/C8278X/C8274X  
4-40  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CONTROL REGISTER  
SIOCON — SIO Control Register  
E1H  
Set 1, Bank 0  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
SIO Shift Clock Selection Bit  
.7  
.6  
.5  
.4  
0
1
Internal clock (P.S clock)  
External clock (SCK)  
Data Direction Control Bit  
0
1
MSB-first mode  
LSB-first mode  
SIO Mode Selection Bit  
0
1
Receive-only mode  
Transmit/receive mode  
Shift Clock Edge Selection Bit  
0
1
Tx at falling edges, Rx at rising edges  
Tx at rising edges, Rx at falling edges  
SIO Counter Clear and Shift Start Bit  
.3  
.2  
.1  
.0  
0
1
No action  
Clear 3-bit counter and start shifting  
SIO Shift Operation Enable Bit  
0
1
Disable shifter and clock counter  
Enable shifter and clock counter  
SIO Interrupt Enable Bit  
0
1
Disable SIO interrupt  
Enable SIO interrupt  
SIO Interrupt Pending Bit  
0
0
No interrupt pending (when read), Clear pending bit (when write)  
Interrupt is pending (when read)  
4-41  
CONTROL REGISTERS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
SPH — Stack Pointer (High Byte)  
D8H  
Set 1  
Bit Identifier  
Reset Value  
.7  
x
.6  
x
.5  
x
.4  
x
.3  
x
.2  
x
.1  
x
.0  
x
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.0  
Stack Pointer Address (High Byte)  
The high-byte stack pointer value is the upper eight bits of the 16-bit stack pointer  
address (SP15–SP8). The lower byte of the stack pointer value is located in register  
SPL (D9H). The SP value is undefined following a reset.  
SPL — Stack Pointer (Low Byte)  
D9H  
Set 1  
Bit Identifier  
Reset Value  
.7  
x
.6  
x
.5  
x
.4  
x
.3  
x
.2  
x
.1  
x
.0  
x
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.0  
Stack Pointer Address (Low Byte)  
The low-byte stack pointer value is the lower eight bits of the 16-bit stack pointer  
address (SP7–SP0). The upper byte of the stack pointer value is located in register  
SPH (D8H). The SP value is undefined following a reset.  
4-42  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CONTROL REGISTER  
STPCON — Stop Control Register  
FBH  
Set 1, Bank 0  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7–.0  
STOP Control Bits  
1 0 1 0 0 1 0 1 Enable stop instruction  
Other values Disable stop instruction  
NOTE: Before execute the STOP instruction, set this STPCON register as “10100101b”. Otherwise the STOP instruction will  
not execute as well as reset will be generated.  
4-43  
CONTROL REGISTERS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
SYM — System Mode Register  
DEH  
Set 1  
Bit Identifier  
Reset Value  
.7  
0
.6  
.5  
.4  
x
.3  
x
.2  
x
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
This bit must remain logic "0"  
.7  
.6–.5  
.4–.2  
Not used for the S3C8275X/C8278X/C8274X  
Fast Interrupt Level Selection Bits (1)  
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
IRQ0  
IRQ1  
IRQ2  
IRQ3  
IRQ4  
IRQ5  
IRQ6  
IRQ7  
Fast Interrupt Enable Bit (2)  
.1  
0
1
Disable fast interrupt processing  
Enable fast interrupt processing  
Global Interrupt Enable Bit (3)  
.0  
0
1
Disable all interrupt processing  
Enable all interrupt processing  
NOTES:  
1. You can select only one interrupt level at a time for fast interrupt processing.  
2. Setting SYM.1 to "1" enables fast interrupt processing for the interrupt level currently selected by SYM.2–SYM.4.  
3. Following a reset, you must enable global interrupt processing by executing an EI instruction  
(not by writing a "1" to SYM.0).  
4-44  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CONTROL REGISTER  
TACON — Timer 1/A Control Register  
E6H  
Set 1, Bank 1  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7  
Timer 1 Operating Mode Selection Bit  
0
1
Two 8-bit timers mode (timer A/B)  
One 16-bit timer mode (timer 1)  
.6–.4  
Timer 1/A Clock Selection Bits  
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
fxx/512  
fxx/256  
fxx/64  
fxx/8  
fxx (system clock)  
fxt (sub clock)  
T1CLK (external clock)  
Not available  
.3  
Timer 1/A Counter Clear Bit  
0
1
No effect  
Clear the timer 1/A counter (when write, automatically cleared to "0" after being  
cleared basic timer counter)  
.2  
.1  
.0  
Timer 1/A Counter Operating Enable Bit  
0
1
Disable counting operation  
Enable counting operation  
Timer 1/A Interrupt Enable Bit  
0
1
Disable interrupt  
Enable interrupt  
Timer 1/A Interrupt Pending Bit  
0
1
No interrupt pending (when read), clear pending bit (when write)  
Interrupt is pending (when read)  
4-45  
CONTROL REGISTERS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
TBCON — Timer B Control Register  
E7H  
Set 1, Bank 1  
Bit Identifier  
Reset Value  
.7  
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7  
Not used for the S3C8275X/C8278X/C8274X  
.6–.4  
Timer B Clock Selection Bits  
0
0
0
0
1
0
0
1
0
1
0
fxx/512  
0
fxx/256  
1
fxx/64  
1
0
fxx/8  
fxt (sub clock)  
Not available  
Others  
.3  
Timer B Counter Clear Bit  
0
1
No effect  
Clear the timer B counter (when write, automatically cleared to "0" after being  
cleared basic timer counter)  
.2  
.1  
.0  
Timer B Counter Operating Enable Bit  
0
1
Disable counting operation  
Enable counting operation  
Timer B Interrupt Enable Bit  
0
1
Disable interrupt  
Enable interrupt  
Timer B Interrupt Pending Bit  
0
1
No interrupt pending (when read), clear pending bit (when write)  
Interrupt is pending (when read)  
4-46  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CONTROL REGISTER  
WTCON — Watch Timer Control Register  
E1H  
Set 1, Bank 1  
Bit Identifier  
Reset Value  
.7  
0
.6  
0
.5  
0
.4  
0
.3  
0
.2  
0
.1  
0
.0  
0
Read/Write  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
Addressing Mode  
Register addressing mode only  
.7  
Watch Timer Clock Selection Bit  
Main system clock divided by 27 (fx/128)  
Sub system clock (fxt)  
0
1
.6  
Watch Timer Interrupt Enable Bit  
0
1
Disable watch timer interrupt  
Enable watch timer interrupt  
.5–.4  
Buzzer Signal Selection Bits  
0
0
1
1
0
1
0
1
0.5 kHz  
1 kHz  
2 kHz  
4 kHz  
.3–.2  
Watch Timer Speed Selection Bits  
0
0
1
1
0
1
0
1
Set watch timer interrupt to 1s  
Set watch timer interrupt to 0.5s  
Set watch timer interrupt to 0.25s  
Set watch timer interrupt to 3.91ms  
.1  
.0  
Watch Timer Enable Bit  
0
1
Disable watch timer; Clear frequency dividing circuits  
Enable watch timer  
Watch Timer Interrupt Pending Bit  
0
1
Interrupt is not pending, clear pending bit when write  
Interrupt is pending  
NOTE: Watch timer clock frequency (fw) is assumed to be 32.768 kHz.  
4-47  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INTERRUPT STRUCTURE  
5
INTERRUPT STRUCTURE  
OVERVIEW  
The S3C8-series interrupt structure has three basic components: levels, vectors, and sources. The SAM8RC  
CPU recognizes up to eight interrupt levels and supports up to 128 interrupt vectors. When a specific interrupt  
level has more than one vector address, the vector priorities are established in hardware. A vector address can be  
assigned to one or more sources.  
Levels  
Interrupt levels are the main unit for interrupt priority assignment and recognition. All peripherals and I/O blocks  
can issue interrupt requests. In other words, peripheral and I/O operations are interrupt-driven. There are eight  
possible interrupt levels: IRQ0IRQ7, also called level 0level 7. Each interrupt level directly corresponds to an  
interrupt request number (IRQn). The total number of interrupt levels used in the interrupt structure varies from  
device to device. The S3C8275X/C8278X/C8274X interrupt structure recognizes eight interrupt levels.  
The interrupt level numbers 0 through 7 do not necessarily indicate the relative priority of the levels. They are just  
identifiers for the interrupt levels that are recognized by the CPU. The relative priority of different interrupt levels is  
determined by settings in the interrupt priority register, IPR. Interrupt group and subgroup logic controlled by IPR  
settings lets you define more complex priority relationships between different levels.  
Vectors  
Each interrupt level can have one or more interrupt vectors, or it may have no vector address assigned at all. The  
maximum number of vectors that can be supported for a given level is 128 (The actual number of vectors used for  
S3C8-series devices is always much smaller). If an interrupt level has more than one vector address, the vector  
priorities are set in hardware. S3C8275X/C8278X/C8274X uses twelve vectors.  
Sources  
A source is any peripheral that generates an interrupt. A source can be an external pin or a counter overflow.  
Each vector can have several interrupt sources. In the S3C8275X/C8278X/C8274X interrupt structure, there are  
twelve possible interrupt sources.  
When a service routine starts, the respective pending bit should be either cleared automatically by hardware or  
cleared "manually" by program software. The characteristics of the source's pending mechanism determine which  
method would be used to clear its respective pending bit.  
5-1  
INTERRUPT STRUCTURE  
INTERRUPT TYPES  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
The three components of the S3C8 interrupt structure described before levels, vectors, and sources are  
combined to determine the interrupt structure of an individual device and to make full use of its available interrupt  
logic. There are three possible combinations of interrupt structure components, called interrupt types 1, 2, and 3.  
The types differ in the number of vectors and interrupt sources assigned to each level (see Figure 5-1):  
Type 1:  
Type 2:  
Type 3:  
One level (IRQn) + one vector (V1) + one source (S1)  
One level (IRQn) + one vector (V1) + multiple sources (S1 Sn)  
One level (IRQn) + multiple vectors (V1 Vn) + multiple sources (S1 Sn , Sn+1 Sn+m  
)
In the S3C8275X/C8278X/C8274X microcontroller, two interrupt types are implemented.  
Levels  
Vectors  
Sources  
Type 1:  
Type 2:  
IRQn  
V
1
S
S
S
S
S
S
S
S
S
S
S
S
1
1
IRQn  
IRQn  
V1  
2
3
n
V1  
V2  
V3  
Vn  
1
Type 3:  
NOTES:  
2
3
n
n +  
n +  
n +  
1
2
1. The number of Sn and Vn value is expandable.  
2. In the S3C8275X/C8278X/C8274X implementation,  
interrupt types 1 and 3 are used.  
m
Figure 5-1. S3C8-Series Interrupt Types  
5-2  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INTERRUPT STRUCTURE  
S3C8275X/C8278X/C8274X INTERRUPT STRUCTURE  
The S3C8275X/C8278X/C8274X microcontroller supports twelve interrupt sources. All twelve of the interrupt  
sources have a corresponding interrupt vector address. Eight interrupt levels are recognized by the CPU in this  
device-specific interrupt structure, as shown in Figure 5-2.  
When multiple interrupt levels are active, the interrupt priority register (IPR) determines the order in which  
contending interrupts are to be serviced. If multiple interrupts occur within the same interrupt level, the interrupt  
with the lowest vector address is usually processed first (The relative priorities of multiple interrupts within a single  
level are fixed in hardware).  
When the CPU grants an interrupt request, interrupt processing starts. All other interrupts are disabled and the  
program counter value and status flags are pushed to stack. The starting address of the service routine is fetched  
from the appropriate vector address (plus the next 8-bit value to concatenate the full 16-bit address) and the  
service routine is executed.  
Levels  
RESET  
IRQ0  
Vectors  
Sources  
Reset/Clear  
100H  
F0H  
H/W  
S/W  
Basic timer overflow  
Timer 1/A match  
S/W  
F2H  
Timer B match  
F4H  
F6H  
S/W  
S/W  
IRQ1  
IRQ2  
SIO interrupt  
Watch timer overflow  
S/W  
S/W  
S/W  
S/W  
IRQ3  
IRQ4  
IRQ5  
IRQ6  
E0H  
E2H  
E4H  
E6H  
P0.0 external interrupt  
P0.1 external interrupt  
P0.2 external interrupt  
P1.3 external interrupt  
S/W  
S/W  
S/W  
S/W  
E8H  
EAH  
ECH  
EEH  
P1.4 external interrupt  
P1.5 external interrupt  
P1.6 external interrupt  
P1.7 external interrupt  
IRQ7  
NOTES:  
1. Within a given interrupt level, the low vector address has high priority.  
For example, F0H has higher priority than F2H within the level IRQ0 the priorities within each  
level are set at the factory.  
2. External interrupts are triggered by a rising or falling edge, depending on the corresponding control  
register setting.  
Figure 5-2. S3C8275X/C8278X/C8274X Interrupt Structure  
5-3  
INTERRUPT STRUCTURE  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INTERRUPT VECTOR ADDRESSES  
All interrupt vector addresses for the S3C8275X/C8278X/C8274X interrupt structure are stored in the vector  
address area of the internal 16-Kbyte ROM, 0H3FFFH, or 8, 4-Kbyte (see Figure 5-3).  
You can allocate unused locations in the vector address area as normal program memory. If you do so, please be  
careful not to overwrite any of the stored vector addresses (Table 5-1 lists all vector addresses).  
The program reset address in the ROM is 0100H.  
The reset address of ROM can be changed by a smart option only in the S3F8275X (Full-Flash Device). Refer to  
the chapter 16. Embedded Flash Memory Interface for more detail contents.  
(Decimal)  
16,383  
(HEX)  
3FFFH  
16-Kbyte  
1FFFH  
0FFFH  
8,191  
4,095  
8-Kbyte  
4-Kbyte  
Internal  
Program Memory  
(ROM) Area  
100H  
FFH  
255  
0
Interrupt Vector Area  
Smart Option Area  
3FH  
3CH  
00H  
Figure 5-3. ROM Vector Address Area  
5-4  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INTERRUPT STRUCTURE  
Request Reset/Clear  
Table 5-1. Interrupt Vectors  
Interrupt Source  
Vector Address  
Decimal  
Hex  
Value  
Interrupt  
Priority in H/W  
Level  
S/W  
Value  
256  
242  
240  
244  
246  
224  
226  
228  
230  
238  
236  
234  
232  
Level  
Reset  
IRQ0  
100H  
F2H  
F0H  
F4H  
F6H  
E0H  
E2H  
E4H  
E6H  
EEH  
ECH  
EAH  
E8H  
Basic timer overflow  
1
0
3
2
1
0
Timer B match  
Timer 1/A match  
SIO interrupt  
IRQ1  
IRQ2  
IRQ3  
IRQ4  
IRQ5  
IRQ6  
IRQ7  
Watch timer overflow  
P0.0 external interrupt  
P0.1 external interrupt  
P0.2 external interrupt  
P1.3 external interrupt  
P1.7 external interrupt  
P1.6 external interrupt  
P1.5 external interrupt  
P1.4 external interrupt  
NOTES:  
1. Interrupt priorities are identified in inverse order: "0" is the highest priority, "1" is the next highest, and so on.  
2. If two or more interrupts within the same level contend, the interrupt with the lowest vector address usually has priority  
over one with a higher vector address. The priorities within a given level are fixed in hardware.  
5-5  
INTERRUPT STRUCTURE  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
ENABLE/DISABLE INTERRUPT INSTRUCTIONS (EI, DI)  
Executing the Enable Interrupts (EI) instruction globally enables the interrupt structure. All interrupts are then  
serviced as they occur according to the established priorities.  
NOTE  
The system initialization routine executed after a reset must always contain an EI instruction to globally  
enable the interrupt structure.  
During the normal operation, you can execute the DI (Disable Interrupt) instruction at any time to globally disable  
interrupt processing. The EI and DI instructions change the value of bit 0 in the SYM register.  
SYSTEM-LEVEL INTERRUPT CONTROL REGISTERS  
In addition to the control registers for specific interrupt sources, four system-level registers control interrupt  
processing:  
The interrupt mask register, IMR, enables (un-masks) or disables (masks) interrupt levels.  
The interrupt priority register, IPR, controls the relative priorities of interrupt levels.  
The interrupt request register, IRQ, contains interrupt pending flags for each interrupt level (as opposed to  
each interrupt source).  
The system mode register, SYM, enables or disables global interrupt processing (SYM settings also enable  
fast interrupts and control the activity of external interface, if implemented).  
Table 5-2. Interrupt Control Register Overview  
Control Register  
ID  
R/W  
Function Description  
Interrupt mask register  
IMR  
R/W  
Bit settings in the IMR register enable or disable interrupt  
processing for each of the eight interrupt levels: IRQ0IRQ7.  
Interrupt priority register  
IPR  
R/W  
Controls the relative processing priorities of the interrupt levels.  
The seven levels of S3C8275X/C8278X/C8274X are organized  
into three groups: A, B, and C. Group A is IRQ0 and IRQ1,  
group B is IRQ2, IRQ3 and IRQ4, and group C is IRQ5, IRQ6,  
and IRQ7.  
Interrupt request register  
System mode register  
IRQ  
R
This register contains a request pending bit for each interrupt  
level.  
SYM  
R/W  
This register enables/disables fast interrupt processing and  
dynamic global interrupt processing.  
NOTE: Before IMR register is changed to any value, all interrupts must be disable. Using DI instruction is recommended.  
5-6  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INTERRUPT PROCESSING CONTROL POINTS  
INTERRUPT STRUCTURE  
Interrupt processing can therefore be controlled in two ways: globally or by specific interrupt level and source. The  
system-level control points in the interrupt structure are:  
— Global interrupt enable and disable (by EI and DI instructions or by direct manipulation of SYM.0 )  
— Interrupt level enable/disable settings (IMR register)  
— Interrupt level priority settings (IPR register)  
— Interrupt source enable/disable settings in the corresponding peripheral control registers  
NOTE  
When writing an application program that handles interrupt processing, be sure to include the necessary  
register file address (register pointer) information.  
EI  
S
R
Q
Interrupt Request Register  
(Read-only)  
Polling  
Cycle  
nRESET  
IRQ0-IRQ7,  
Interrupts  
Interrupt Priority  
Register  
Vector  
Interrupt  
Cycle  
Interrupt Mask  
Register  
Global Interrupt Control (EI,  
DI or SYM.0 manipulation)  
Figure 5-4. Interrupt Function Diagram  
5-7  
INTERRUPT STRUCTURE  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
PERIPHERAL INTERRUPT CONTROL REGISTERS  
For each interrupt source there is one or more corresponding peripheral control registers that let you control the  
interrupt generated by the related peripheral (see Table 5-3).  
Table 5-3. Interrupt Source Control and Data Registers  
Interrupt Source  
Timer B match  
Timer 1/A match  
Interrupt Level  
Register(s)  
Location(s) in Set 1  
IRQ0  
TBCON, TBDATA, TBCNT  
TACON, TADATA, TACNT  
E7H, E5H, E3H, bank 1  
E6H, E4H, E2H, bank 1  
SIO interrupt  
IRQ1  
SIOCON  
SIODATA  
SIOPS  
E1H, bank 0  
E2H, bank 0  
E3H, bank 0  
Watch timer overflow  
P0.0 external interrupt  
IRQ2  
IRQ3  
WTCON  
E1H, bank 1  
P0CONL  
EXTICONL  
EXTIPND  
E5H, bank 0  
F9H, bank 0  
F7H, bank 0  
P0.1 external interrupt  
P0.2 external interrupt  
P1.3 external interrupt  
IRQ4  
IRQ5  
IRQ6  
IRQ7  
P0CONL  
EXTICONL  
EXTIPND  
E5H, bank 0  
F9H, bank 0  
F7H, bank 0  
P0CONL  
EXTICONL  
EXTIPND  
E5H, bank 0  
F9H, bank 0  
F7H, bank 0  
P1CONL  
EXTICONL  
EXTIPND  
E8H, bank 0  
F9H, bank 0  
F7H, bank 0  
P1.7 external interrupt  
P1.6 external interrupt  
P1.5 external interrupt  
P1.4 external interrupt  
P1CONH  
EXTICONH  
EXTIPND  
E7H, bank 0  
F8H, bank 0  
F7H, bank 0  
NOTE: If an interrupt is un-mask (Enable interrupt level) in the IMR register, the pending bit and enable bit of the interrupt  
should be written after a DI instruction is executed.  
5-8  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
SYSTEM MODE REGISTER (SYM)  
INTERRUPT STRUCTURE  
The system mode register, SYM (set 1, DEH), is used to globally enable and disable interrupt processing and to  
control fast interrupt processing (see Figure 5-5).  
A reset clears SYM.1, and SYM.0 to "0". The 3-bit value for fast interrupt level selection, SYM.4SYM.2, is  
undetermined.  
The instructions EI and DI enable and disable global interrupt processing, respectively, by modifying the bit 0  
value of the SYM register. In order to enable interrupt processing an Enable Interrupt (EI) instruction must be  
included in the initialization routine, which follows a reset operation. Although you can manipulate SYM.0 directly  
to enable and disable interrupts during the normal operation, it is recommended to use the EI and DI instructions  
for this purpose.  
System Mode Register (SYM)  
DEH, Set 1, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
Global interrupt enable bit:  
0 = Disable all interrupts processing  
1 = Enable all interrupts processing  
Always logic "0"  
Not used for the  
S3C8275X/C8278X/C8274X  
Fast interrupt enable bit:  
0 = Disable fast interrupts processing  
1 = Enable fast interrupts processing  
Fast interrupt level  
selection bits:  
0 0 0 = IRQ0  
0 0 1 = IRQ1  
0 1 0 = IRQ2  
0 1 1 = IRQ3  
1 0 0 = IRQ4  
1 0 1 = IRQ5  
1 1 0 = IRQ6  
1 1 1 = IRQ7  
NOTES:  
1. You can select only one interrupt level at a time for fast interrupt processing.  
2. Setting SYM.1 to "1" enables fast interrupt processing for the interrupt processing for the  
interrupt level currently selected by SYM.2-SYM.4.  
3. Following a reset, you must enable global interrupt processing by executing EI instruction  
(not by writing a "1" to SYM.0)  
Figure 5-5. System Mode Register (SYM)  
5-9  
INTERRUPT STRUCTURE  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INTERRUPT MASK REGISTER (IMR)  
The interrupt mask register, IMR (set 1, DDH) is used to enable or disable interrupt processing for individual  
interrupt levels. After a reset, all IMR bit values are undetermined and must therefore be written to their required  
settings by the initialization routine.  
Each IMR bit corresponds to a specific interrupt level: bit 1 to IRQ1, bit 2 to IRQ2, and so on. When the IMR bit of  
an interrupt level is cleared to "0", interrupt processing for that level is disabled (masked). When you set a level's  
IMR bit to "1", interrupt processing for the level is enabled (not masked).  
The IMR register is mapped to register location DDH in set 1. Bit values can be read and written by instructions  
using the Register addressing mode.  
Interrupt Mask Register (IMR)  
DDH, Set 1, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
IRQ0  
IRQ1  
IRQ2  
IRQ3  
IRQ4  
IRQ5  
IRQ6  
IRQ7  
Interrupt level enable bits:  
0 = Disable (mask) interrupt level  
1 = Enable (un-mask) interrupt level  
NOTE:  
Before IMR register is changed to any value, all interrupts must be disable.  
Using DI instruction is recommended.  
Figure 5-6. Interrupt Mask Register (IMR)  
5-10  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INTERRUPT PRIORITY REGISTER (IPR)  
INTERRUPT STRUCTURE  
The interrupt priority register, IPR (set 1, bank 0, FFH), is used to set the relative priorities of the interrupt levels in  
the microcontroller’s interrupt structure. After a reset, all IPR bit values are undetermined and must therefore be  
written to their required settings by the initialization routine.  
When more than one interrupt sources are active, the source with the highest priority level is serviced first. If two  
sources belong to the same interrupt level, the source with the lower vector address usually has the priority (This  
priority is fixed in hardware).  
To support programming of the relative interrupt level priorities, they are organized into groups and subgroups by  
the interrupt logic. Please note that these groups (and subgroups) are used only by IPR logic for the IPR register  
priority definitions (see Figure 5-7):  
Group A  
Group B  
Group C  
IRQ0, IRQ1  
IRQ2, IRQ3, IRQ4  
IRQ5, IRQ6, IRQ7  
IPR  
IPR  
IPR  
Group A  
Group B  
Group C  
A1  
A2  
B1  
B2  
C1  
C2  
B21  
B22  
C21  
C22  
IRQ0  
IRQ1  
IRQ2 IRQ3  
IRQ4  
IRQ5 IRQ6  
IRQ7  
Figure 5-7. Interrupt Request Priority Groups  
As you can see in Figure 5-8, IPR.7, IPR.4, and IPR.1 control the relative priority of interrupt groups A, B, and C.  
For example, the setting "001B" for these bits would select the group relationship B > C > A. The setting "101B"  
would select the relationship C > B > A.  
The functions of the other IPR bit settings are as follows:  
IPR.5 controls the relative priorities of group C interrupts.  
Interrupt group C includes a subgroup that has an additional priority relationship among the interrupt levels 5,  
6, and 7. IPR.6 defines the subgroup C relationship. IPR.5 controls the interrupt group C.  
IPR.0 controls the relative priority setting of IRQ0 and IRQ1 interrupts.  
5-11  
INTERRUPT STRUCTURE  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Interrupt Priority Register (IPR)  
FFH, Set 1, Bank 0, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
Group priority:  
D7 D4 D1  
Group A:  
0 = IRQ0 > IRQ1  
1 = IRQ1 > IRQ0  
Group B:  
0 = IRQ2 > (IRQ3, IRQ4)  
1 = (IRQ3, IRQ4) > IRQ2  
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0 = Undefined  
1 = B > C > A  
0 = A > B > C  
1 = B > A > C  
0 = C > A > B  
1 = C > B > A  
0 = A > C > B  
1 = Undefined  
Subgroup B:  
0 = IRQ3 > IRQ4  
1 = IRQ4 > IRQ3  
Group C:  
0 = IRQ5 > (IRQ6, IRQ7)  
1 = (IRQ6, IRQ7) > IRQ5  
Subgroup C:  
0 = IRQ6 > IRQ7  
1 = IRQ7 > IRQ6  
Figure 5-8. Interrupt Priority Register (IPR)  
5-12  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INTERRUPT REQUEST REGISTER (IRQ)  
INTERRUPT STRUCTURE  
You can poll bit values in the interrupt request register, IRQ (set 1, DCH), to monitor interrupt request status for all  
levels in the microcontroller’s interrupt structure. Each bit corresponds to the interrupt level of the same number:  
bit 0 to IRQ0, bit 1 to IRQ1, and so on. A "0" indicates that no interrupt request is currently being issued for that  
level. A "1" indicates that an interrupt request has been generated for that level.  
IRQ bit values are read-only addressable using Register addressing mode. You can read (test) the contents of the  
IRQ register at any time using bit or byte addressing to determine the current interrupt request status of specific  
interrupt levels. After a reset, all IRQ status bits are cleared to “0”.  
You can poll IRQ register values even if a DI instruction has been executed (that is, if global interrupt processing  
is disabled). If an interrupt occurs while the interrupt structure is disabled, the CPU will not service it. You can,  
however, still detect the interrupt request by polling the IRQ register. In this way, you can determine which events  
occurred while the interrupt structure was globally disabled.  
Interrupt Request Register (IRQ)  
DCH, Set 1, Read-only  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
IRQ0  
IRQ1  
IRQ2  
IRQ3  
IRQ4  
IRQ5  
IRQ6  
IRQ7  
Interrupt level request pending bits:  
0 = Interrupt level is not pending  
1 = Interrupt level is pending  
Figure 5-9. Interrupt Request Register (IRQ)  
5-13  
INTERRUPT STRUCTURE  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INTERRUPT PENDING FUNCTION TYPES  
Overview  
There are two types of interrupt pending bits: one type that is automatically cleared by hardware after the interrupt  
service routine is acknowledged and executed; the other that must be cleared in the interrupt service routine.  
Pending Bits Cleared Automatically by Hardware  
For interrupt pending bits that are cleared automatically by hardware, interrupt logic sets the corresponding  
pending bit to "1" when a request occurs. It then issues an IRQ pulse to inform the CPU that an interrupt is waiting  
to be serviced. The CPU acknowledges the interrupt source by sending an IACK, executes the service routine,  
and clears the pending bit to "0". This type of pending bit is not mapped and cannot, therefore, be read or written  
by application software.  
Pending Bits Cleared by the Service Routine  
The second type of pending bit is the one that should be cleared by program software. The service routine must  
clear the appropriate pending bit before a return-from-interrupt subroutine (IRET) occurs. To do this, a "0" must be  
written to the corresponding pending bit location in the source’s mode or control register.  
Programming Tip How to clear an interrupt pending bit  
As the following examples are shown, a load instruction should be used to clear an interrupt pending bit.  
Examples:  
1.  
SB0  
LD  
EXTIPND, #11111011B  
; Clear P0.2's interrupt pending bit  
IRET  
5-14  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INTERRUPT STRUCTURE  
INTERRUPT SOURCE POLLING SEQUENCE  
The interrupt request polling and servicing sequence is as follows:  
1. A source generates an interrupt request by setting the interrupt request bit to "1".  
2. The CPU polling procedure identifies a pending condition for that source.  
3. The CPU checks the source's interrupt level.  
4. The CPU generates an interrupt acknowledge signal.  
5. Interrupt logic determines the interrupt's vector address.  
6. The service routine starts and the source's pending bit is cleared to "0" (by hardware or by software).  
7. The CPU continues polling for interrupt requests.  
INTERRUPT SERVICE ROUTINES  
Before an interrupt request is serviced, the following conditions must be met:  
Interrupt processing must be globally enabled (EI, SYM.0 = "1")  
The interrupt level must be enabled (IMR register)  
The interrupt level must have the highest priority if more than one levels are currently requesting service  
The interrupt must be enabled at the interrupt's source (peripheral control register)  
When all the above conditions are met, the interrupt request is acknowledged at the end of the instruction cycle.  
The CPU then initiates an interrupt machine cycle that completes the following processing sequence:  
1. Reset (clear to "0") the interrupt enable bit in the SYM register (SYM.0) to disable all subsequent interrupts.  
2. Save the program counter (PC) and status flags to the system stack.  
3. Branch to the interrupt vector to fetch the address of the service routine.  
4. Pass control to the interrupt service routine.  
When the interrupt service routine is completed, the CPU issues an Interrupt Return (IRET). The IRET restores  
the PC and status flags, setting SYM.0 to "1". It allows the CPU to process the next interrupt request.  
5-15  
INTERRUPT STRUCTURE  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
GENERATING INTERRUPT VECTOR ADDRESSES  
The interrupt vector area in the ROM (00HFFH) contains the addresses of interrupt service routines that  
correspond to each level in the interrupt structure. Vectored interrupt processing follows this sequence:  
1. Push the program counter's low-byte value to the stack.  
2. Push the program counter's high-byte value to the stack.  
3. Push the FLAG register values to the stack.  
4. Fetch the service routine's high-byte address from the vector location.  
5. Fetch the service routine's low-byte address from the vector location.  
6. Branch to the service routine specified by the concatenated 16-bit vector address.  
NOTE  
A 16-bit vector address always begins at an even-numbered ROM address within the range of 00HFFH.  
NESTING OF VECTORED INTERRUPTS  
It is possible to nest a higher-priority interrupt request while a lower-priority request is being serviced. To do this,  
you must follow these steps:  
1. Push the current 8-bit interrupt mask register (IMR) value to the stack (PUSH IMR).  
2. Load the IMR register with a new mask value that enables only the higher priority interrupt.  
3. Execute an EI instruction to enable interrupt processing (a higher priority interrupt will be processed if it  
occurs).  
4. When the lower-priority interrupt service routine ends, restore the IMR to its original value by returning the  
previous mask value from the stack (POP IMR).  
5. Execute an IRET.  
Depending on the application, you may be able to simplify the procedure above to some extent.  
INSTRUCTION POINTER (IP)  
The instruction pointer (IP) is adopted by all the S3C8-series microcontrollers to control the optional high-speed  
interrupt processing feature called fast interrupts. The IP consists of register pair DAH and DBH. The names of IP  
registers are IPH (high byte, IP15IP8) and IPL (low byte, IP7IP0).  
FAST INTERRUPT PROCESSING  
The feature called fast interrupt processing allows an interrupt within a given level to be completed in  
approximately 6 clock cycles rather than the usual 16 clock cycles. To select a specific interrupt level for fast  
interrupt processing, you write the appropriate 3-bit value to SYM.4SYM.2. Then, to enable fast interrupt  
processing for the selected level, you set SYM.1 to “1”.  
5-16  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INTERRUPT STRUCTURE  
FAST INTERRUPT PROCESSING (Continued)  
Two other system registers support fast interrupt processing:  
The instruction pointer (IP) contains the starting address of the service routine (and is later used to swap the  
program counter values), and  
When a fast interrupt occurs, the contents of the FLAGS register is stored in an unmapped, dedicated register  
called FLAGS' (“FLAGS prime”).  
NOTE  
For the S3C8275X/C8278X/C8274X microcontroller, the service routine for any one of the eight interrupt  
levels: IRQ0–IRQ7, can be selected for fast interrupt processing.  
Procedure for Initiating Fast Interrupts  
To initiate fast interrupt processing, follow these steps:  
1. Load the start address of the service routine into the instruction pointer (IP).  
2. Load the interrupt level number (IRQn) into the fast interrupt selection field (SYM.4–SYM.2)  
3. Write a "1" to the fast interrupt enable bit in the SYM register.  
Fast Interrupt Service Routine  
When an interrupt occurs in the level selected for fast interrupt processing, the following events occur:  
1. The contents of the instruction pointer and the PC are swapped.  
2. The FLAG register values are written to the FLAGS' (“FLAGS prime”) register.  
3. The fast interrupt status bit in the FLAGS register is set.  
4. The interrupt is serviced.  
5. Assuming that the fast interrupt status bit is set, when the fast interrupt service routine ends, the instruction  
pointer and PC values are swapped back.  
6. The content of FLAGS' (“FLAGS prime”) is copied automatically back to the FLAGS register.  
7. The fast interrupt status bit in FLAGS is cleared automatically.  
Relationship to Interrupt Pending Bit Types  
As described previously, there are two types of interrupt pending bits: One type that is automatically cleared by  
hardware after the interrupt service routine is acknowledged and executed; the other that must be cleared by the  
application program's interrupt service routine. You can select fast interrupt processing for interrupts with either  
type of pending condition clear function by hardware or by software.  
Programming Guidelines  
Remember that the only way to enable/disable a fast interrupt is to set/clear the fast interrupt enable bit in the  
SYM register, SYM.1. Executing an EI or DI instruction globally enables or disables all interrupt processing,  
including fast interrupts. If you use fast interrupts, remember to load the IP with a new start address when the fast  
interrupt service routine ends.  
5-17  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
6
INSTRUCTION SET  
OVERVIEW  
The SAM88RC instruction set is specifically designed to support the large register files that are typical of most  
SAM8 microcontrollers. There are 78 instructions. The powerful data manipulation capabilities and features of the  
instruction set include:  
A full complement of 8-bit arithmetic and logic operations, including multiply and divide  
No special I/O instructions (I/O control/data registers are mapped directly into the register file)  
Decimal adjustment included in binary-coded decimal (BCD) operations  
16-bit (word) data can be incremented and decremented  
Flexible instructions for bit addressing, rotate, and shift operations  
DATA TYPES  
The SAM8 CPU performs operations on bits, bytes, BCD digits, and two-byte words. Bits in the register file can  
be set, cleared, complemented, and tested. Bits within a byte are numbered from 7 to 0, where bit 0 is the least  
significant (right-most) bit.  
REGISTER ADDRESSING  
To access an individual register, an 8-bit address in the range 0-255 or the 4-bit address of a working register is  
specified. Paired registers can be used to construct 16-bit data or 16-bit program memory or data memory  
addresses. For detailed information about register addressing, please refer to Section 2, "Address Spaces."  
ADDRESSING MODES  
There are seven explicit addressing modes: Register (R), Indirect Register (IR), Indexed (X), Direct (DA), Relative  
(RA), Immediate (IM), and Indirect (IA). For detailed descriptions of these addressing modes, please refer to  
Section 3, "Addressing Modes."  
6-1  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Table 6-1. Instruction Group Summary  
Operands Instruction  
Mnemonic  
Load Instructions  
CLR  
dst  
Clear  
LD  
dst,src  
dst,src  
dst,src  
dst,src  
dst,src  
dst,src  
dst,src  
dst,src  
dst,src  
dst,src  
dst,src  
dst,src  
dst,src  
dst  
Load  
LDB  
Load bit  
LDE  
Load external data memory  
LDC  
Load program memory  
LDED  
LDCD  
LDEI  
Load external data memory and decrement  
Load program memory and decrement  
Load external data memory and increment  
Load program memory and increment  
Load external data memory with pre-decrement  
Load program memory with pre-decrement  
Load external data memory with pre-increment  
Load program memory with pre-increment  
Load word  
LDCI  
LDEPD  
LDCPD  
LDEPI  
LDCPI  
LDW  
POP  
Pop from stack  
POPUD  
POPUI  
PUSH  
PUSHUD  
PUSHUI  
dst,src  
dst,src  
src  
Pop user stack (decrementing)  
Pop user stack (incrementing)  
Push to stack  
dst,src  
dst,src  
Push user stack (decrementing)  
Push user stack (incrementing)  
6-2  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
Table 6-1. Instruction Group Summary (Continued)  
Operands Instruction  
Mnemonic  
Arithmetic Instructions  
ADC  
ADD  
CP  
dst,src  
Add with carry  
Add  
dst,src  
dst,src  
dst  
Compare  
DA  
Decimal adjust  
Decrement  
Decrement word  
Divide  
DEC  
DECW  
DIV  
dst  
dst  
dst,src  
dst  
INC  
Increment  
INCW  
MULT  
SBC  
SUB  
dst  
Increment word  
Multiply  
dst,src  
dst,src  
dst,src  
Subtract with carry  
Subtract  
Logic Instructions  
AND  
COM  
OR  
dst,src  
dst  
Logical AND  
Complement  
dst,src  
dst,src  
Logical OR  
XOR  
Logical exclusive OR  
6-3  
INSTRUCTION SET  
Mnemonic  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Table 6-1. Instruction Group Summary (Continued)  
Operands Instruction  
Program Control Instructions  
BTJRF  
BTJRT  
CALL  
CPIJE  
CPIJNE  
DJNZ  
ENTER  
EXIT  
IRET  
JP  
dst,src  
dst,src  
dst  
Bit test and jump relative on false  
Bit test and jump relative on true  
Call procedure  
dst,src  
dst,src  
r,dst  
Compare, increment and jump on equal  
Compare, increment and jump on non-equal  
Decrement register and jump on non-zero  
Enter  
Exit  
Interrupt return  
cc,dst  
dst  
Jump on condition code  
Jump unconditional  
JP  
JR  
cc,dst  
Jump relative on condition code  
Next  
NEXT  
RET  
Return  
WFI  
Wait for interrupt  
Bit Manipulation Instructions  
BAND  
BCP  
BITC  
BITR  
BITS  
BOR  
BXOR  
TCM  
TM  
dst,src  
dst,src  
dst  
Bit AND  
Bit compare  
Bit complement  
Bit reset  
dst  
dst  
Bit set  
dst,src  
dst,src  
dst,src  
dst,src  
Bit OR  
Bit XOR  
Test complement under mask  
Test under mask  
6-4  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
Table 6-1. Instruction Group Summary (Concluded)  
Operands Instruction  
Mnemonic  
Rotate and Shift Instructions  
RL  
dst  
dst  
dst  
dst  
dst  
dst  
Rotate left  
RLC  
RR  
Rotate left through carry  
Rotate right  
RRC  
SRA  
SWAP  
Rotate right through carry  
Shift right arithmetic  
Swap nibbles  
CPU Control Instructions  
CCF  
DI  
Complement carry flag  
Disable interrupts  
Enable interrupts  
Enter Idle mode  
No operation  
EI  
IDLE  
NOP  
RCF  
SB0  
SB1  
SCF  
Reset carry flag  
Set bank 0  
Set bank 1  
Set carry flag  
SRP  
src  
src  
src  
Set register pointers  
Set register pointer 0  
Set register pointer 1  
Enter Stop mode  
SRP0  
SRP1  
STOP  
6-5  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
FLAGS REGISTER (FLAGS)  
The flags register FLAGS contains eight bits that describe the current status of CPU operations. Four of these  
bits, FLAGS.7FLAGS.4, can be tested and used with conditional jump instructions; two others FLAGS.3 and  
FLAGS.2 are used for BCD arithmetic.  
The FLAGS register also contains a bit to indicate the status of fast interrupt processing (FLAGS.1) and a bank  
address status bit (FLAGS.0) to indicate whether bank 0 or bank 1 is currently being addressed. FLAGS register  
can be set or reset by instructions as long as its outcome does not affect the flags, such as, Load instruction.  
Logical and Arithmetic instructions such as, AND, OR, XOR, ADD, and SUB can affect the Flags register. For  
example, the AND instruction updates the Zero, Sign and Overflow flags based on the outcome of the AND  
instruction. If the AND instruction uses the Flags register as the destination, then simultaneously, two write will  
occur to the Flags register producing an unpredictable result.  
System Flags Register (FLAGS)  
D5H, Set 1, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
Bank address  
status flag (BA)  
Carry flag (C)  
Fast interrupt  
status flag (FIS)  
Zero flag (Z)  
Sign flag (S)  
Half-carry flag (H)  
Decimal adjust flag (D)  
Overflow flag (V)  
Figure 6-1. System Flags Register (FLAGS)  
6-6  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
FLAG DESCRIPTIONS  
INSTRUCTION SET  
C
Carry Flag (FLAGS.7)  
The C flag is set to "1" if the result from an arithmetic operation generates a carry-out from or a borrow to  
the bit 7 position (MSB). After rotate and shift operations, it contains the last value shifted out of the  
specified register. Program instructions can set, clear, or complement the carry flag.  
Z
Zero Flag (FLAGS.6)  
For arithmetic and logic operations, the Z flag is set to "1" if the result of the operation is zero. For  
operations that test register bits, and for shift and rotate operations, the Z flag is set to "1" if the result is  
logic zero.  
S
V
D
Sign Flag (FLAGS.5)  
Following arithmetic, logic, rotate, or shift operations, the sign bit identifies the state of the MSB of the  
result. A logic zero indicates a positive number and a logic one indicates a negative number.  
Overflow Flag (FLAGS.4)  
The V flag is set to "1" when the result of a two's-complement operation is greater than + 127 or less than  
– 128. It is also cleared to "0" following logic operations.  
Decimal Adjust Flag (FLAGS.3)  
The DA bit is used to specify what type of instruction was executed last during BCD operations, so that a  
subsequent decimal adjust operation can execute correctly. The DA bit is not usually accessed by  
programmers, and cannot be used as a test condition.  
H
Half-Carry Flag (FLAGS.2)  
The H bit is set to "1" whenever an addition generates a carry-out of bit 3, or when a subtraction borrows  
out of bit 4. It is used by the Decimal Adjust (DA) instruction to convert the binary result of a previous  
addition or subtraction into the correct decimal (BCD) result. The H flag is seldom accessed directly by a  
program.  
FIS Fast Interrupt Status Flag (FLAGS.1)  
The FIS bit is set during a fast interrupt cycle and reset during the IRET following interrupt servicing.  
When set, it inhibits all interrupts and causes the fast interrupt return to be executed when the IRET  
instruction is executed.  
BA Bank Address Flag (FLAGS.0)  
The BA flag indicates which register bank in the set 1 area of the internal register file is currently selected,  
bank 0 or bank 1. The BA flag is cleared to "0" (select bank 0) when you execute the SB0 instruction and  
is set to "1" (select bank 1) when you execute the SB1 instruction.  
6-7  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET NOTATION  
Table 6-2. Flag Notation Conventions  
Description  
Flag  
C
Z
Carry flag  
Zero flag  
S
V
D
H
0
Sign flag  
Overflow flag  
Decimal-adjust flag  
Half-carry flag  
Cleared to logic zero  
Set to logic one  
1
*
Set or cleared according to operation  
Value is unaffected  
x
Value is undefined  
Table 6-3. Instruction Set Symbols  
Symbol  
dst  
src  
@
Description  
Destination operand  
Source operand  
Indirect register address prefix  
Program counter  
PC  
IP  
Instruction pointer  
FLAGS  
RP  
#
Flags register (D5H)  
Register pointer  
Immediate operand or register address prefix  
Hexadecimal number suffix  
Decimal number suffix  
Binary number suffix  
Opcode  
H
D
B
opc  
6-8  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
Table 6-4. Instruction Notation Conventions  
Description Actual Operand Range  
Notation  
cc  
r
Condition code  
See list of condition codes in Table 6-6.  
Rn (n = 015)  
Working register only  
rb  
r0  
rr  
Bit (b) of working register  
Rn.b (n = 015, b = 07)  
Rn (n = 015)  
Bit 0 (LSB) of working register  
Working register pair  
RRp (p = 0, 2, 4, ..., 14)  
reg or Rn (reg = 0255, n = 015)  
reg.b (reg = 0255, b = 07)  
R
Register or working register  
Bit 'b' of register or working register  
Register pair or working register pair  
Rb  
RR  
reg or RRp (reg = 0254, even number only, where  
p = 0, 2, ..., 14)  
IA  
Ir  
Indirect addressing mode  
addr (addr = 0–254, even number only)  
@Rn (n = 015)  
Indirect working register only  
IR  
Indirect register or indirect working register  
Indirect working register pair only  
@Rn or @reg (reg = 0255, n = 015)  
@RRp (p = 0, 2, ..., 14)  
Irr  
IRR  
Indirect register pair or indirect working  
register pair  
@RRp or @reg (reg = 0254, even only, where  
p = 0, 2, ..., 14)  
X
Indexed addressing mode  
#reg [Rn] (reg = 0255, n = 015)  
XS  
Indexed (short offset) addressing mode  
#addr [RRp] (addr = range 128 to +127, where  
p = 0, 2, ..., 14)  
xl  
Indexed (long offset) addressing mode  
#addr [RRp] (addr = range 065535, where  
p = 0, 2, ..., 14)  
da  
ra  
Direct addressing mode  
Relative addressing mode  
addr (addr = range 065535)  
addr (addr = number in the range +127 to 128 that is  
an offset relative to the address of the next instruction)  
im  
Immediate addressing mode  
#data (data = 0255)  
iml  
Immediate (long) addressing mode  
#data (data = range 065535)  
6-9  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Table 6-5. Opcode Quick Reference  
OPCODE MAP  
LOWER NIBBLE (HEX)  
0
1
2
3
4
5
6
7
DEC  
R1  
DEC  
IR1  
ADD  
r1,r2  
ADD  
r1,Ir2  
ADD  
R2,R1  
ADD  
IR2,R1  
ADD  
R1,IM  
BOR  
r0–Rb  
U
P
P
E
R
0
1
2
3
4
5
6
7
8
9
A
B
C
D
E
F
RLC  
R1  
RLC  
IR1  
ADC  
r1,r2  
ADC  
r1,Ir2  
ADC  
R2,R1  
ADC  
IR2,R1  
ADC  
R1,IM  
BCP  
r1.b, R2  
INC  
R1  
INC  
IR1  
SUB  
r1,r2  
SUB  
r1,Ir2  
SUB  
R2,R1  
SUB  
IR2,R1  
SUB  
R1,IM  
BXOR  
r0–Rb  
JP  
IRR1  
SRP/0/1  
IM  
SBC  
r1,r2  
SBC  
r1,Ir2  
SBC  
R2,R1  
SBC  
IR2,R1  
SBC  
R1,IM  
BTJR  
r2.b, RA  
DA  
R1  
DA  
IR1  
OR  
r1,r2  
OR  
r1,Ir2  
OR  
R2,R1  
OR  
IR2,R1  
OR  
R1,IM  
LDB  
r0–Rb  
POP  
R1  
POP  
IR1  
AND  
r1,r2  
AND  
r1,Ir2  
AND  
R2,R1  
AND  
IR2,R1  
AND  
R1,IM  
BITC  
r1.b  
COM  
R1  
COM  
IR1  
TCM  
r1,r2  
TCM  
r1,Ir2  
TCM  
R2,R1  
TCM  
IR2,R1  
TCM  
R1,IM  
BAND  
r0–Rb  
N
I
PUSH  
R2  
PUSH  
IR2  
TM  
r1,r2  
TM  
r1,Ir2  
TM  
R2,R1  
TM  
IR2,R1  
TM  
R1,IM  
BIT  
r1.b  
DECW  
RR1  
DECW  
IR1  
PUSHUD PUSHUI  
IR1,R2  
MULT  
R2,RR1  
MULT  
IR2,RR1  
MULT  
IM,RR1  
LD  
r1, x, r2  
B
B
L
E
IR1,R2  
RL  
R1  
RL  
IR1  
POPUD  
IR2,R1  
POPUI  
IR2,R1  
DIV  
R2,RR1  
DIV  
IR2,RR1  
DIV  
IM,RR1  
LD  
r2, x, r1  
INCW  
RR1  
INCW  
IR1  
CP  
r1,r2  
CP  
r1,Ir2  
CP  
R2,R1  
CP  
IR2,R1  
CP  
R1,IM  
LDC  
r1, Irr2, xL  
CLR  
R1  
CLR  
IR1  
XOR  
r1,r2  
XOR  
r1,Ir2  
XOR  
R2,R1  
XOR  
IR2,R1  
XOR  
R1,IM  
LDC  
r2, Irr2, xL  
RRC  
R1  
RRC  
IR1  
CPIJE  
Ir,r2,RA  
LDC  
r1,Irr2  
LDW  
LDW  
LDW  
LD  
r1, Ir2  
RR2,RR1 IR2,RR1 RR1,IML  
SRA  
R1  
SRA  
IR1  
CPIJNE  
Irr,r2,RA  
LDC  
r2,Irr1  
CALL  
IA1  
LD  
IR1,IM  
LD  
Ir1, r2  
H
E
X
RR  
R1  
RR  
IR1  
LDCD  
r1,Irr2  
LDCI  
r1,Irr2  
LD  
R2,R1  
LD  
R2,IR1  
LD  
R1,IM  
LDC  
r1, Irr2, xs  
SWAP  
R1  
SWAP  
IR1  
LDCPD  
r2,Irr1  
LDCPI  
r2,Irr1  
CALL  
IRR1  
LD  
IR2,R1  
CALL  
DA1  
LDC  
r2, Irr1, xs  
6-10  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
Table 6-5. Opcode Quick Reference (Continued)  
OPCODE MAP  
LOWER NIBBLE (HEX)  
8
9
A
B
C
D
E
F
U
P
P
E
R
0
LD  
r1,R2  
LD  
r2,R1  
DJNZ  
r1,RA  
JR  
cc,RA  
LD  
r1,IM  
JP  
cc,DA  
INC  
r1  
NEXT  
1
2
3
4
5
6
7
8
9
A
B
C
D
E
F
ENTER  
EXIT  
WFI  
SB0  
SB1  
IDLE  
STOP  
DI  
N
I
B
B
L
E
EI  
RET  
IRET  
RCF  
SCF  
CCF  
NOP  
H
E
X
LD  
r1,R2  
LD  
r2,R1  
DJNZ  
r1,RA  
JR  
cc,RA  
LD  
r1,IM  
JP  
cc,DA  
INC  
r1  
6-11  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CONDITION CODES  
The opcode of a conditional jump always contains a 4-bit field called the condition code (cc). This specifies under  
which conditions it is to execute the jump. For example, a conditional jump with the condition code for "equal"  
after a compare operation only jumps if the two operands are equal. Condition codes are listed in Table 6-6.  
The carry (C), zero (Z), sign (S), and overflow (V) flags are used to control the operation of conditional jump  
instructions.  
Table 6-6. Condition Codes  
Binary  
Mnemonic  
Description  
Always false  
Flags Set  
0000  
1000  
F
T
Always true  
0111 (note)  
1111 (note)  
0110 (note)  
1110 (note)  
1101  
C
Carry  
C = 1  
C = 0  
Z = 1  
Z = 0  
S = 0  
S = 1  
V = 1  
V = 0  
Z = 1  
Z = 0  
NC  
Z
No carry  
Zero  
NZ  
PL  
MI  
OV  
Not zero  
Plus  
0101  
Minus  
0100  
Overflow  
1100  
NOV  
EQ  
No overflow  
Equal  
0110 (note)  
1110 (note)  
1001  
NE  
Not equal  
GE  
Greater than or equal  
Less than  
(S XOR V) = 0  
(S XOR V) = 1  
(Z OR (S XOR V)) = 0  
(Z OR (S XOR V)) = 1  
C = 0  
0001  
LT  
1010  
GT  
Greater than  
Less than or equal  
Unsigned greater than or equal  
Unsigned less than  
Unsigned greater than  
Unsigned less than or equal  
0010  
LE  
1111 (note)  
0111 (note)  
1011  
UGE  
ULT  
UGT  
ULE  
C = 1  
(C = 0 AND Z = 0) = 1  
(C OR Z) = 1  
0011  
NOTES:  
1. It indicates condition codes that are related to two different mnemonics but which test the same flag. For  
example, Z and EQ are both true if the zero flag (Z) is set, but after an ADD instruction, Z would probably be used;  
after a CP instruction, however, EQ would probably be used.  
2. For operations involving unsigned numbers, the special condition codes UGE, ULT, UGT, and ULE must be used.  
6-12  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION DESCRIPTIONS  
INSTRUCTION SET  
This section contains detailed information and programming examples for each instruction in the SAM8  
instruction set. Information is arranged in a consistent format for improved readability and for fast referencing. The  
following information is included in each instruction description:  
Instruction name (mnemonic)  
Full instruction name  
Source/destination format of the instruction operand  
Shorthand notation of the instruction's operation  
Textual description of the instruction's effect  
Specific flag settings affected by the instruction  
Detailed description of the instruction's format, execution time, and addressing mode(s)  
Programming example(s) explaining how to use the instruction  
6-13  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
ADC — Add with carry  
ADC  
dst,src  
Operation:  
dst  
dst  
+
src  
+
c
The source operand, along with the setting of the carry flag, is added to the destination operand  
and the sum is stored in the destination. The contents of the source are unaffected. Two's-  
complement addition is performed. In multiple precision arithmetic, this instruction permits the  
carry from the addition of low-order operands to be carried into the addition of high-order  
operands.  
Flags:  
C: Set if there is a carry from the most significant bit of the result; cleared otherwise.  
Z: Set if the result is "0"; cleared otherwise.  
S: Set if the result is negative; cleared otherwise.  
V: Set if arithmetic overflow occurs, that is, if both operands are of the same sign and the result  
is of the opposite sign; cleared otherwise.  
D: Always cleared to "0".  
H: Set if there is a carry from the most significant bit of the low-order four bits of the result;  
cleared otherwise.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
opc  
dst | src  
src  
2
4
6
12  
13  
r
r
r
lr  
dst  
3
3
6
6
14  
15  
R
R
R
IR  
opc  
dst  
src  
=
6
16  
R
IM  
Examples:  
Given: R1  
=
10H, R2  
03H, C flag = "1", register 01H  
=
20H, register 02H  
=
03H,  
and register 03H  
=
0AH:  
ADC R1,R2  
R1  
R1  
=
=
14H, R2  
1BH, R2  
=
=
03H  
03H  
ADC R1,@R2  
ADC 01H,02H  
Register 01H  
Register 01H  
Register 01H  
=
=
=
24H, register 02H  
2BH, register 02H  
32H  
=
=
03H  
03H  
ADC 01H,@02H  
ADC 01H,#11H  
In the first example, destination register R1 contains the value 10H, the carry flag is set to "1",  
and the source working register R2 contains the value 03H. The statement "ADC R1,R2" adds  
03H and the carry flag value ("1") to the destination value 10H, leaving 14H in register R1.  
6-14  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
ADD — Add  
ADD  
dst,src  
Operation:  
dst  
dst  
+
src  
The source operand is added to the destination operand and the sum is stored in the destination.  
The contents of the source are unaffected. Two's-complement addition is performed.  
Flags:  
C: Set if there is a carry from the most significant bit of the result; cleared otherwise.  
Z: Set if the result is "0"; cleared otherwise.  
S: Set if the result is negative; cleared otherwise.  
V: Set if arithmetic overflow occurred, that is, if both operands are of the same sign and the  
result is of the opposite sign; cleared otherwise.  
D: Always cleared to "0".  
H: Set if a carry from the low-order nibble occurred.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
opc  
opc  
dst | src  
src  
2
4
6
02  
03  
r
r
r
lr  
dst  
src  
3
3
6
6
04  
05  
R
R
R
IR  
dst  
6
06  
R
IM  
Examples:  
Given: R1 = 12H, R2 = 03H, register 01H = 21H, register 02H = 03H, register 03H = 0AH:  
ADD R1,R2  
R1  
R1  
=
=
15H, R2  
1CH, R2  
=
03H  
03H  
ADD R1,@R2  
ADD 01H,02H  
ADD 01H,@02H  
ADD 01H,#25H  
=
Register 01H  
Register 01H  
Register 01H  
=
=
=
24H, register 02H  
2BH, register 02H  
46H  
=
=
03H  
03H  
In the first example, destination working register R1 contains 12H and the source working register  
R2 contains 03H. The statement "ADD R1,R2" adds 03H to 12H, leaving the value 15H in  
register R1.  
6-15  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
AND — Logical AND  
AND  
dst,src  
Operation:  
dst  
dst AND src  
The source operand is logically ANDed with the destination operand. The result is stored in the  
destination. The AND operation results in a "1" bit being stored whenever the corresponding bits  
in the two operands are both logic ones; otherwise a "0" bit value is stored. The contents of the  
source are unaffected.  
Flags:  
C: Unaffected.  
Z: Set if the result is "0"; cleared otherwise.  
S: Set if the result bit 7 is set; cleared otherwise.  
V: Always cleared to "0".  
D: Unaffected.  
H: Unaffected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
opc  
opc  
dst | src  
src  
2
4
6
52  
53  
r
r
r
lr  
dst  
src  
3
3
6
6
54  
55  
R
R
R
IR  
dst  
6
56  
R
IM  
Examples:  
Given: R1 = 12H, R2  
=
03H, register 01H = 21H, register 02H = 03H, register 03H = 0AH:  
AND R1,R2  
R1  
R1  
=
=
02H, R2  
=
03H  
AND R1,@R2  
AND 01H,02H  
AND 01H,@02H  
AND 01H,#25H  
02H, R2 = 03H  
Register 01H  
Register 01H  
Register 01H  
=
=
=
01H, register 02H  
00H, register 02H  
21H  
=
=
03H  
03H  
In the first example, destination working register R1 contains the value 12H and the source  
working register R2 contains 03H. The statement "AND R1,R2" logically ANDs the source  
operand 03H with the destination operand value 12H, leaving the value 02H in register R1.  
6-16  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
BAND — Bit AND  
BAND  
dst,src.b  
BAND  
dst.b,src  
Operation:  
dst(0)  
dst(b)  
dst(0) AND src(b)  
dst(b) AND src(0)  
or  
The specified bit of the source (or the destination) is logically ANDed with the zero bit (LSB) of  
the destination (or source). The resultant bit is stored in the specified bit of the destination. No  
other bits of the destination are affected. The source is unaffected.  
Flags:  
C: Unaffected.  
Z: Set if the result is "0"; cleared otherwise.  
S: Cleared to "0".  
V: Undefined.  
D: Unaffected.  
H: Unaffected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
opc  
src  
dst  
3
6
67  
r0  
Rb  
dst | b | 0  
src | b | 1  
3
6
67  
Rb  
r0  
NOTE: In the second byte of the 3-byte instruction formats, the destination (or source) address is four bits,  
the bit address 'b' is three bits, and the LSB address value is one bit in length.  
Examples:  
Given: R1 = 07H and register 01H = 05H:  
BAND R1,01H.1  
BAND 01H.1,R1  
R1  
=
06H, register 01H = 05H  
05H, R1 07H  
Register 01H  
=
=
In the first example, source register 01H contains the value 05H (00000101B) and destination  
working register R1 contains 07H (00000111B). The statement "BAND R1,01H.1" ANDs the bit  
1 value of the source register ("0") with the bit 0 value of register R1 (destination), leaving the  
value 06H (00000110B) in register R1.  
6-17  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
BCP — Bit Compare  
BCP  
dst,src.b  
Operation:  
dst(0) – src(b)  
The specified bit of the source is compared to (subtracted from) bit zero (LSB) of the destination.  
The zero flag is set if the bits are the same; otherwise it is cleared. The contents of both  
operands are unaffected by the comparison.  
Flags:  
C: Unaffected.  
Z: Set if the two bits are the same; cleared otherwise.  
S: Cleared to "0".  
V: Undefined.  
D: Unaffected.  
H: Unaffected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
src  
3
6
17  
r0  
Rb  
dst | b | 0  
NOTE: In the second byte of the instruction format, the destination address is four bits, the bit address 'b' is  
three bits, and the LSB address value is one bit in length.  
Example:  
Given: R1  
=
07H and register 01H  
R1  
=
01H:  
BCP R1,01H.1  
=
07H, register 01H  
=
01H  
If destination working register R1 contains the value 07H (00000111B) and the source register  
01H contains the value 01H (00000001B), the statement "BCP R1,01H.1" compares bit one of  
the source register (01H) and bit zero of the destination register (R1). Because the bit values are  
not identical, the zero flag bit (Z) is cleared in the FLAGS register (0D5H).  
6-18  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
BITC — Bit Complement  
BITC  
dst.b  
Operation:  
dst(b) NOT dst(b)  
This instruction complements the specified bit within the destination without affecting any other  
bits in the destination.  
Flags:  
C: Unaffected.  
Z: Set if the result is "0"; cleared otherwise.  
S: Cleared to "0".  
V: Undefined.  
D: Unaffected.  
H: Unaffected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
opc  
2
4
57  
rb  
dst | b | 0  
NOTE: In the second byte of the instruction format, the destination address is four bits, the bit address 'b'  
is three bits, and the LSB address value is one bit in length.  
Example:  
Given: R1  
=
07H  
BITC R1.1  
R1  
=
05H  
If working register R1 contains the value 07H (00000111B), the statement "BITC R1.1"  
complements bit one of the destination and leaves the value 05H (00000101B) in register R1.  
Because the result of the complement is not "0", the zero flag (Z) in the FLAGS register (0D5H) is  
cleared.  
6-19  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
BITR— Bit Reset  
BITR  
dst.b  
Operation:  
dst(b)  
0
The BITR instruction clears the specified bit within the destination without affecting any other bits  
in the destination.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
opc  
2
4
77  
rb  
dst | b | 0  
NOTE: In the second byte of the instruction format, the destination address is four bits, the bit address 'b'  
is three bits, and the LSB address value is one bit in length.  
Example:  
Given: R1  
=
07H:  
BITR R1.1  
R1  
=
05H  
If the value of working register R1 is 07H (00000111B), the statement "BITR R1.1" clears bit  
one of the destination register R1, leaving the value 05H (00000101B).  
6-20  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
BITS— Bit Set  
BITS  
dst.b  
Operation:  
dst(b)  
1
The BITS instruction sets the specified bit within the destination without affecting any other bits in  
the destination.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
opc  
2
4
77  
rb  
dst | b | 1  
NOTE: In the second byte of the instruction format, the destination address is four bits, the bit address 'b'  
is three bits, and the LSB address value is one bit in length.  
Example:  
Given: R1  
=
07H:  
BITS R1.3  
R1  
=
0FH  
If working register R1 contains the value 07H (00000111B), the statement "BITS R1.3" sets bit  
three of the destination register R1 to "1", leaving the value 0FH (00001111B).  
6-21  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
BOR— Bit OR  
BOR  
dst,src.b  
BOR  
dst.b,src  
Operation:  
dst(0)  
dst(b)  
dst(0) OR src(b)  
dst(b) OR src(0)  
or  
The specified bit of the source (or the destination) is logically ORed with bit zero (LSB) of the  
destination (or the source). The resulting bit value is stored in the specified bit of the destination.  
No other bits of the destination are affected. The source is unaffected.  
Flags:  
C: Unaffected.  
Z: Set if the result is "0"; cleared otherwise.  
S: Cleared to "0".  
V: Undefined.  
D: Unaffected.  
H: Unaffected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
opc  
src  
dst  
3
6
07  
r0  
Rb  
dst | b | 0  
src | b | 1  
3
6
07  
Rb  
r0  
NOTE: In the second byte of the 3-byte instruction formats, the destination (or source) address is four bits,  
the bit address 'b' is three bits, and the LSB address value is one bit.  
Examples:  
Given: R1  
=
07H and register 01H  
=
03H:  
BOR R1, 01H.1  
BOR 01H.2, R1  
R1 = 07H, register 01H = 03H  
Register 01H = 07H, R1 = 07H  
In the first example, destination working register R1 contains the value 07H (00000111B) and  
source register 01H the value 03H (00000011B). The statement "BOR R1,01H.1" logically ORs  
bit one of register 01H (source) with bit zero of R1 (destination). This leaves the same value  
(07H) in working register R1.  
In the second example, destination register 01H contains the value 03H (00000011B) and the  
source working register R1 the value 07H (00000111B). The statement "BOR 01H.2,R1" logically  
ORs bit two of register 01H (destination) with bit zero of R1 (source). This leaves the value 07H  
in register 01H.  
6-22  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
BTJRF — Bit Test, Jump Relative on False  
BTJRF  
dst,src.b  
Operation:  
If src(b) is a "0", then PC  
PC  
+
dst  
The specified bit within the source operand is tested. If it is a "0", the relative address is added to  
the program counter and control passes to the statement whose address is now in the PC;  
otherwise, the instruction following the BTJRF instruction is executed.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
(Note 1)  
dst  
src  
opc  
dst  
3
10  
37  
RA  
rb  
src | b | 0  
NOTE: In the second byte of the instruction format, the source address is four bits, the bit address 'b' is  
three bits, and the LSB address value is one bit in length.  
Example:  
Given: R1  
=
07H:  
BTJRF SKIP,R1.3  
PC jumps to SKIP location  
If working register R1 contains the value 07H (00000111B), the statement "BTJRF SKIP,R1.3"  
tests bit 3. Because it is "0", the relative address is added to the PC and the PC jumps to the  
memory location pointed to by the SKIP. (Remember that the memory location must be within the  
allowed range of + 127 to – 128.)  
6-23  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
BTJRT— Bit Test, Jump Relative on True  
BTJRT  
dst,src.b  
Operation:  
If src(b) is a "1", then PC  
PC  
+
dst  
The specified bit within the source operand is tested. If it is a "1", the relative address is added to  
the program counter and control passes to the statement whose address is now in the PC;  
otherwise, the instruction following the BTJRT instruction is executed.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
(Note 1)  
dst  
src  
opc  
dst  
3
10  
37  
RA  
rb  
src | b | 1  
NOTE: In the second byte of the instruction format, the source address is four bits, the bit address 'b' is  
three bits, and the LSB address value is one bit in length.  
Example:  
Given: R1  
=
07H:  
BTJRT  
SKIP,R1.1  
If working register R1 contains the value 07H (00000111B), the statement "BTJRT SKIP,R1.1"  
tests bit one in the source register (R1). Because it is a "1", the relative address is added to the  
PC and the PC jumps to the memory location pointed to by the SKIP. (Remember that the  
memory location must be within the allowed range of + 127 to – 128.)  
6-24  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
BXOR— Bit XOR  
BXOR  
dst,src.b  
BXOR  
dst.b,src  
Operation:  
dst(0)  
dst(b)  
dst(0) XOR src(b)  
dst(b) XOR src(0)  
or  
The specified bit of the source (or the destination) is logically exclusive-ORed with bit zero (LSB)  
of the destination (or source). The result bit is stored in the specified bit of the destination. No  
other bits of the destination are affected. The source is unaffected.  
Flags:  
C: Unaffected.  
Z: Set if the result is "0"; cleared otherwise.  
S: Cleared to "0".  
V: Undefined.  
D: Unaffected.  
H: Unaffected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
opc  
src  
dst  
3
6
27  
r0  
Rb  
dst | b | 0  
src | b | 1  
3
6
27  
Rb  
r0  
NOTE: In the second byte of the 3-byte instruction formats, the destination (or source) address is four bits,  
the bit address 'b' is three bits, and the LSB address value is one bit in length.  
Examples:  
Given: R1  
=
07H (00000111B) and register 01H  
=
03H (00000011B):  
BXOR R1,01H.1  
BXOR 01H.2,R1  
R1  
=
06H, register 01H  
07H, R1  
=
03H  
07H  
Register 01H  
=
=
In the first example, destination working register R1 has the value 07H (00000111B) and source  
register 01H has the value 03H (00000011B). The statement "BXOR R1,01H.1" exclusive-ORs  
bit one of register 01H (source) with bit zero of R1 (destination). The result bit value is stored in  
bit zero of R1, changing its value from 07H to 06H. The value of source register 01H is  
unaffected.  
6-25  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CALL— Call Procedure  
CALL  
dst  
Operation:  
SP  
@SP  
SP  
@SP  
PC  
SP – 1  
PCL  
SP –1  
PCH  
dst  
The current contents of the program counter are pushed onto the top of the stack. The program  
counter value used is the address of the first instruction following the CALL instruction. The  
specified destination address is then loaded into the program counter and points to the first  
instruction of a procedure. At the end of the procedure the return instruction (RET) can be used  
to return to the original program flow. RET pops the top of the stack back into the program  
counter.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
opc  
opc  
dst  
3
14  
F6  
F4  
D4  
DA  
IRR  
IA  
dst  
dst  
2
12  
14  
opc  
2
Examples:  
Given: R0  
=
35H, R1 = 21H, PC  
=
1A47H, and SP  
=
0002H:  
CALL 3521H →  
SP  
=
0000H  
(Memory locations 0000H  
=
1AH, 0001H  
=
4AH, where  
4AH is the address that follows the instruction.)  
SP = 0000H (0000H 1AH, 0001H 49H)  
SP 0000H (0000H 1AH, 0001H 49H)  
CALL @RR0 →  
=
=
CALL #40H  
=
=
=
In the first example, if the program counter value is 1A47H and the stack pointer contains the  
value 0002H, the statement "CALL 3521H" pushes the current PC value onto the top of the  
stack. The stack pointer now points to memory location 0000H. The PC is then loaded with the  
value 3521H, the address of the first instruction in the program sequence to be executed.  
If the contents of the program counter and stack pointer are the same as in the first example, the  
statement "CALL @RR0" produces the same result except that the 49H is stored in stack  
location 0001H (because the two-byte instruction format was used). The PC is then loaded with  
the value 3521H, the address of the first instruction in the program sequence to be executed.  
Assuming that the contents of the program counter and stack pointer are the same as in the first  
example, if program address 0040H contains 35H and program address 0041H contains 21H, the  
statement "CALL #40H" produces the same result as in the second example.  
6-26  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
CCF— Complement Carry Flag  
CCF  
Operation:  
C
NOT  
The carry flag (C) is complemented. If C  
zero; if C  
C
=
"1", the value of the carry flag is changed to logic  
=
"0", the value of the carry flag is changed to logic one.  
Flags:  
C: Complemented.  
No other flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
opc  
1
4
EF  
Example:  
Given: The carry flag  
CCF  
=
"0":  
If the carry flag  
=
"0", the CCF instruction complements it in the FLAGS register (0D5H),  
changing its value from logic zero to logic one.  
6-27  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CLR— Clear  
CLR  
dst  
Operation:  
dst  
"0"  
The destination location is cleared to "0".  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
opc  
dst  
2
4
4
B0  
B1  
R
IR  
Examples:  
Given: Register 00H  
=
4FH, register 01H  
=
02H, and register 02H  
=
5EH:  
CLR  
CLR  
00H  
Register 00H  
Register 01H  
=
=
00H  
02H, register 02H  
@01H →  
=
00H  
In Register (R) addressing mode, the statement "CLR 00H" clears the destination register 00H  
value to 00H. In the second example, the statement "CLR @01H" uses Indirect Register (IR)  
addressing mode to clear the 02H register value to 00H.  
6-28  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
COM— Complement  
COM  
dst  
Operation:  
dst  
NOT dst  
The contents of the destination location are complemented (one's complement); all "1s" are  
changed to "0s", and vice-versa.  
Flags:  
C: Unaffected.  
Z: Set if the result is "0"; cleared otherwise.  
S: Set if the result bit 7 is set; cleared otherwise.  
V: Always reset to "0".  
D: Unaffected.  
H: Unaffected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
opc  
dst  
2
4
4
60  
61  
R
IR  
Examples:  
Given: R1  
=
07H and register 07H  
=
0F1H:  
COM R1  
R1  
R1  
=
=
0F8H  
07H, register 07H  
COM @R1  
=
0EH  
In the first example, destination working register R1 contains the value 07H (00000111B). The  
statement "COM R1" complements all the bits in R1: all logic ones are changed to logic zeros,  
and vice-versa, leaving the value 0F8H (11111000B).  
In the second example, Indirect Register (IR) addressing mode is used to complement the value  
of destination register 07H (11110001B), leaving the new value 0EH (00001110B).  
6-29  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CP— Compare  
CP  
dst,src  
Operation:  
dst – src  
The source operand is compared to (subtracted from) the destination operand, and the  
appropriate flags are set accordingly. The contents of both operands are unaffected by the  
comparison.  
Flags:  
C: Set if a "borrow" occurred (src > dst); cleared otherwise.  
Z: Set if the result is "0"; cleared otherwise.  
S: Set if the result is negative; cleared otherwise.  
V: Set if arithmetic overflow occurred; cleared otherwise.  
D: Unaffected.  
H: Unaffected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
opc  
opc  
dst | src  
src  
2
4
6
A2  
A3  
r
r
r
lr  
dst  
3
3
6
6
A4  
A5  
R
R
R
IR  
dst  
src  
6
A6  
R
IM  
Examples:  
1. Given: R1  
CP  
=
02H and R2  
=
03H:  
R1,R2 →  
Set the C and S flags  
Destination working register R1 contains the value 02H and source register R2 contains the value  
03H. The statement "CP R1,R2" subtracts the R2 value (source/subtrahend) from the R1 value  
(destination/minuend). Because a "borrow" occurs and the difference is negative, C and S are  
"1".  
2. Given: R1 = 05H and R2 = 0AH:  
CP  
JP  
INC  
R1,R2  
UGE,SKIP  
R1  
SKIP LD  
R3,R1  
In this example, destination working register R1 contains the value 05H which is less than the  
contents of the source working register R2 (0AH). The statement "CP R1,R2" generates C = "1"  
and the JP instruction does not jump to the SKIP location. After the statement "LD R3,R1"  
executes, the value 06H remains in working register R3.  
6-30  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
CPIJE— Compare, Increment, and Jump on Equal  
CPIJE  
dst,src,RA  
Operation:  
If dst – src  
=
"0", PC  
PC  
+
RA  
Ir  
Ir  
+
1
The source operand is compared to (subtracted from) the destination operand. If the result is "0",  
the relative address is added to the program counter and control passes to the statement whose  
address is now in the program counter. Otherwise, the instruction immediately following the  
CPIJE instruction is executed. In either case, the source pointer is incremented by one before the  
next instruction is executed.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
src dst  
RA  
3
12  
C2  
r
Ir  
NOTE: Execution time is 18 cycles if the jump is taken or 16 cycles if it is not taken.  
Example:  
Given: R1  
=
02H, R2  
=
03H, and register 03H  
=
02H:  
CPIJE R1,@R2,SKIP →  
R2 04H, PC jumps to SKIP location  
=
In this example, working register R1 contains the value 02H, working register R2 the value 03H,  
and register 03 contains 02H. The statement "CPIJE R1,@R2,SKIP" compares the @R2 value  
02H (00000010B) to 02H (00000010B). Because the result of the comparison is equal, the  
relative address is added to the PC and the PC then jumps to the memory location pointed to by  
SKIP. The source register (R2) is incremented by one, leaving a value of 04H. (Remember that  
the memory location must be within the allowed range of + 127 to – 128.)  
6-31  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CPIJNE— Compare, Increment, and Jump on Non-Equal  
CPIJNE  
dst,src,RA  
Operation:  
If dst – src  
"0", PC  
+ 1  
PC  
+
RA  
Ir  
Ir  
The source operand is compared to (subtracted from) the destination operand. If the result is not  
"0", the relative address is added to the program counter and control passes to the statement  
whose address is now in the program counter; otherwise the instruction following the CPIJNE  
instruction is executed. In either case the source pointer is incremented by one before the next  
instruction.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
src dst  
RA  
3
12  
D2  
r
Ir  
NOTE: Execution time is 18 cycles if the jump is taken or 16 cycles if it is not taken.  
Example:  
Given: R1  
=
02H, R2  
=
03H, and register 03H  
=
04H:  
CPIJNER1,@R2,SKIP →  
R2 04H, PC jumps to SKIP location  
=
Working register R1 contains the value 02H, working register R2 (the source pointer) the value  
03H, and general register 03 the value 04H. The statement "CPIJNE R1,@R2,SKIP" subtracts  
04H (00000100B) from 02H (00000010B). Because the result of the comparison is non-equal, the  
relative address is added to the PC and the PC then jumps to the memory location pointed to by  
SKIP. The source pointer register (R2) is also incremented by one, leaving a value of 04H.  
(Remember that the memory location must be within the allowed range of + 127 to – 128.)  
6-32  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
DA— Decimal Adjust  
DA  
dst  
Operation:  
dst  
DA dst  
The destination operand is adjusted to form two 4-bit BCD digits following an addition or  
subtraction operation. For addition (ADD, ADC) or subtraction (SUB, SBC), the following table  
indicates the operation performed. (The operation is undefined if the destination operand was not  
the result of a valid addition or subtraction of BCD digits):  
Instruction  
Carry  
Before DA  
Bits 4–7  
Value (Hex)  
H Flag  
Before DA  
Bits 0–3  
Value (Hex)  
Number Added  
to Byte  
Carry  
After DA  
0
0
0
0
0
0
1
1
1
0
0
1
1
0–9  
0–8  
0–9  
A–F  
9–F  
A–F  
0–2  
0–2  
0–3  
0–9  
0–8  
7–F  
6–F  
0
0
1
0
0
1
0
0
1
0
1
0
1
0–9  
A–F  
0–3  
0–9  
A–F  
0–3  
0–9  
A–F  
0–3  
0–9  
6–F  
0–9  
6–F  
00  
06  
06  
60  
66  
66  
60  
66  
66  
0
0
0
1
1
1
1
1
1
0
0
1
1
ADD  
ADC  
00  
FA  
A0  
9A  
=
=
=
=
– 00  
– 06  
– 60  
– 66  
SUB  
SBC  
Flags:  
C: Set if there was a carry from the most significant bit; cleared otherwise (see table).  
Z: Set if result is "0"; cleared otherwise.  
S: Set if result bit 7 is set; cleared otherwise.  
V: Undefined.  
D: Unaffected.  
H: Unaffected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
opc  
dst  
2
4
4
40  
41  
R
IR  
6-33  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
DA— Decimal Adjust  
DA  
(Continued)  
Example:  
Given: Working register R0 contains the value 15 (BCD), working register R1 contains  
27 (BCD), and address 27H contains 46 (BCD):  
ADD  
DA  
R1,R0  
R1  
;
;
C "0", H "0", Bits 4–7 = 3, bits 0–3 = C, R1 3CH  
R1 3CH + 06  
If addition is performed using the BCD values 15 and 27, the result should be 42. The sum is  
incorrect, however, when the binary representations are added in the destination location using  
standard binary arithmetic:  
0 0 0 1  
+ 0 0 1 0  
0 1 0 1  
0 1 1 1  
15  
27  
0 0 1 1  
1 1 0 0 =  
3CH  
The DA instruction adjusts this result so that the correct BCD representation is obtained:  
0 0 1 1  
+ 0 0 0 0  
1 1 0 0  
0 1 1 0  
0 1 0 0  
0 0 1 0 =  
42  
Assuming the same values given above, the statements  
SUB  
DA  
27H,R0 ;  
@R1  
C "0", H "0", Bits 4–7 = 3, bits 0–3 = 1  
@R1 31–0  
;
leave the value 31 (BCD) in address 27H (@R1).  
6-34  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
DEC— Decrement  
DEC  
dst  
Operation:  
dst  
dst – 1  
The contents of the destination operand are decremented by one.  
Flags:  
C: Unaffected.  
Z: Set if the result is "0"; cleared otherwise.  
S: Set if result is negative; cleared otherwise.  
V: Set if arithmetic overflow occurred; cleared otherwise.  
D: Unaffected.  
H: Unaffected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
opc  
dst  
2
4
4
00  
01  
R
IR  
Examples:  
Given: R1  
=
03H and register 03H  
=
10H:  
0FH  
DEC R1  
R1  
=
02H  
DEC @R1  
Register 03H  
=
In the first example, if working register R1 contains the value 03H, the statement "DEC R1"  
decrements the hexadecimal value by one, leaving the value 02H. In the second example, the  
statement "DEC @R1" decrements the value 10H contained in the destination register 03H by  
one, leaving the value 0FH.  
6-35  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
DECW— Decrement Word  
DECW  
dst  
Operation:  
dst  
dst – 1  
The contents of the destination location (which must be an even address) and the operand  
following that location are treated as a single 16-bit value that is decremented by one.  
Flags:  
C: Unaffected.  
Z: Set if the result is "0"; cleared otherwise.  
S: Set if the result is negative; cleared otherwise.  
V: Set if arithmetic overflow occurred; cleared otherwise.  
D: Unaffected.  
H: Unaffected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
opc  
dst  
2
8
8
80  
81  
RR  
IR  
Examples:  
21H:  
Given: R0  
=
12H, R1  
=
34H, R2  
12H, R1  
=
30H, register 30H = 0FH, and register 31H  
= 33H  
=
DECW RR0  
DECW @R2  
R0  
=
Register 30H  
=
0FH, register 31H  
=
20H  
In the first example, destination register R0 contains the value 12H and register R1 the value  
34H. The statement "DECW RR0" addresses R0 and the following operand R1 as a 16-bit word  
and decrements the value of R1 by one, leaving the value 33H.  
NOTE:  
A system malfunction may occur if you use a Zero flag (FLAGS.6) result together with a DECW  
instruction. To avoid this problem, we recommend that you use DECW as shown in the following  
example:  
LOOP: DECW RR0  
LD  
OR  
JR  
R2,R1  
R2,R0  
NZ,LOOP  
6-36  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
DI— Disable Interrupts  
DI  
Operation:  
SYM (0)  
0
Bit zero of the system mode control register, SYM.0, is cleared to "0", globally disabling all  
interrupt processing. Interrupt requests will continue to set their respective interrupt pending bits,  
but the CPU will not service them while interrupt processing is disabled.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
opc  
1
4
8F  
Example:  
Given: SYM  
DI  
=
01H:  
If the value of the SYM register is 01H, the statement "DI" leaves the new value 00H in the  
register and clears SYM.0 to "0", disabling interrupt processing.  
Before changing IMR, interrupt pending and interrupt source control register, be sure DI state.  
6-37  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
DIV— Divide (Unsigned)  
DIV  
dst,src  
Operation:  
dst  
÷
src  
dst (UPPER)  
dst (LOWER)  
REMAINDER  
QUOTIENT  
The destination operand (16 bits) is divided by the source operand (8 bits). The quotient (8 bits)  
is stored in the lower half of the destination. The remainder (8 bits) is stored in the upper half of  
8
the destination. When the quotient is 2 , the numbers stored in the upper and lower halves of  
the destination for quotient and remainder are incorrect. Both operands are treated as unsigned  
integers.  
Flags:  
C: Set if the V flag is set and quotient is between 28 and 29 –1; cleared otherwise.  
Z: Set if divisor or quotient  
S: Set if MSB of quotient  
=
"0"; cleared otherwise.  
"1"; cleared otherwise.  
=
V: Set if quotient is  
D: Unaffected.  
H: Unaffected.  
28 or if divisor  
=
"0"; cleared otherwise.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
RR  
RR  
RR  
src  
opc  
src  
dst  
3
26/10  
26/10  
26/10  
94  
95  
96  
R
IR  
IM  
NOTE: Execution takes 10 cycles if the divide-by-zero is attempted; otherwise it takes 26 cycles.  
Examples:  
Given: R0  
=
10H, R1  
=
03H, R2  
=
40H, register 40H  
=
80H:  
DIV  
DIV  
DIV  
RR0,R2  
R0  
R0  
R0  
=
=
=
03H, R1  
03H, R1  
03H, R1  
=
=
=
40H  
20H  
80H  
RR0,@R2  
RR0,#20H  
In the first example, destination working register pair RR0 contains the values 10H (R0) and 03H  
(R1), and register R2 contains the value 40H. The statement "DIV RR0,R2" divides the 16-bit  
RR0 value by the 8-bit value of the R2 (source) register. After the DIV instruction, R0 contains the  
value 03H and R1 contains 40H. The 8-bit remainder is stored in the upper half of the destination  
register RR0 (R0) and the quotient in the lower half (R1).  
6-38  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
DJNZ— Decrement and Jump if Non-Zero  
DJNZ  
r,dst  
Operation:  
r
r
1
If  
r
0, PC  
PC  
+
dst  
The working register being used as a counter is decremented. If the contents of the register are  
not logic zero after decrementing, the relative address is added to the program counter and  
control passes to the statement whose address is now in the PC. The range of the relative  
address is +127 to –128, and the original value of the PC is taken to be the address of the  
instruction byte following the DJNZ statement.  
NOTE: In case of using DJNZ instruction, the working register being used as a counter should be set at  
the one of location 0C0H to 0CFH with SRP, SRP0, or SRP1 instruction.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
r
|
opc  
dst  
2
8
(jump taken)  
(no jump)  
rA  
RA  
8
r = 0 to F  
Example:  
Given: R1  
=
02H and LOOP is the label of a relative address:  
SRP  
#0C0H  
DJNZ R1,LOOP  
DJNZ is typically used to control a "loop" of instructions. In many cases, a label is used as the  
destination operand instead of a numeric relative address value. In the example, working register  
R1 contains the value 02H, and LOOP is the label for a relative address.  
The statement "DJNZ R1, LOOP" decrements register R1 by one, leaving the value 01H.  
Because the contents of R1 after the decrement are non-zero, the jump is taken to the relative  
address specified by the LOOP label.  
6-39  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
EI— Enable Interrupts  
EI  
Operation:  
SYM (0)  
1
An EI instruction sets bit zero of the system mode register, SYM.0 to "1". This allows interrupts to  
be serviced as they occur (assuming they have highest priority). If an interrupt's pending bit was  
set while interrupt processing was disabled (by executing a DI instruction), it will be serviced  
when you execute the EI instruction.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
opc  
1
4
9F  
Example:  
Given: SYM  
EI  
=
00H:  
If the SYM register contains the value 00H, that is, if interrupts are currently disabled, the  
statement "EI" sets the SYM register to 01H, enabling all interrupts. (SYM.0 is the enable bit for  
global interrupt processing.)  
6-40  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
ENTER— Enter  
ENTER  
Operation:  
SP  
@SP  
IP  
SP – 2  
IP  
PC  
PC  
IP  
@IP  
IP + 2  
This instruction is useful when implementing threaded-code languages. The contents of the  
instruction pointer are pushed to the stack. The program counter (PC) value is then written to the  
instruction pointer. The program memory word that is pointed to by the instruction pointer is  
loaded into the PC, and the instruction pointer is incremented by two.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
opc  
1
14  
1F  
Example:  
The diagram below shows one example of how to use an ENTER statement.  
Before  
After  
Data  
Address  
IP  
Data  
Address  
IP  
0050  
0040  
0022  
0043  
0110  
0020  
Address  
Data  
1F  
Address  
40 Enter  
Data  
1F  
PC  
SP  
40 Enter  
PC  
SP  
41 Address H 01  
42 Address L 10  
43 Address H  
41 Address H 01  
42 Address L 10  
43 Address H  
20  
21  
22  
00  
50  
IPH  
IPL  
Data  
110 Routine  
Memory  
Memory  
22  
Data  
Stack  
Stack  
6-41  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
EXIT— Exit  
EXIT  
Operation:  
IP  
@SP  
SP  
SP  
PC  
IP  
+
2
@IP  
IP  
+
2
This instruction is useful when implementing threaded-code languages. The stack value is  
popped and loaded into the instruction pointer. The program memory word that is pointed to by  
the instruction pointer is then loaded into the program counter, and the instruction pointer is  
incremented by two.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode (Hex)  
opc  
1
14 (internal stack)  
16 (internal stack)  
2F  
Example:  
The diagram below shows one example of how to use an EXIT statement.  
Before  
After  
Data  
Address  
IP  
Data  
Address  
IP  
0050  
0040  
0022  
0052  
0060  
0022  
Address  
Data  
Address  
Data  
PC  
SP  
PC  
SP  
50 PCL old  
51 PCH  
60  
00  
60  
Main  
140 Exit  
2F  
20  
21  
22  
00  
50  
IPH  
IPL  
Data  
Memory  
Memory  
Data  
22  
Stack  
Stack  
6-42  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
IDLE— Idle Operation  
IDLE  
Operation:  
The IDLE instruction stops the CPU clock while allowing system clock oscillation to continue. Idle  
mode can be released by an interrupt request (IRQ) or an external reset operation.  
In application programs, a IDLE instruction must be immediately followed by at least three NOP  
instructions. This ensures an adeguate time interval for the clock to stabilize before the next  
instruction is executed. If three or more NOP instructons are not used after IDLE instruction,  
leakage current could be flown because of the floating state in the internal bus.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
1
4
6F  
Example:  
The instruction  
IDLE  
NOP  
NOP  
NOP  
;
stops the CPU clock but not the system clock  
6-43  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INC— Increment  
INC  
dst  
Operation:  
dst  
dst  
+
1
The contents of the destination operand are incremented by one.  
Flags:  
C: Unaffected.  
Z: Set if the result is "0"; cleared otherwise.  
S: Set if the result is negative; cleared otherwise.  
V: Set if arithmetic overflow occurred; cleared otherwise.  
D: Unaffected.  
H: Unaffected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
dst  
|
opc  
1
4
rE  
r
r = 0 to F  
opc  
dst  
2
4
4
20  
21  
R
IR  
Examples:  
Given: R0  
=
1BH, register 00H  
=
0CH, and register 1BH  
=
0FH:  
INC  
INC  
INC  
R0  
R0  
Register 00H  
R0 1BH, register 01H  
=
1CH  
00H  
@R0  
=
0DH  
=
=
10H  
In the first example, if destination working register R0 contains the value 1BH, the statement "INC  
R0" leaves the value 1CH in that same register.  
The next example shows the effect an INC instruction has on register 00H, assuming that it  
contains the value 0CH.  
In the third example, INC is used in Indirect Register (IR) addressing mode to increment the  
value of register 1BH from 0FH to 10H.  
6-44  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
INCW— Increment Word  
INCW  
dst  
Operation:  
dst  
dst  
+
1
The contents of the destination (which must be an even address) and the byte following that  
location are treated as a single 16-bit value that is incremented by one.  
Flags:  
C: Unaffected.  
Z: Set if the result is "0"; cleared otherwise.  
S: Set if the result is negative; cleared otherwise.  
V: Set if arithmetic overflow occurred; cleared otherwise.  
D: Unaffected.  
H: Unaffected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
opc  
dst  
2
8
8
A0  
A1  
RR  
IR  
Examples:  
Given: R0  
=
1AH, R1  
=
02H, register 02H  
=
0FH, and register 03H  
=
0FFH:  
INCW RR0  
INCW @R1  
R0  
=
1AH, R1 = 03H  
10H, register 03H  
Register 02H  
=
=
00H  
In the first example, the working register pair RR0 contains the value 1AH in register R0 and 02H  
in register R1. The statement "INCW RR0" increments the 16-bit destination by one, leaving the  
value 03H in register R1. In the second example, the statement "INCW @R1" uses Indirect  
Register (IR) addressing mode to increment the contents of general register 03H from 0FFH to  
00H and register 02H from 0FH to 10H.  
NOTE:  
A system malfunction may occur if you use a Zero (Z) flag (FLAGS.6) result together with an  
INCW instruction. To avoid this problem, we recommend that you use INCW as shown in the  
following example:  
LOOP:  
INCW  
LD  
OR  
RR0  
R2,R1  
R2,R0  
NZ,LOOP  
JR  
6-45  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
IRET— Interrupt Return  
IRET  
IRET (Normal)  
IRET (Fast)  
Operation:  
FLAGS  
SP  
@SP  
PC  
FLAGS  
FIS  
IP  
0
SP  
PC  
SP  
+
1
FLAGS'  
@SP  
SP  
+
2
SYM(0)  
1
This instruction is used at the end of an interrupt service routine. It restores the flag register and  
the program counter. It also re-enables global interrupts. A "normal IRET" is executed only if the  
fast interrupt status bit (FIS, bit one of the FLAGS register, 0D5H) is cleared (= "0"). If a fast  
interrupt occurred, IRET clears the FIS bit that was set at the beginning of the service routine.  
Flags:  
All flags are restored to their original settings (that is, the settings before the interrupt occurred).  
Format:  
IRET  
Bytes  
Cycles  
Opcode (Hex)  
(Normal)  
opc  
1
10 (internal stack)  
12 (internal stack)  
BF  
IRET  
Bytes  
Cycles  
Opcode (Hex)  
(Fast)  
opc  
1
6
BF  
Example:  
In the figure below, the instruction pointer is initially loaded with 100H in the main program before  
interrupts are enabled. When an interrupt occurs, the program counter and instruction pointer are  
swapped. This causes the PC to jump to address 100H and the IP to keep the return address.  
The last instruction in the service routine normally is a jump to IRET at address FFH. This causes  
the instruction pointer to be loaded with 100H "again" and the program counter to jump back to  
the main program. Now, the next interrupt can occur and the IP is still correct at 100H.  
0H  
FFH  
IRET  
100H  
Interrupt  
Service  
Routine  
JP to FFH  
FFFFH  
NOTE:  
In the fast interrupt example above, if the last instruction is not a jump to IRET, you must pay  
attention to the order of the last two instructions. The IRET cannot be immediately proceded by a  
clearing of the interrupt status (as with a reset of the IPR register).  
6-46  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
JP— Jump  
JP  
cc,dst  
(Conditional)  
JP  
dst  
(Unconditional)  
Operation:  
If cc is true, PC  
dst  
The conditional JUMP instruction transfers program control to the destination address if the  
condition specified by the condition code (cc) is true; otherwise, the instruction following the JP  
instruction is executed. The unconditional JP simply replaces the contents of the PC with the  
contents of the specified register pair. Control then passes to the statement addressed by the  
PC.  
Flags:  
No flags are affected.  
Format: (1)  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
(2)  
cc  
|
opc  
dst  
3
8
ccD  
DA  
cc = 0 to F  
opc  
dst  
2
8
30  
IRR  
NOTES:  
1. The 3-byte format is used for a conditional jump and the 2-byte format for an unconditional jump.  
2. In the first byte of the three-byte instruction format (conditional jump), the condition code and the  
opcode are both four bits.  
Examples:  
Given: The carry flag (C)  
=
"1", register 00  
=
01H, and register 01  
=
20H:  
JP  
JP  
C,LABEL_W  
@00H  
LABEL_W  
=
1000H, PC  
=
1000H  
PC 0120H  
=
The first example shows a conditional JP. Assuming that the carry flag is set to "1", the statement  
"JP C,LABEL_W" replaces the contents of the PC with the value 1000H and transfers control to  
that location. Had the carry flag not been set, control would then have passed to the statement  
immediately following the JP instruction.  
The second example shows an unconditional JP. The statement "JP @00" replaces the  
contents of the PC with the contents of the register pair 00H and 01H, leaving the value 0120H.  
6-47  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
JR— Jump Relative  
JR  
cc,dst  
Operation:  
If cc is true, PC  
PC  
+
dst  
If the condition specified by the condition code (cc) is true, the relative address is added to the  
program counter and control passes to the statement whose address is now in the program  
counter; otherwise, the instruction following the JR instruction is executed. (See list of condition  
codes).  
The range of the relative address is +127, –128, and the original value of the program counter  
is taken to be the address of the first instruction byte following the JR statement.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
(1)  
cc  
|
opc  
dst  
2
6
ccB  
RA  
cc = 0 to F  
NOTE: In the first byte of the two-byte instruction format, the condition code and the opcode are each  
four bits.  
Example:  
Given: The carry flag = "1" and LABEL_X  
=
1FF7H:  
JR C,LABEL_X PC 1FF7H  
=
If the carry flag is set (that is, if the condition code is true), the statement "JR C,LABEL_X" will  
pass control to the statement whose address is now in the PC. Otherwise, the program  
instruction following the JR would be executed.  
6-48  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
LD— Load  
LD  
dst,src  
dst  
Operation:  
src  
The contents of the source are loaded into the destination. The source's contents are unaffected.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
IM  
R
dst  
src  
|
opc  
opc  
src  
dst  
|
2
4
4
rC  
r8  
r
r
|
2
2
3
3
4
r9  
R
r
r = 0 to F  
opc  
opc  
opc  
dst  
src  
4
4
C7  
D7  
r
lr  
r
Ir  
src  
dst  
dst  
src  
6
6
E4  
E5  
R
R
R
IR  
6
6
E6  
D6  
R
IM  
IM  
IR  
opc  
opc  
opc  
src  
dst  
x
3
3
3
6
6
6
F5  
87  
97  
IR  
r
R
x [r]  
r
dst  
src  
|
|
src  
dst  
x
x [r]  
6-49  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
LD— Load  
LD  
(Continued)  
Examples:  
Given: R0  
=
01H, R1  
=
0AH, register 00H  
=
01H, register 01H = 20H,  
register 02H  
=
02H, LOOP  
=
30H, and register 3AH = 0FFH:  
LD  
LD  
LD  
LD  
LD  
LD  
LD  
LD  
LD  
LD  
LD  
LD  
R0,#10H  
R0,01H  
01H,R0  
R1,@R0  
@R0,R1  
00H,01H  
R0  
R0  
=
=
10H  
20H, register 01H = 20H  
Register 01H  
=
01H, R0 = 01H  
R1  
R0  
=
=
20H, R0  
01H, R1  
=
=
01H  
0AH, register 01H = 0AH  
Register 00H  
Register 02H  
Register 00H  
Register 00H  
Register 00H  
=
=
=
=
=
20H, register 01H = 20H  
20H, register 00H = 01H  
0AH  
02H,@00H  
00H,#0AH  
@00H,#10H  
@00H,02H  
01H, register 01H = 10H  
01H, register 01H = 02, register 02H = 02H  
R0,#LOOP[R1] →  
#LOOP[R0],R1 →  
R0  
=
0FFH, R1  
=
0AH  
Register 31H  
=
0AH, R0 = 01H, R1 = 0AH  
6-50  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
LDB— Load Bit  
LDB  
dst,src.b  
LDB  
dst.b,src  
Operation:  
dst(0)  
dst(b)  
src(b)  
src(0)  
or  
The specified bit of the source is loaded into bit zero (LSB) of the destination, or bit zero of the  
source is loaded into the specified bit of the destination. No other bits of the destination are  
affected. The source is unaffected.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
opc  
src  
dst  
3
6
47  
r0  
Rb  
dst | b | 0  
src | b | 1  
3
6
47  
Rb  
r0  
NOTE: In the second byte of the instruction formats, the destination (or source) address is four bits, the bit  
address 'b' is three bits, and the LSB address value is one bit in length.  
Examples:  
Given: R0  
=
06H and general register 00H  
=
05H:  
LDB  
LDB  
R0,00H.2  
00H.0,R0  
R0  
R0  
=
=
07H, register 00H  
06H, register 00H  
=
=
05H  
04H  
In the first example, destination working register R0 contains the value 06H and the source  
general register 00H the value 05H. The statement "LD R0,00H.2" loads the bit two value of the  
00H register into bit zero of the R0 register, leaving the value 07H in register R0.  
In the second example, 00H is the destination register. The statement "LD 00H.0,R0" loads bit  
zero of register R0 to the specified bit (bit zero) of the destination register, leaving 04H in general  
register 00H.  
6-51  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
LDC/LDE— Load Memory  
LDC/LDE  
dst,src  
Operation:  
dst  
src  
This instruction loads a byte from program or data memory into a working register or vice-versa.  
The source values are unaffected. LDC refers to program memory and LDE to data memory. The  
assembler makes 'Irr' or 'rr' values an even number for program memory and odd an odd number  
for data memory.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
1.  
2.  
3.  
4.  
5.  
opc  
opc  
opc  
opc  
opc  
dst | src  
src | dst  
dst | src  
src | dst  
dst | src  
2
10  
C3  
D3  
E7  
F7  
A7  
r
Irr  
2
3
3
4
10  
12  
12  
14  
Irr  
r
XS  
XS  
r
XS [rr]  
r
XS [rr]  
r
XLL  
XLH  
XLH  
DAH  
DAH  
DAH  
DAH  
XL [rr]  
XLL  
DAL  
DAL  
DAL  
DAL  
6.  
7.  
opc  
opc  
opc  
opc  
opc  
src | dst  
dst | 0000  
src | 0000  
dst | 0001  
src | 0001  
4
4
4
4
4
14  
14  
14  
14  
14  
B7  
A7  
B7  
A7  
B7  
XL [rr]  
r
DA  
r
r
8.  
DA  
r
9.  
DA  
r
10.  
DA  
NOTES:  
1.  
2.  
The source (src) or working register pair [rr] for formats 5 and 6 cannot use register pair 0–1.  
For formats 3 and 4, the destination address 'XS [rr]' and the source address 'XS [rr]' are each  
one byte.  
3.  
4.  
For formats 5 and 6, the destination address 'XL [rr] and the source address 'XL [rr]' are each two  
bytes.  
The DA and r source values for formats 7 and 8 are used to address program memory; the  
second set of values, used in formats 9 and 10, are used to address data memory.  
6-52  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
LDC/LDE— Load Memory  
LDC/LDE  
(Continued)  
Examples:  
Given: R0  
=
11H, R1  
=
=
34H, R2  
1A, 0105H  
=
01H, R3  
6DH, and 1104H  
7DH, and 1104H  
=
04H; Program memory locations  
88H. External data memory  
98H:  
0103H  
=
4FH, 0104H  
=
=
locations 0103H  
=
5FH, 0104H  
=
2AH, 0105H  
=
=
LDC  
LDE  
R0,@RR2  
; R0  
; R0  
contents of program memory location 0104H  
1AH, R2 01H, R3 04H  
=
=
=
R0,@RR2  
; R0  
; R0  
=
contents of external data memory location 0104H  
2AH, R2 01H, R3 04H  
=
=
LDC (note) @RR2,R0  
; 11H (contents of R0) is loaded into program memory  
; location 0104H (RR2),  
; working registers R0, R2, R3  
no change  
LDE  
LDC  
LDE  
@RR2,R0  
; 11H (contents of R0) is loaded into external data memory  
; location 0104H (RR2),  
; working registers R0, R2, R3  
no change  
R0,#01H[RR2]  
R0,#01H[RR2]  
; R0  
; (01H + RR2),  
contents of program memory location 0105H  
; R0  
; R0  
=
6DH, R2  
=
01H, R3  
=
04H  
contents of external data memory location 0105H  
7DH, R2 01H, R3 04H  
; (01H + RR2), R0  
=
=
=
LDC (note) #01H[RR2],R0  
; 11H (contents of R0) is loaded into program memory location  
; 0105H (01H + 0104H)  
LDE  
LDC  
LDE  
#01H[RR2],R0  
; 11H (contents of R0) is loaded into external data memory  
; location 0105H (01H + 0104H)  
R0,#1000H[RR2] ; R0  
contents of program memory location 1104H  
88H, R2 01H, R3 04H  
; (1000H + 0104H), R0  
=
=
=
R0,#1000H[RR2] ; R0  
contents of external data memory location 1104H  
98H, R2 01H, R3 04H  
; (1000H + 0104H), R0  
=
=
=
LDC  
LDE  
R0,1104H  
R0,1104H  
; R0  
contents of program memory location 1104H, R0=88H  
; R0  
; R0  
=
contents of external data memory location 1104H,  
98H  
LDC (note) 1105H,R0  
; 11H (contents of R0) is loaded into program memory location  
; 1105H, (1105H) 11H  
LDE  
1105H,R0  
; 11H (contents of R0) is loaded into external data memory  
; location 1105H, (1105H) 11H  
NOTE: These instructions are not supported by masked ROM type devices.  
6-53  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
LDCD/LDED— Load Memory and Decrement  
LDCD/LDED dst,src  
Operation:  
dst  
rr  
src  
rr – 1  
These instructions are used for user stacks or block transfers of data from program or data  
memory to the register file. The address of the memory location is specified by a working register  
pair. The contents of the source location are loaded into the destination location. The memory  
address is then decremented. The contents of the source are unaffected.  
LDCD references program memory and LDED references external data memory. The assembler  
makes 'Irr' an even number for program memory and an odd number for data memory.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
dst | src  
2
10  
E2  
r
Irr  
Examples:  
Given: R6 = 10H, R7 = 33H, R8 = 12H, program memory location 1033H = 0CDH, and external  
data memory location 1033H 0DDH:  
=
LDCD  
R8,@RR6  
; 0CDH (contents of program memory location 1033H) is loaded  
; into R8 and RR6 is decremented by one  
; R8  
=
0CDH, R6  
=
10H, R7  
=
32H (RR6  
RR6 – 1)  
LDED  
R8,@RR6  
; 0DDH (contents of data memory location 1033H) is loaded  
; into R8 and RR6 is decremented by one (RR6 RR6 – 1)  
; R8 0DDH, R6 10H, R7 32H  
=
=
=
6-54  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
LDCI/LDEI— Load Memory and Increment  
LDCI/LDEI  
dst,src  
Operation:  
dst  
rr  
src  
rr  
+
1
These instructions are used for user stacks or block transfers of data from program or data  
memory to the register file. The address of the memory location is specified by a working register  
pair. The contents of the source location are loaded into the destination location. The memory  
address is then incremented automatically. The contents of the source are unaffected.  
LDCI refers to program memory and LDEI refers to external data memory. The assembler makes  
'Irr' even for program memory and odd for data memory.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
dst | src  
2
10  
E3  
r
Irr  
Examples:  
Given: R6  
=
10H, R7 = 33H, R8 = 12H, program memory locations 1033H = 0CDH and  
1034H  
=
0C5H; external data memory locations 1033H 0DDH and 1034H 0D5H:  
=
=
LDCI  
R8,@RR6  
; 0CDH (contents of program memory location 1033H) is loaded  
; into R8 and RR6 is incremented by one (RR6 RR6 + 1)  
; R8 0CDH, R6 10H, R7 34H  
=
=
=
LDEI  
R8,@RR6  
; 0DDH (contents of data memory location 1033H) is loaded  
; into R8 and RR6 is incremented by one (RR6 RR6 + 1)  
; R8 0DDH, R6 10H, R7 34H  
=
=
=
6-55  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
LDCPD/LDEPD— Load Memory with Pre-Decrement  
LDCPD/  
LDEPD  
dst,src  
Operation:  
rr  
rr  
1
dst  
src  
These instructions are used for block transfers of data from program or data memory from the  
register file. The address of the memory location is specified by a working register pair and is first  
decremented. The contents of the source location are then loaded into the destination location.  
The contents of the source are unaffected.  
LDCPD refers to program memory and LDEPD refers to external data memory. The assembler  
makes 'Irr' an even number for program memory and an odd number for external data memory.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
src | dst  
2
14  
F2  
Irr  
r
Examples:  
Given: R0  
=
77H, R6  
=
30H, and R7  
=
00H:  
LDCPD @RR6,R0  
; (RR6 RR6 – 1)  
; 77H (contents of R0) is loaded into program memory location  
; 2FFFH (3000H – 1H)  
; R0  
=
77H, R6  
=
2FH, R7  
=
0FFH  
LDEPD @RR6,R0  
; (RR6  
RR6 – 1)  
; 77H (contents of R0) is loaded into external data memory  
; location 2FFFH (3000H – 1H)  
; R0  
=
77H, R6  
=
2FH, R7  
=
0FFH  
6-56  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
LDCPI/LDEPI— Load Memory with Pre-Increment  
LDCPI/  
LDEPI  
dst,src  
Operation:  
rr  
rr  
+
1
dst  
src  
These instructions are used for block transfers of data from program or data memory from the  
register file. The address of the memory location is specified by a working register pair and is first  
incremented. The contents of the source location are loaded into the destination location. The  
contents of the source are unaffected.  
LDCPI refers to program memory and LDEPI refers to external data memory. The assembler  
makes 'Irr' an even number for program memory and an odd number for data memory.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
src | dst  
2
14  
F3  
Irr  
r
Examples:  
Given: R0  
LDCPI  
=
7FH, R6  
=
21H, and R7  
=
0FFH:  
@RR6,R0  
; (RR6 RR6 + 1)  
; 7FH (contents of R0) is loaded into program memory  
; location 2200H (21FFH + 1H)  
; R0  
=
7FH, R6  
=
22H, R7  
=
00H  
LDEPI  
@RR6,R0  
; (RR6  
RR6 + 1)  
; 7FH (contents of R0) is loaded into external data memory  
; location 2200H (21FFH + 1H)  
; R0  
=
7FH, R6  
=
22H, R7  
=
00H  
6-57  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
LDW— Load Word  
LDW  
dst,src  
Operation:  
dst  
src  
The contents of the source (a word) are loaded into the destination. The contents of the source  
are unaffected.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
RR  
RR  
src  
RR  
IR  
opc  
opc  
src  
dst  
dst  
3
8
8
C4  
C5  
src  
4
8
C6  
RR  
IML  
Examples:  
Given: R4  
=
06H, R5  
=
1CH, R6  
=
05H, R7  
=
02H, register 00H  
=
1AH,  
register 01H  
=
02H, register 02H  
=
03H, and register 03H  
=
0FH:  
LDW  
LDW  
RR6,RR4  
00H,02H  
R6  
=
06H, R7 1CH, R4  
=
=
06H, R5  
0FH,  
=
1CH  
Register 00H  
register 02H  
=
03H, register 01H  
03H, register 03H  
=
=
=
0FH  
LDW  
LDW  
LDW  
LDW  
RR2,@R7  
R2  
Register 04H  
R6 12H, R7  
Register 02H  
=
03H, R3  
=
0FH,  
03H, register 05H  
34H  
0FH, register 03H  
04H,@01H  
RR6,#1234H  
02H,#0FEDH  
=
=
=
0FH  
=
=
=
0EDH  
In the second example, please note that the statement "LDW 00H,02H" loads the contents of  
the source word 02H, 03H into the destination word 00H, 01H. This leaves the value 03H in  
general register 00H and the value 0FH in register 01H.  
The other examples show how to use the LDW instruction with various addressing modes and  
formats.  
6-58  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
MULT— Multiply (Unsigned)  
MULT  
dst,src  
Operation:  
dst  
dst × src  
The 8-bit destination operand (even register of the register pair) is multiplied by the source  
operand (8 bits) and the product (16 bits) is stored in the register pair specified by the destination  
address. Both operands are treated as unsigned integers.  
Flags:  
C: Set if result is > 255; cleared otherwise.  
Z: Set if the result is "0"; cleared otherwise.  
S: Set if MSB of the result is a "1"; cleared otherwise.  
V: Cleared.  
D: Unaffected.  
H: Unaffected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
RR  
RR  
RR  
src  
opc  
src  
dst  
3
22  
22  
22  
84  
85  
86  
R
IR  
IM  
Examples:  
Given: Register 00H  
=
20H, register 01H = 03H, register 02H  
=
09H, register 03H = 06H:  
MULT  
MULT  
MULT  
00H, 02H  
Register 00H = 01H, register 01H = 20H, register 02H = 09H  
00H, @01H  
00H, #30H  
Register 00H  
Register 00H  
=
=
00H, register 01H  
=
0C0H  
06H, register 01H = 00H  
In the first example, the statement "MULT 00H,02H" multiplies the 8-bit destination operand (in  
the register 00H of the register pair 00H, 01H) by the source register 02H operand (09H). The  
16-bit product, 0120H, is stored in the register pair 00H, 01H.  
6-59  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
NEXT— Next  
NEXT  
Operation:  
PC  
IP  
@ IP  
IP  
+
2
The NEXT instruction is useful when implementing threaded-code languages. The program  
memory word that is pointed to by the instruction pointer is loaded into the program counter. The  
instruction pointer is then incremented by two.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
opc  
1
10  
0F  
Example:  
The following diagram shows one example of how to use the NEXT instruction.  
Before  
After  
Data  
Address  
IP  
Data  
Address  
IP  
0043  
0120  
0045  
0130  
Address  
Data  
Address  
43 Address H  
Data  
PC  
43 Address H 01  
PC  
44 Address L 10  
45 Address H  
44 Address L  
45 Address H  
120 Next  
Memory  
130 Routine  
Memory  
6-60  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
NOP— No Operation  
NOP  
Operation:  
No action is performed when the CPU executes this instruction. Typically, one or more NOPs are  
executed in sequence in order to effect a timing delay of variable duration.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
opc  
1
4
FF  
Example:  
When the instruction  
NOP  
is encountered in a program, no operation occurs. Instead, there is a delay in instruction  
execution time.  
6-61  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
OR— Logical OR  
OR  
dst,src  
Operation:  
dst  
dst OR src  
The source operand is logically ORed with the destination operand and the result is stored in the  
destination. The contents of the source are unaffected. The OR operation results in a "1" being  
stored whenever either of the corresponding bits in the two operands is a "1"; otherwise a "0" is  
stored.  
Flags:  
C: Unaffected.  
Z: Set if the result is "0"; cleared otherwise.  
S: Set if the result bit 7 is set; cleared otherwise.  
V: Always cleared to "0".  
D: Unaffected.  
H: Unaffected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
opc  
dst | src  
src  
2
4
6
42  
43  
r
r
r
lr  
dst  
3
3
6
6
44  
45  
R
R
R
IR  
opc  
dst  
src  
=
6
46  
R
IM  
Examples:  
Given: R0  
=
15H, R1  
2AH, R2  
=
01H, register 00H  
=
08H, register 01H  
=
37H, and register 08H  
=
8AH:  
OR  
OR  
OR  
OR  
OR  
R0,R1  
R0  
R0  
=
=
3FH, R1  
37H, R2  
=
=
2AH  
01H, register 01H  
R0,@R2  
00H,01H  
01H,@00H  
00H,#02H  
=
37H  
Register 00H  
Register 00H  
Register 00H  
=
=
=
3FH, register 01H  
08H, register 01H  
0AH  
=
=
37H  
0BFH  
In the first example, if working register R0 contains the value 15H and register R1 the value 2AH,  
the statement "OR R0,R1" logical-ORs the R0 and R1 register contents and stores the result  
(3FH) in destination register R0.  
The other examples show the use of the logical OR instruction with the various addressing  
modes and formats.  
6-62  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
POP— Pop From Stack  
POP  
dst  
Operation:  
dst  
SP  
@SP  
SP  
+
1
The contents of the location addressed by the stack pointer are loaded into the destination. The  
stack pointer is then incremented by one.  
Flags:  
No flags affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
opc  
dst  
2
8
8
50  
51  
R
IR  
Examples:  
Given: Register 00H  
0FBH, and stack register 0FBH  
=
01H, register 01H  
55H:  
=
1BH, SPH (0D8H)  
=
00H, SPL (0D9H)  
=
=
POP  
POP  
00H  
Register 00H  
Register 00H  
=
55H, SP  
=
00FCH  
@00H  
=
01H, register 01H  
=
55H, SP  
=
00FCH  
In the first example, general register 00H contains the value 01H. The statement "POP 00H"  
loads the contents of location 00FBH (55H) into destination register 00H and then increments the  
stack pointer by one. Register 00H then contains the value 55H and the SP points to location  
00FCH.  
6-63  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
POPUD— Pop User Stack (Decrementing)  
POPUD  
dst,src  
Operation:  
dst  
IR  
src  
IR – 1  
This instruction is used for user-defined stacks in the register file. The contents of the register file  
location addressed by the user stack pointer are loaded into the destination. The user stack  
pointer is then decremented.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
src  
dst  
3
8
92  
R
IR  
Example:  
Given: Register 00H  
register 02H 70H:  
=
42H (user stack pointer register), register 42H  
=
6FH, and  
=
POPUD 02H,@00H  
Register 00H  
=
41H, register 02H = 6FH, register 42H = 6FH  
If general register 00H contains the value 42H and register 42H the value 6FH, the statement  
"POPUD 02H,@00H" loads the contents of register 42H into the destination register 02H. The  
user stack pointer is then decremented by one, leaving the value 41H.  
6-64  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
POPUI— Pop User Stack (Incrementing)  
POPUI  
dst,src  
Operation:  
dst  
IR  
src  
IR + 1  
The POPUI instruction is used for user-defined stacks in the register file. The contents of the  
register file location addressed by the user stack pointer are loaded into the destination. The user  
stack pointer is then incremented.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
src  
dst  
3
8
93  
R
IR  
Example:  
Given: Register 00H  
POPUI 02H,@00H  
=
01H and register 01H  
=
70H:  
Register 00H = 02H, register 01H = 70H, register 02H = 70H  
If general register 00H contains the value 01H and register 01H the value 70H, the statement  
"POPUI 02H,@00H" loads the value 70H into the destination general register 02H. The user  
stack pointer (register 00H) is then incremented by one, changing its value from 01H to 02H.  
6-65  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
PUSH— Push To Stack  
PUSH  
src  
Operation:  
SP  
SP  
1
@SP  
src  
A PUSH instruction decrements the stack pointer value and loads the contents of the source (src)  
into the location addressed by the decremented stack pointer. The operation then adds the new  
value to the top of the stack.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
opc  
src  
2
8 (internal clock)  
8 (external clock)  
70  
R
8 (internal clock)  
8 (external clock)  
71  
IR  
Examples:  
Given: Register 40H  
=
4FH, register 4FH  
Register 40H  
=
0AAH, SPH  
=
00H, and SPL  
=
00H:  
PUSH  
40H  
=
4FH, stack register 0FFH  
=
4FH,  
SPH  
=
0FFH, SPL 0FFH  
=
PUSH  
@40H  
Register 40H  
=
4FH, register 4FH  
=
0AAH, stack register  
= 0FFH  
0FFH 0AAH, SPH  
=
=
0FFH, SPL  
In the first example, if the stack pointer contains the value 0000H, and general register 40H the  
value 4FH, the statement "PUSH 40H" decrements the stack pointer from 0000 to 0FFFFH. It  
then loads the contents of register 40H into location 0FFFFH and adds this new value to the top  
of the stack.  
6-66  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
PUSHUD— Push User Stack (Decrementing)  
PUSHUD  
dst,src  
Operation:  
IR  
IR – 1  
dst  
src  
This instruction is used to address user-defined stacks in the register file. PUSHUD decrements  
the user stack pointer and loads the contents of the source into the register addressed by the  
decremented stack pointer.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
dst  
src  
3
8
82  
IR  
R
Example:  
Given: Register 00H  
PUSHUD @00H,01H  
=
03H, register 01H  
=
05H, and register 02H  
=
1AH:  
Register 00H = 02H, register 01H = 05H, register 02H = 05H  
If the user stack pointer (register 00H, for example) contains the value 03H, the statement  
"PUSHUD @00H,01H" decrements the user stack pointer by one, leaving the value 02H. The  
01H register value, 05H, is then loaded into the register addressed by the decremented user  
stack pointer.  
6-67  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
PUSHUI— Push User Stack (Incrementing)  
PUSHUI  
dst,src  
Operation:  
IR  
IR  
src  
+
1
dst  
This instruction is used for user-defined stacks in the register file. PUSHUI increments the user  
stack pointer and then loads the contents of the source into the register location addressed by  
the incremented user stack pointer.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
dst  
src  
3
8
83  
IR  
R
Example:  
Given: Register 00H  
PUSHUI @00H,01H  
=
03H, register 01H  
=
05H, and register 04H  
=
2AH:  
Register 00H = 04H, register 01H = 05H, register 04H = 05H  
If the user stack pointer (register 00H, for example) contains the value 03H, the statement  
"PUSHUI @00H,01H" increments the user stack pointer by one, leaving the value 04H. The 01H  
register value, 05H, is then loaded into the location addressed by the incremented user stack  
pointer.  
6-68  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
RCF— Reset Carry Flag  
RCF  
RCF  
Operation:  
C
0
The carry flag is cleared to logic zero, regardless of its previous value.  
Flags:  
C: Cleared to "0".  
No other flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
opc  
1
4
CF  
Example:  
Given: C = "1" or "0":  
The instruction RCF clears the carry flag (C) to logic zero.  
6-69  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
RET— Return  
RET  
Operation:  
PC  
SP  
@SP  
SP  
+
2
The RET instruction is normally used to return to the previously executing procedure at the end of  
a procedure entered by a CALL instruction. The contents of the location addressed by the stack  
pointer are popped into the program counter. The next statement that is executed is the one that  
is addressed by the new program counter value.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode (Hex)  
opc  
1
8 (internal stack)  
10 (internal stack)  
AF  
Example:  
Given: SP  
=
00FCH, (SP)  
PC  
=
101AH, and PC  
=
1234:  
RET  
=
101AH, SP  
=
00FEH  
The statement "RET" pops the contents of stack pointer location 00FCH (10H) into the high byte  
of the program counter. The stack pointer then pops the value in location 00FEH (1AH) into the  
PC's low byte and the instruction at location 101AH is executed. The stack pointer now points to  
memory location 00FEH.  
6-70  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
RL— Rotate Left  
RL  
dst  
Operation:  
C
dst (7)  
dst (0) dst (7)  
dst (n 1)  
+
dst (n),  
n
=
0–6  
The contents of the destination operand are rotated left one bit position. The initial value of bit 7 is  
moved to the bit zero (LSB) position and also replaces the carry flag.  
7
0
C
Flags:  
C: Set if the bit rotated from the most significant bit position (bit 7) was "1".  
Z: Set if the result is "0"; cleared otherwise.  
S: Set if the result bit 7 is set; cleared otherwise.  
V: Set if arithmetic overflow occurred; cleared otherwise.  
D: Unaffected.  
H: Unaffected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
opc  
dst  
2
4
4
90  
91  
R
IR  
Examples:  
Given: Register 00H  
=
0AAH, register 01H  
=
02H and register 02H  
=
17H:  
RL  
RL  
00H  
Register 00H  
Register 01H  
=
55H, C  
=
"1"  
@01H  
=
02H, register 02H  
=
2EH, C  
=
"0"  
In the first example, if general register 00H contains the value 0AAH (10101010B), the statement  
"RL 00H" rotates the 0AAH value left one bit position, leaving the new value 55H (01010101B)  
and setting the carry and overflow flags.  
6-71  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
RLC— Rotate Left Through Carry  
RLC  
dst  
Operation:  
dst (0) ←  
C
C
dst (7)  
1) dst (n), n  
dst (n  
+
=
0–6  
The contents of the destination operand with the carry flag are rotated left one bit position. The  
initial value of bit 7 replaces the carry flag (C); the initial value of the carry flag replaces bit zero.  
7
0
C
Flags:  
C: Set if the bit rotated from the most significant bit position (bit 7) was "1".  
Z: Set if the result is "0"; cleared otherwise.  
S: Set if the result bit 7 is set; cleared otherwise.  
V: Set if arithmetic overflow occurred, that is, if the sign of the destination changed during  
rotation; cleared otherwise.  
D: Unaffected.  
H: Unaffected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
opc  
dst  
2
4
4
10  
11  
R
IR  
Examples:  
Given: Register 00H  
=
0AAH, register 01H  
=
02H, and register 02H  
=
17H, C  
=
"0":  
RLC  
RLC  
00H  
Register 00H  
Register 01H  
=
54H, C  
=
"1"  
@01H  
=
02H, register 02H  
=
2EH, C = "0"  
In the first example, if general register 00H has the value 0AAH (10101010B), the statement  
"RLC 00H" rotates 0AAH one bit position to the left. The initial value of bit 7 sets the carry flag  
and the initial value of the C flag replaces bit zero of register 00H, leaving the value 55H  
(01010101B). The MSB of register 00H resets the carry flag to "1" and sets the overflow flag.  
6-72  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
RR— Rotate Right  
RR  
dst  
Operation:  
C
dst (0)  
dst (0)  
dst (n) ← dst (n  
dst (7)  
+
1), n  
=
0–6  
The contents of the destination operand are rotated right one bit position. The initial value of bit  
zero (LSB) is moved to bit 7 (MSB) and also replaces the carry flag (C).  
7
0
C
Flags:  
C: Set if the bit rotated from the least significant bit position (bit zero) was "1".  
Z: Set if the result is "0"; cleared otherwise.  
S: Set if the result bit 7 is set; cleared otherwise.  
V: Set if arithmetic overflow occurred, that is, if the sign of the destination changed during  
rotation; cleared otherwise.  
D: Unaffected.  
H: Unaffected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
opc  
dst  
2
4
4
E0  
E1  
R
IR  
Examples:  
Given: Register 00H  
=
31H, register 01H  
=
02H, and register 02H  
=
17H:  
RR  
RR  
00H  
Register 00H  
Register 01H  
=
98H, C  
=
"1"  
@01H  
=
02H, register 02H  
=
8BH, C  
=
"1"  
In the first example, if general register 00H contains the value 31H (00110001B), the statement  
"RR 00H" rotates this value one bit position to the right. The initial value of bit zero is moved to  
bit 7, leaving the new value 98H (10011000B) in the destination register. The initial bit zero also  
resets the C flag to "1" and the sign flag and overflow flag are also set to "1".  
6-73  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
RRC— Rotate Right Through Carry  
RRC  
dst  
Operation:  
dst (7)  
C
C
dst (0)  
dst (n  
dst (n)  
+
1), n  
=
0–6  
The contents of the destination operand and the carry flag are rotated right one bit position. The  
initial value of bit zero (LSB) replaces the carry flag; the initial value of the carry flag replaces bit 7  
(MSB).  
7
0
C
Flags:  
C: Set if the bit rotated from the least significant bit position (bit zero) was "1".  
Z: Set if the result is "0" cleared otherwise.  
S: Set if the result bit 7 is set; cleared otherwise.  
V: Set if arithmetic overflow occurred, that is, if the sign of the destination changed during  
rotation; cleared otherwise.  
D: Unaffected.  
H: Unaffected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
opc  
dst  
2
4
4
C0  
C1  
R
IR  
Examples:  
Given: Register 00H  
=
55H, register 01H  
=
02H, register 02H  
=
17H, and C  
=
"0":  
RRC  
RRC  
00H  
Register 00H  
Register 01H  
=
2AH, C  
=
"1"  
@01H  
=
02H, register 02H  
=
0BH, C  
=
"1"  
In the first example, if general register 00H contains the value 55H (01010101B), the statement  
"RRC 00H" rotates this value one bit position to the right. The initial value of bit zero ("1")  
replaces the carry flag and the initial value of the C flag ("1") replaces bit 7. This leaves the new  
value 2AH (00101010B) in destination register 00H. The sign flag and overflow flag are both  
cleared to "0".  
6-74  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
SB0— Select Bank 0  
SB0  
Operation:  
BANK ←  
0
The SB0 instruction clears the bank address flag in the FLAGS register (FLAGS.0) to logic zero,  
selecting bank 0 register addressing in the set 1 area of the register file.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
opc  
1
4
4F  
Example:  
The statement  
SB0  
clears FLAGS.0 to "0", selecting bank 0 register addressing.  
6-75  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
SB1— Select Bank 1  
SB1  
Operation:  
BANK 1  
The SB1 instruction sets the bank address flag in the FLAGS register (FLAGS.0) to logic one,  
selecting bank 1 register addressing in the set 1 area of the register file. (Bank 1 is not  
implemented in some S3C8-series microcontrollers.)  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
opc  
1
4
5F  
Example:  
The statement  
SB1  
sets FLAGS.0 to "1", selecting bank 1 register addressing, if implemented.  
6-76  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
SBC— Subtract with Carry  
SBC  
dst,src  
Operation:  
dst  
dst  
src  
c
The source operand, along with the current value of the carry flag, is subtracted from the  
destination operand and the result is stored in the destination. The contents of the source are  
unaffected. Subtraction is performed by adding the two's-complement of the source operand to  
the destination operand. In multiple precision arithmetic, this instruction permits the carry  
("borrow") from the subtraction of the low-order operands to be subtracted from the subtraction of  
high-order operands.  
Flags:  
C: Set if a borrow occurred (src  
>
dst); cleared otherwise.  
Z: Set if the result is "0"; cleared otherwise.  
S: Set if the result is negative; cleared otherwise.  
V: Set if arithmetic overflow occurred, that is, if the operands were of opposite sign and the sign  
of the result is the same as the sign of the source; cleared otherwise.  
D: Always set to "1".  
H: Cleared if there is a carry from the most significant bit of the low-order four bits of the result;  
set otherwise, indicating a "borrow".  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
opc  
dst | src  
src  
2
4
6
32  
33  
r
r
r
lr  
dst  
3
3
6
6
34  
35  
R
R
R
IR  
opc  
dst  
src  
=
6
36  
R
=
IM  
Examples:  
Given: R1  
=
10H, R2  
03H, C  
=
"1", register 01H  
=
20H, register 02H  
03H,  
and register 03H  
=
0AH:  
SBC  
SBC  
SBC  
R1,R2  
R1  
R1  
=
0CH, R2  
05H, R2  
=
03H  
03H, register 03H  
R1,@R2  
=
=
=
0AH  
01H,02H  
01H,@02H  
Register 01H  
Register 01H  
=
=
1CH, register 02H  
15H,register 02H  
=
03H  
SBC  
0AH  
=
03H, register 03H  
"1"  
=
SBC  
01H,#8AH  
Register 01H  
=
95H; C, S, and V  
=
In the first example, if working register R1 contains the value 10H and register R2 the value 03H,  
the statement "SBC R1,R2" subtracts the source value (03H) and the C flag value ("1") from the  
destination (10H) and then stores the result (0CH) in register R1.  
6-77  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
SCF— Set Carry Flag  
SCF  
Operation:  
Flags:  
C ←  
1
The carry flag (C) is set to logic one, regardless of its previous value.  
C: Set to "1".  
No other flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
opc  
1
4
DF  
Example:  
The statement  
SCF  
sets the carry flag to logic one.  
6-78  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
SRA— Shift Right Arithmetic  
SRA  
dst  
Operation:  
dst (7)  
dst (7)  
dst (0)  
dst (n  
C
dst (n)  
+
1), n  
=
0–6  
An arithmetic shift-right of one bit position is performed on the destination operand. Bit zero (the  
LSB) replaces the carry flag. The value of bit 7 (the sign bit) is unchanged and is shifted into bit  
position 6.  
7
6
0
C
Flags:  
C: Set if the bit shifted from the LSB position (bit zero) was "1".  
Z: Set if the result is "0"; cleared otherwise.  
S: Set if the result is negative; cleared otherwise.  
V: Always cleared to "0".  
D: Unaffected.  
H: Unaffected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
opc  
dst  
2
4
4
D0  
D1  
R
IR  
Examples:  
Given: Register 00H  
=
9AH, register 02H  
=
03H, register 03H  
=
0BCH, and C  
=
"1":  
SRA  
SRA  
00H  
Register 00H  
Register 02H  
=
0CD, C  
=
"0"  
@02H  
=
03H, register 03H  
=
0DEH, C  
=
"0"  
In the first example, if general register 00H contains the value 9AH (10011010B), the statement  
"SRA 00H" shifts the bit values in register 00H right one bit position. Bit zero ("0") clears the C  
flag and bit 7 ("1") is then shifted into the bit 6 position (bit 7 remains unchanged). This leaves the  
value 0CDH (11001101B) in destination register 00H.  
6-79  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
SRP/SRP0/SRP1— Set Register Pointer  
SRP  
src  
src  
src  
SRP0  
SRP1  
Operation:  
If src (1)  
If src (1)  
If src (1)  
=
=
=
1 and src (0)  
0 and src (0)  
0 and src (0)  
=
=
=
0 then:  
1 then:  
0 then:  
RP0 (3–7)  
RP1 (3–7)  
RP0 (4–7)  
RP0 (3)  
src (3–7)  
src (3–7)  
src (4–7),  
0
RP1 (4–7)  
RP1 (3)  
src (4–7),  
1
The source data bits one and zero (LSB) determine whether to write one or both of the register  
pointers, RP0 and RP1. Bits 3–7 of the selected register pointer are written unless both register  
pointers are selected. RP0.3 is then cleared to logic zero and RP1.3 is set to logic one.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
src  
opc  
src  
2
4
31  
IM  
Examples:  
The statement  
SRP #40H  
sets register pointer 0 (RP0) at location 0D6H to 40H and register pointer 1 (RP1) at location  
0D7H to 48H.  
The statement "SRP0 #50H" sets RP0 to 50H, and the statement "SRP1 #68H" sets RP1 to  
68H.  
6-80  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
STOP— Stop Operation  
STOP  
Operation:  
The STOP instruction stops the both the CPU clock and system clock and causes the  
microcontroller to enter Stop mode. During Stop mode, the contents of on-chip CPU registers,  
peripheral registers, and I/O port control and data registers are retained. Stop mode can be  
released by an external reset operation or by external interrupts. For the reset operation, the  
RESET pin must be held to Low level until the required oscillation stabilization interval has  
elapsed.  
In application programs, a STOP instruction must be immediately followed by at least three NOP  
instructions. This ensures an adeguate time interval for the clock to stabilize before the next  
instruction is executed. If three or more NOP instructons are not used after STOP instruction,  
leakage current could be flown because of the floating state in the internal bus.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
1
4
7F  
Example:  
The statement  
STOP  
NOP  
NOP  
NOP  
;
halts all microcontroller operations  
6-81  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
SUB— Subtract  
SUB  
dst,src  
Operation:  
dst  
dst – src  
The source operand is subtracted from the destination operand and the result is stored in the  
destination. The contents of the source are unaffected. Subtraction is performed by adding the  
two's complement of the source operand to the destination operand.  
Flags:  
C: Set if a "borrow" occurred; cleared otherwise.  
Z: Set if the result is "0"; cleared otherwise.  
S: Set if the result is negative; cleared otherwise.  
V: Set if arithmetic overflow occurred, that is, if the operands were of opposite signs and the  
sign of the result is of the same as the sign of the source operand; cleared otherwise.  
D: Always set to "1".  
H: Cleared if there is a carry from the most significant bit of the low-order four bits of the result;  
set otherwise indicating a "borrow".  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
opc  
dst | src  
src  
2
4
6
22  
23  
r
r
r
lr  
dst  
3
6
6
24  
25  
R
R
R
IR  
opc  
dst  
src  
=
3
=
6
26  
R
IM  
Examples:  
Given: R1  
=
12H, R2  
03H, register 01H  
21H, register 02H  
=
03H, register 03H  
=
0AH:  
SUB  
SUB  
SUB  
SUB  
SUB  
SUB  
R1,R2  
R1  
R1  
=
=
0FH, R2  
08H, R2  
=
=
03H  
03H  
R1,@R2  
01H,02H  
01H,@02H  
01H,#90H  
01H,#65H  
Register 01H  
Register 01H  
Register 01H  
Register 01H  
=
=
=
=
1EH, register 02H  
17H, register 02H  
91H; C, S, and V  
=
03H  
03H  
"1"  
"1", V  
=
=
0BCH; C and S  
=
=
"0"  
In the first example, if working register R1 contains the value 12H and if register R2 contains the  
value 03H, the statement "SUB R1,R2" subtracts the source value (03H) from the destination  
value (12H) and stores the result (0FH) in destination register R1.  
6-82  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
SWAP— Swap Nibbles  
SWAP  
dst  
Operation:  
dst (0  
3)  
dst (4 – 7)  
The contents of the lower four bits and upper four bits of the destination operand are swapped.  
7
4 3  
0
Flags:  
C: Undefined.  
Z: Set if the result is "0"; cleared otherwise.  
S: Set if the result bit 7 is set; cleared otherwise.  
V: Undefined.  
D: Unaffected.  
H: Unaffected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
opc  
dst  
2
4
4
F0  
F1  
R
IR  
Examples:  
Given: Register 00H  
=
3EH, register 02H  
=
03H, and register 03H  
=
0A4H:  
SWAP  
SWAP  
00H  
Register 00H  
Register 02H  
= 0E3H  
@02H  
=
03H, register 03H  
=
4AH  
In the first example, if general register 00H contains the value 3EH (00111110B), the statement  
"SWAP 00H" swaps the lower and upper four bits (nibbles) in the 00H register, leaving the  
value 0E3H (11100011B).  
6-83  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
TCM— Test Complement Under Mask  
TCM  
dst,src  
Operation:  
(NOT dst) AND src  
This instruction tests selected bits in the destination operand for a logic one value. The bits to be  
tested are specified by setting a "1" bit in the corresponding position of the source operand  
(mask). The TCM statement complements the destination operand, which is then ANDed with the  
source mask. The zero (Z) flag can then be checked to determine the result. The destination and  
source operands are unaffected.  
Flags:  
C: Unaffected.  
Z: Set if the result is "0"; cleared otherwise.  
S: Set if the result bit 7 is set; cleared otherwise.  
V: Always cleared to "0".  
D: Unaffected.  
H: Unaffected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
opc  
dst | src  
src  
2
4
6
62  
63  
r
r
r
lr  
dst  
src  
3
3
6
6
64  
65  
R
R
R
IR  
opc  
dst  
6
66  
R
IM  
Examples:  
Given: R0  
=
0C7H, R1  
=
02H, R2  
=
12H, register 00H  
=
2BH, register 01H  
=
02H, and register 02H  
=
23H:  
TCM  
TCM  
TCM  
TCM  
R0,R1  
R0  
R0  
=
=
0C7H, R1  
0C7H, R1  
=
=
02H, Z  
=
"1"  
R0,@R1  
00H,01H  
00H,@01H  
02H, register 02H  
=
23H, Z  
=
"0"  
Register 00H  
=
=
2BH, register 01H  
2BH, register 01H  
=
=
02H, Z  
02H,  
=
"1"  
Register 00H  
register 02H  
=
23H, Z  
=
"1"  
TCM  
00H,#34  
Register 00H  
=
2BH, Z  
=
"0"  
In the first example, if working register R0 contains the value 0C7H (11000111B) and register R1  
the value 02H (00000010B), the statement "TCM R0,R1" tests bit one in the destination register  
for a "1" value. Because the mask value corresponds to the test bit, the Z flag is set to logic one  
and can be tested to determine the result of the TCM operation.  
6-84  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
TM— Test Under Mask  
TM  
dst,src  
Operation:  
dst AND src  
This instruction tests selected bits in the destination operand for a logic zero value. The bits to be  
tested are specified by setting a "1" bit in the corresponding position of the source operand  
(mask), which is ANDed with the destination operand. The zero (Z) flag can then be checked to  
determine the result. The destination and source operands are unaffected.  
Flags:  
C: Unaffected.  
Z: Set if the result is "0"; cleared otherwise.  
S: Set if the result bit 7 is set; cleared otherwise.  
V: Always reset to "0".  
D: Unaffected.  
H: Unaffected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
opc  
dst | src  
src  
2
4
6
72  
73  
r
r
r
lr  
dst  
src  
3
3
6
6
74  
75  
R
R
R
IR  
opc  
dst  
6
76  
R
IM  
Examples:  
Given: R0  
=
0C7H, R1  
=
02H, R2  
=
18H, register 00H  
=
2BH, register 01H  
=
02H, and register 02H  
=
23H:  
TM  
TM  
TM  
TM  
R0,R1  
R0  
R0  
=
=
0C7H, R1  
0C7H, R1  
=
=
02H, Z  
=
"0"  
R0,@R1  
00H,01H  
00H,@01H  
02H, register 02H  
=
23H, Z  
02H, Z  
2BH, register 01H = 02H,  
=
"0"  
Register 00H  
=
=
2BH, register 01H  
=
=
"0"  
Register 00H  
register 02H  
=
23H, Z  
=
"0"  
TM  
00H,#54H  
Register 00H  
=
2BH, Z  
=
"1"  
In the first example, if working register R0 contains the value 0C7H (11000111B) and register R1  
the value 02H (00000010B), the statement "TM R0,R1" tests bit one in the destination register  
for a "0" value. Because the mask value does not match the test bit, the Z flag is cleared to logic  
zero and can be tested to determine the result of the TM operation.  
6-85  
INSTRUCTION SET  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
WFI— Wait for Interrupt  
WFI  
Operation:  
The CPU is effectively halted until an interrupt occurs, except that DMA transfers can still take  
place during this wait state. The WFI status can be released by an internal interrupt, including a  
fast interrupt.  
Flags:  
No flags are affected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
opc  
1
4n  
3F  
( n  
=
1, 2, 3, … )  
Example:  
The following sample program structure shows the sequence of operations that follow a "WFI"  
statement:  
Main program  
.
.
.
EI  
WFI  
(Enable global interrupt)  
(Wait for interrupt)  
(Next instruction)  
.
.
.
Interrupt occurs  
Interrupt service routine  
.
.
.
Clear interrupt flag  
IRET  
Service routine completed  
6-86  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
INSTRUCTION SET  
XOR— Logical Exclusive OR  
XOR  
dst,src  
Operation:  
dst  
dst XOR src  
The source operand is logically exclusive-ORed with the destination operand and the result is  
stored in the destination. The exclusive-OR operation results in a "1" bit being stored whenever  
the corresponding bits in the operands are different; otherwise, a "0" bit is stored.  
Flags:  
C: Unaffected.  
Z: Set if the result is "0"; cleared otherwise.  
S: Set if the result bit 7 is set; cleared otherwise.  
V: Always reset to "0".  
D: Unaffected.  
H: Unaffected.  
Format:  
Bytes  
Cycles  
Opcode  
(Hex)  
Addr Mode  
dst  
src  
opc  
opc  
dst | src  
src  
2
4
6
B2  
B3  
r
r
r
lr  
dst  
src  
3
3
6
6
B4  
B5  
R
R
R
IR  
opc  
dst  
6
B6  
R
IM  
Examples:  
Given: R0  
=
0C7H, R1  
=
02H, R2  
=
18H, register 00H  
=
2BH, register 01H  
=
02H, and register 02H  
=
23H:  
XOR  
XOR  
XOR  
XOR  
XOR  
R0,R1  
R0  
R0  
=
=
0C5H, R1  
0E4H, R1  
=
=
02H  
02H, register 02H = 23H  
R0,@R1  
00H,01H  
00H,@01H  
00H,#54H  
Register 00H  
Register 00H  
Register 00H  
=
=
=
29H, register 01H = 02H  
08H, register 01H = 02H, register 02H = 23H  
7FH  
In the first example, if working register R0 contains the value 0C7H and if register R1 contains  
the value 02H, the statement "XOR R0,R1" logically exclusive-ORs the R1 value with the R0  
value and stores the result (0C5H) in the destination register R0.  
6-87  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CLOCK CIRCUIT  
7
CLOCK CIRCUIT  
OVERVIEW  
The S3C8275X/C8278X/C8274X microcontroller has two oscillator circuits: a main clock and a sub clock circuit.  
The CPU and peripheral hardware operate on the system clock frequency supplied through these circuits. The  
maximum CPU clock frequency of S3C8275X/C8278X/C8274X is determined by CLKCON register settings.  
SYSTEM CLOCK CIRCUIT  
The system clock circuit has the following components:  
External crystal, ceramic resonator, RC oscillation source, or an external clock source  
Oscillator stop and wake-up functions  
Programmable frequency divider for the CPU clock (fxx divided by 1, 2, 8, or 16)  
System clock control register, CLKCON  
Oscillator control register, OSCCON and STOP control register, STPCON  
Clock output control register, CLOCON  
CPU Clock Notation  
In this document, the following notation is used for descriptions of the CPU clock;  
fx: main clock  
fxt: sub clock  
fxx: selected system clock  
7-1  
CLOCK CIRCUIT  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
SUB OSCILLATOR CIRCUITS  
MAIN OSCILLATOR CIRCUITS  
32.768 kHz  
XTIN  
XIN  
XTOUT  
XOUT  
V
REG  
104  
Figure 7-1. Crystal/Ceramic Oscillator (fx)  
Figure 7-4. Crystal Oscillator (fxt)  
XTIN  
XIN  
XTOUT  
XOUT  
Figure 7-5. External Oscillator (fxt)  
Figure 7-2. External Oscillator (fx)  
XIN  
R
XOUT  
Figure 7-3. RC Oscillator (fx)  
7-2  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CLOCK CIRCUIT  
CLOCK STATUS DURING POWER-DOWN MODES  
The two power-down modes, Stop mode and Idle mode, affect the system clock as follows:  
In stop mode, the main oscillator is halted. Stop mode is released, and the oscillator started, by a reset  
operation or an external interrupt (with RC delay noise filter).  
In Idle mode, the internal clock signal is gated to the CPU, but not to interrupt structure, timers and timer/  
counters. Idle mode is released by a reset or by an external or internal interrupt.  
Stop Release  
INT  
Main-System  
Oscillator  
Circuit  
Sub-system  
Oscillator  
Circuit  
fx  
fxt  
Watch Timer  
LCD Controller  
Selector 1  
fXX  
Stop  
OSCCON.3  
OSCCON.0  
Stop  
OSCCON.2  
1/1-1/4096  
STOP OSC  
inst.  
Basic Timer  
Timer/Counters  
STPCON  
Watch Timer  
LCD Controller  
SIO  
Frequency  
Dividing  
Circuit  
BLD  
1/1 1/2 1/8 1/16  
Selector 2  
System Clock  
CLKCON.4-.3  
CPU Clock  
IDLE Instruction  
Figure 7-6. System Clock Circuit Diagram  
7-3  
CLOCK CIRCUIT  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
SYSTEM CLOCK CONTROL REGISTER (CLKCON)  
The system clock control register, CLKCON, is located in the set 1, at address D4H. It is read/write addressable  
and has the following functions:  
Oscillator IRQ wake up function enable/disable  
Oscillator frequency divide-by value  
CLKCON register settings control whether or not an external interrupt can be used to trigger a stop mode release  
(This is called the "IRQ wake-up" function). The IRQ "wake-up" enable bit is CLKCON.7.  
After the main oscillator is activated, and the fxx/16 (the slowest clock speed) is selected as the CPU clock. If  
necessary, you can then increase the CPU clock speed to fxx/8, fxx/2, or fxx/1.  
System Clock Control Register (CLKCON)  
D4H, Set 1, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
Oscillator IRQ wake-up function bit:  
0 = Enable IRQ for main wake up in  
power down mode  
Not used for S3C8275X/C8278X/C8274X  
(must keep always 0)  
1 = Disable IRQ for main wake up in  
power down mode  
Divide-by selection bits for  
CPU clock frequency:  
00 = fxx/16  
01 = fxx/8  
10 = fxx/2  
Not used for S3C8275X/C8278X/C8274X  
(must keep always 0)  
11 = fxx/1 (non-divided)  
Figure 7-7. System Clock Control Register (CLKCON)  
7-4  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
CLOCK CIRCUIT  
CLOCK OUTPUT CONTROL REGISTER (CLOCON)  
The clock output control register, CLOCON, is located in set 1 bank 1, at address E8H. It is read/write  
addressable and has the following functions:  
Clock output frequency selection  
After a reset, fxx/64 is select for clock output frequency because the reset value of CLOCON.1.0 is "00b".  
Clock Output Control Register (CLOCON)  
E8H, Set 1, Bank 1, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
Not used for S3C8275X/C8278X/C8274X  
(must keep always "0")  
Clock output frequency selection bits:  
00 = Select fxx/64  
01 = Select fxx/16  
10 = Select fxx/8  
11 = Select fxx/4  
Figure 7-8. Clock Output Control Register (CLOCON)  
CLOCON.1-.0  
P0CONH.5-.4  
fxx/64  
fxx/16  
fxx/8  
CLKOUT/P0.6  
MUX  
fxx/4  
Figure 7-9. Clock Output Block Diagram  
7-5  
CLOCK CIRCUIT  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
OSCILLATOR CONTROL REGISTER (OSCCON)  
The oscillator control register, OSCCON, is located in set 1, bank 0, at address E0H. It is read/write addressable  
and has the following functions:  
System clock selection  
Main oscillator control  
Sub oscillator control  
Sub oscillator circuit selection  
OSCCON.0 register settings select Main clock or Sub clock as system clock.  
After a reset, Main clock is selected for system clock because the reset value of OSCCON.0 is "0".  
The main oscillator can be stopped or run by setting OSCCON.3.  
The sub oscillator can be stopped or run by setting OSCCON.2.  
Oscillator Control Register (OSCCON)  
E0H, Set 1, Bank 0, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
System clock selection bit:  
0 = Main oscillator select  
1 = Sub oscillator select  
Not used for S3C8275X/  
C8278X/C8274X  
Sub oscillator circuit selection bit:  
0 = Initial state  
Not used for S3C8275X/C8278X/C8274X  
1 = Power saving circuit for sub oscillator  
(Automatically cleared to "0" when the sub  
oscillator is stopped by OSCCON.2)  
Sub oscillator control bit:  
0 = Sub oscillator RUN  
1 = Sub oscillator STOP  
NOTES:  
1. The OSCCON.7 must be maintained to "1", during  
the suboscillator operation.  
2. A capacitor (0.1uF) should be connected between  
VREG and GND.  
Main oscillator control bit:  
0 = Main oscillator RUN  
1 = Main oscillator STOP  
Figure 7-10. Oscillator Control Register (OSCCON)  
7-6  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
SWITCHING THE CPU CLOCK  
CLOCK CIRCUIT  
Data loading in the oscillator control register, OSCCON, determine whether a main or a sub clock is selected as  
the CPU clock, and also how this frequency is to be divided by setting CLKCON. This makes it possible to switch  
dynamically between main and sub clocks and to modify operating frequencies.  
OSCCON.0 select the main clock (fx) or the sub clock (fxt) for the CPU clock. OSCCON.3 start or stop main clock  
oscillation, and OSCCON.2 start or stop sub clock oscillation. CLKCON.4.3 control the frequency divider circuit,  
and divide the selected fxx clock by 1, 2, 8, 16.  
For example, you are using the default CPU clock (normal operating mode and a main clock of fx/16) and you  
want to switch from the fx clock to a sub clock and to stop the main clock. To do this, you need to set CLKCON.4-  
.3 to "11", OSCCON.0 to “1”, and OSCCON.3 to “1” simultaneously. This switches the clock from fx to fxt and  
stops main clock oscillation.  
The following steps must be taken to switch from a sub clock to the main clock: first, set OSCCON.3 to “0” to  
enable main clock oscillation. Then, after a certain number of machine cycles has elapsed, select the main clock  
by setting OSCCON.0 to “0”.  
)
PROGRAMMING TIP Switching the CPU clock  
1. This example shows how to change from the main clock to the sub clock:  
MA2SUB LD  
OSCCON,#01H  
; Switches to the sub clock  
; Stop the main clock oscillation  
RET  
2. This example shows how to change from sub clock to main clock:  
SUB2MA AND  
OSCCON,#07H  
DLY16  
OSCCON,#06H  
; Start the main clock oscillation  
; Delay 16 ms  
; Switch to the main clock  
CALL  
AND  
RET  
DLY16  
DEL  
SRP  
LD  
NOP  
DJNZ  
RET  
#0C0H  
R0,#20H  
R0,DEL  
7-7  
CLOCK CIRCUIT  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
STOP Control Register (STPCON)  
FBH, Set 1, Bank 0, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
STOP control bits:  
Other values = Disable STOP instruction  
10100101 = Enable STOP instruction  
NOTE:  
Before execute the STOP instruction, set this STPCON register as "10100101B".  
Otherwise the STOP instuction will not execute as well as reset will be generated.  
Figure 7-11. STOP Control Register (STPCON)  
7-8  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
RESET and POWER-DOWN  
8
RESET and POWER-DOWN  
SYSTEM RESET  
OVERVIEW  
During a power-on reset, the voltage at VDD goes to High level and the nRESET pin is forced to Low level. The  
nRESET signal is input through a schmitt trigger circuit where it is then synchronized with the CPU clock. This  
procedure brings the S3C8275X/C8278X/C8274X into a known operating status.  
To allow time for internal CPU clock oscillation to stabilize, the nRESET pin must be held to Low level for a  
minimum time interval after the power supply comes within tolerance. The minimum required time of a reset  
operation for oscillation stabilization is 1 millisecond.  
Whenever a reset occurs during normal operation (that is, when both VDD and nRESET are High level), the  
nRESET pin is forced Low level and the reset operation starts. All system and peripheral control registers are  
then reset to their default hardware values  
In summary, the following sequence of events occurs during a reset operation:  
All interrupt is disabled.  
The watchdog function (basic timer) is enabled.  
Ports 0-6 are set to input mode, and all pull-up resistors are disabled for the I/O port.  
Peripheral control and data register settings are disabled and reset to their default hardware values.  
The program counter (PC) is loaded with the program reset address in the ROM, 0100H.  
When the programmed oscillation stabilization time interval has elapsed, the instruction stored in ROM  
location 0100H (and 0101H) is fetched and executed at normal mode by smart option.  
The reset address of ROM can be changed by a smart option only in the S3F8275X (Full-Flash Device).  
Refer to the chapter 16. Embedded Flash Memory Interface for more detail contents.  
NORMAL MODE RESET OPERATION  
In normal (masked ROM) mode, the Test pin is tied to VSS. A reset enables access to the 16/8/4-Kbyte on-chip  
ROM (The external interface is not automatically configured).  
NOTE  
To program the duration of the oscillation stabilization interval, you make the appropriate settings to the  
basic timer control register, BTCON, before entering Stop mode. Also, if you do not want to use the basic  
timer watchdog function (which causes a system reset if a basic timer counter overflow occurs), you can  
disable it by writing "1010B" to the upper nibble of BTCON.  
8-1  
RESET and POWER-DOWN  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
HARDWARE RESET VALUES  
Table 8-1, 8-2, 8-3 list the reset values for CPU and system registers, peripheral control registers, and peripheral  
data registers following a reset operation. The following notation is used to represent reset values:  
A "1" or a "0" shows the reset bit value as logic one or logic zero, respectively.  
An "x" means that the bit value is undefined after a reset.  
A dash ("–") means that the bit is either not used or not mapped, but read 0 is the bit value.  
Table 8-1. S3C8275X/C8278X/C8274X Set 1 Register and Values After RESET  
Register Name  
Mnemonic  
Address  
Dec Hex  
Locations D0H – D2H are not mapped.  
Bit Values After RESET  
7
6
5
4
3
2
1
0
Basic timer control register  
System clock control register  
System flags register  
BTCON  
CLKCON  
FLAGS  
RP0  
211  
212  
213  
214  
215  
216  
217  
218  
219  
220  
221  
222  
223  
D3H  
D4H  
D5H  
D6H  
D7H  
D8H  
D9H  
DAH  
DBH  
DCH  
DDH  
DEH  
DFH  
0
0
x
1
1
x
x
x
x
0
x
0
0
0
x
1
1
x
x
x
x
0
x
0
0
x
0
0
x
x
x
x
0
x
0
0
0
x
0
0
x
x
x
x
0
x
x
0
0
0
x
0
1
x
x
x
x
0
x
x
0
0
x
x
x
x
x
0
x
x
0
0
0
x
x
x
x
0
x
0
0
0
0
x
x
x
x
0
x
0
0
Register pointer 0  
Register pointer 1  
RP1  
Stack pointer (high byte)  
Stack pointer (low byte)  
Instruction pointer (high byte)  
Instruction pointer (low byte)  
Interrupt request register  
Interrupt mask register  
System mode register  
Register page pointer  
SPH  
SPL  
IPH  
IPL  
IRQ  
IMR  
SYM  
PP  
8-2  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
RESET and POWER-DOWN  
Table 8-2. S3C8275X/C8278X/C8274X Set 1, Bank 0 Register Values After RESET  
Register Name  
Mnemonic  
Address  
Dec  
Bit Values After RESET  
Hex  
E0H  
E1H  
E2H  
E3H  
E4H  
E5H  
E6H  
E7H  
E8H  
E9H  
EAH  
EBH  
ECH  
EDH  
EEH  
EFH  
F0H  
F1H  
F2H  
F3H  
F4H  
F5H  
F6H  
F7H  
F8H  
F9H  
7
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
6
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
5
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
4
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
3
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
2
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Oscillator control register  
OSCCON  
SIOCON  
SIODATA  
SIOPS  
P0CONH  
P0CONL  
P0PUR  
P1CONH  
P1CONL  
P1PUR  
P2CONH  
P2CONL  
P2PUR  
P3CONH  
P3CONL  
P3PUR  
P0  
224  
225  
226  
227  
228  
229  
230  
231  
232  
233  
234  
235  
236  
237  
238  
239  
240  
241  
242  
243  
244  
245  
246  
247  
248  
249  
SIO control register  
SIO data register  
SIO pre-scaler register  
Port 0 control register (high byte)  
Port 0 control register (low byte)  
Port 0 pull-up resistor enable register  
Port 1 control register (high byte)  
Port 1 control register (low byte)  
Port 1 pull-up resistor enable register  
Port 2 control register (high byte)  
Port 2 control register (low byte)  
Port 2 pull-up resistor enable register  
Port 3 control register (high byte)  
Port 3 control register (low byte)  
Port 3 pull-up resistor enable register  
Port 0 data register  
Port 1 data register  
P1  
Port 2 data register  
P2  
Port 3 data register  
P3  
Port 4 data register  
P4  
Port 5 data register  
P5  
Port 6 data register  
P6  
External interrupt pending register  
EXTIPND  
External interrupt control register (high byte) EXTICONH  
External interrupt control register (low byte) EXTICONL  
Location FAH is not mapped.  
STPCON 251  
Location FCH is not mapped.  
BTCNT 253  
Location FEH is not mapped.  
IPR 255  
STOP control register  
Basic timer counter  
FBH  
FDH  
FFH  
0
0
x
0
0
x
0
0
x
0
0
x
0
0
x
0
0
x
0
0
x
0
0
x
Interrupt priority register  
8-3  
RESET and POWER-DOWN  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Table 8-3. S3C8275X/C8278X/C8274X Set 1, Bank 1 Register Values After RESET  
Register Name  
Mnemonic  
Address  
Bit Values After RESET  
Dec  
Hex  
7
6
5
4
3
2
1
0
LCD control register  
LCON  
WTCON  
TACNT  
224  
225  
226  
227  
228  
229  
230  
231  
232  
233  
234  
235  
236  
237  
E0H  
E1H  
E2H  
E3H  
E4H  
E5H  
E6H  
E7H  
E8H  
E9H  
EAH  
EBH  
ECH  
EDH  
0
0
0
0
1
1
0
0
0
0
0
0
0
0
0
0
1
1
0
0
0
0
0
0
0
0
0
0
0
1
1
0
0
0
0
0
0
0
0
0
0
0
1
1
0
0
0
0
0
0
0
0
0
0
0
1
1
0
0
0
0
0
0
0
0
0
0
0
1
1
0
0
0
0
0
0
0
0
0
0
0
1
1
0
0
0
0
0
0
0
0
0
0
0
1
1
0
0
0
0
0
0
0
0
Watch timer control register  
Timer A counter  
Timer B counter  
TBCNT  
Timer A data register  
TADATA  
TBDATA  
TACON  
TBCON  
CLOCON  
P4CONH  
P4CONL  
P5CONH  
P5CONL  
P6CON  
Timer B data register  
Timer 1/A control register  
Timer B control register  
Clock output control register  
Port 4 control register (high byte)  
Port 4 control register (low byte)  
Port 5 control register (high byte)  
Port 5 control register (low byte)  
Port 6 control register  
Locations EEH – EFH are not mapped.  
Flash memory control register  
FMCON  
FMUSR  
240  
241  
242  
243  
244  
F0H  
F1H  
F2H  
F3H  
F4H  
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Flash memory user programming enable register  
Flash memory sector address register (high byte) FMSECH  
Flash memory sector address register (low byte)  
Battery level detector control register  
FMSECL  
BLDCON  
Locations F5H – FFH are not mapped.  
8-4  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
RESET and POWER-DOWN  
POWER-DOWN MODES  
STOP MODE  
Stop mode is invoked by the instruction STOP (opcode 7FH). In Stop mode, the operation of the CPU and all  
peripherals is halted. That is, the on-chip main oscillator stops and the supply current is reduced to less than  
3 µA. All system functions stop when the clock “freezes”, but data stored in the internal register file is retained.  
Stop mode can be released in one of two ways: by a reset or by interrupts, for more details see Figure 7-7.  
NOTE  
Do not use stop mode if you are using an external clock source because XIN or XTIN input must be  
restricted internally to VSS to reduce current leakage.  
Using nRESET to Release Stop Mode  
Stop mode is released when the nRESET signal is released and returns to high level: all system and peripheral  
control registers are reset to their default hardware values and the contents of all data registers are retained. A  
reset operation automatically selects a slow clock fxx/16 because CLKCON.3 and CLKCON.4 are cleared to  
‘00B’. After the programmed oscillation stabilization interval has elapsed, the CPU starts the system initialization  
routine by fetching the program instruction stored in ROM location 0100H (and 0101H)  
Using an External Interrupt to Release Stop Mode  
External interrupts with an RC-delay noise filter circuit can be used to release Stop mode. Which interrupt you can  
use to release Stop mode in a given situation depends on the microcontroller’s current internal operating mode.  
The external interrupts in the S3C8275X/C8278X/C8274X interrupt structure that can be used to release Stop  
mode are:  
External interrupts P0.0–P0.2 (INT0INT2) and P1.3P1.7 (INT3INT7)  
Please note the following conditions for Stop mode release:  
If you release Stop mode using an external interrupt, the current values in system and peripheral control  
registers are unchanged except STPCON register.  
If you use an internal or external interrupt for Stop mode release, you can also program the duration of the  
oscillation stabilization interval. To do this, you must make the appropriate control and clock settings before  
entering Stop mode.  
When the Stop mode is released by external interrupt, the CLKCON.4 and CLKCON.3 bit-pair setting remains  
unchanged and the currently selected clock value is used.  
The external interrupt is serviced when the Stop mode release occurs. Following the IRET from the service  
routine, the instruction immediately following the one that initiated Stop mode is executed.  
How to Enter into Stop Mode  
Handling STPCON register then writing Stop instruction (keep the order).  
LD  
STPCON, #10100101B  
STOP  
NOP  
NOP  
NOP  
8-5  
RESET and POWER-DOWN  
IDLE MODE  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Idle mode is invoked by the instruction IDLE (opcode 6FH). In idle mode, CPU operations are halted while some  
peripherals remain active. During idle mode, the internal clock signal is gated away from the CPU, but all  
peripherals remain active. Port pins retain the mode (input or output) they had at the time idle mode was entered.  
There are two ways to release idle mode:  
1. Execute a reset. All system and peripheral control registers are reset to their default values and the contents  
of all data registers are retained. The reset automatically selects the slow clock fxx/16 because CLKCON.4  
and CLKCON.3 are cleared to ‘00B’. If interrupts are masked, a reset is the only way to release idle mode.  
2. Activate any enabled interrupt, causing idle mode to be released. When you use an interrupt to release idle  
mode, the CLKCON.4 and CLKCON.3 register values remain unchanged, and the currently selected clock  
value is used. The interrupt is then serviced. When the return-from-interrupt (IRET) occurs, the instruction  
immediately following the one that initiated idle mode is executed.  
8-6  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
I/O PORTS  
9
I/O PORTS  
OVERVIEW  
The S3C8275X/C8278X/C8274X microcontroller has seven bit-programmable I/O ports, P0P6. Port 0port 5 are  
8-bit ports, port 6 is 4-bit. This gives a total of 52 I/O pins. Each port can be flexibly configured to meet application  
design requirements.  
The CPU accesses ports by directly writing or reading port registers. No special I/O instructions are required. All  
ports of the S3C8275X/C8278X/C8274X can be configured to input or output mode. P2P6 are shared with LCD  
signals.  
Table 9-1 gives you a general overview of S3C8275X/C8278X/C8274X I/O port functions.  
Table 9-1. S3C8275X/C8278X/C8274X Port Configuration Overview  
Port  
Configuration Options  
0
1-bit programmable I/O port.  
Schmitt trigger input or push-pull, open-drain output and software assignable pull-ups.  
Alternatively P0.0P0.2 can be used as input for external interrupts INT and P0.3-P0.7 can be  
used as T1CLK, TAOUT, TBOUT, CLKOUT, and BUZ.  
1
1-bit programmable I/O port.  
Schmitt trigger input or push-pull, open-drain output and software assignable pull-ups.  
Alternatively P1.3P1.7 can be used as input for external interrupts INT and P1.0P1.2 can be  
used as SCK, SO, and SI.  
2
3
4
5
6
1-bit programmable I/O port.  
Input or push-pull, open-drain output and software assignable pull-ups.  
Alternatively P2 can be used as outputs for LCD segment signals.  
1-bit programmable I/O port.  
Input or push-pull, open-drain output and software assignable pull-ups.  
Alternatively P3 can be used as outputs for LCD segment signals.  
1-bit programmable I/O port.  
Input or push-pull output and software assignable pull-ups.  
Alternatively P4 can be used as outputs for LCD segment signals.  
1-bit programmable I/O port.  
Input or push-pull output and software assignable pull-ups.  
Alternatively P5 can be used as outputs for LCD segment signals.  
1-bit programmable I/O port.  
Input or push-pull output and software assignable pull-ups.  
Alternately P6.0P6.3 can be used as outputs for LCD common signals.  
9-1  
I/O PORTS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
PORT DATA REGISTERS  
Table 9-2 gives you an overview of the register locations of all seven S3C8275X/C8278X/C8274X I/O port data  
registers. Data registers for ports 0, 1, 2, 3, 4, 5, and 6 have the general format shown in Figure 9-1.  
Table 9-2. Port Data Register Summary  
Register Name  
Port 0 data register  
Mnemonic  
Decimal  
240  
Hex  
F0H  
F1H  
F2H  
F3H  
F4H  
F5H  
F6H  
Location  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
R/W  
P0  
P1  
P2  
P3  
P4  
P5  
P6  
Set 1, Bank 0  
Set 1, Bank 0  
Set 1, Bank 0  
Set 1, Bank 0  
Set 1, Bank 0  
Set 1, Bank 0  
Set 1, Bank 0  
Port 1 data register  
Port 2 data register  
Port 3 data register  
Port 4 data register  
Port 5 data register  
Port 6 data register  
241  
242  
243  
244  
245  
246  
S3C8275X/C8278X/C8274X I/O Port Data Register Format (n = 0-6)  
MSB .7 .6 .5 .4 .3 .2 .1 .0 LSB  
Pn.7 Pn.6 Pn.5 Pn.4 Pn.3 Pn.2 Pn.1 Pn.0  
Figure 9-1. S3C8275X/C8278X/C8274X I/O Port Data Register Format  
9-2  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
PORT 0  
I/O PORTS  
Port 0 is an 8-bit I/O port with individually configurable pins. Port 0 pins are accessed directly by writing or reading  
the port 0 data register, P0 at location F0H in set 1, bank 0. P0.0-P0.7 can serve as inputs (with or without pull-  
up), as outputs (push-pull or open-drain) or you can be configured the following functions.  
Low-nibble pins (P0.0P0.3): INT0–INT2, T1CLK  
High-nibble pins (P0.4P0.7): TAOUT, TBOUT, CLKOUT, BUZ  
Port 0 Control Registers (P0CONH, P0CONL)  
Port 0 has two 8-bit control registers: P0CONH for P0.4P0.7 and P0CONL for P0.0P0.3. A reset clears the  
P0CONH and P0CONL registers to "00H", configuring P0.0P0.2 pins to input mode with interrupt and P0.3P0.7  
pins to input mode. You use control registers setting to select input or output mode (push-pull or open-drain) and  
enable the alternative functions.  
When programming this port, please remember that any alternative peripheral I/O function you configure using the  
port 0 control registers must also be enabled in the associated peripheral module.  
Port 0 Pull-up Resistor Control Register (P0PUR)  
Using the port 0 pull-up resistor control register, P0PUR (E6H, set 1, bank 0) you can configure pull-up resistors  
to individual port 0 pins.  
Port 0 Interrupt Control Registers (EXTICONL.5.0, EXTIPND.2.0)  
To process external interrupts at the port 0 pins, two additional control registers are provided: the external  
interrupt control register EXTICONL.5.0 (F9H, set 1, bank 0) and the external interrupt pending register  
EXTIPND.2.0 (F7H, set 1, bank 0)  
The external interrupt pending register EXTIPND.2.0 lets you check for interrupt pending conditions and clear  
the pending condition when the interrupt service routine has been initiated. The application program detects  
interrupt requests by polling the EXTIPND.2.0 register at regular intervals.  
When the interrupt enable bit of any port 0 pin is "1", a rising or falling edge at that pin will generate an interrupt  
request. The corresponding pending bit is then automatically set to "1" and the IRQ level goes low to signal the  
CPU that an interrupt request is waiting. When the CPU acknowledges the interrupt request, application software  
must the clear the pending condition by writing a "0" to the corresponding EXTIPND bit.  
9-3  
I/O PORTS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Port 0 Control Register, High Byte (P0CONH)  
E4H, Set 1, Bank 0, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
P0.7/BUZ  
P0.5/TBOUT  
P0.6/CLKOUT  
P0.4/TAOUT  
P0CONH bit-pair pin configuration settings:  
00  
01  
10  
11  
Schmitt trigger input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function  
(BUZ, CLKOUT, TBOUT, TAOUT)  
Figure 9-2. Port 0 High-Byte Control Register (P0CONH)  
Port 0 Control Register, Low Byte (P0CONL)  
E5H, Set 1, Bank 0, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
P0.3/T1CLK P0.2/INT2  
P0.1/INT1  
P0.0/INT0  
P0CONL bit-pair pin configuration settings:  
00  
01  
10  
11  
Schmitt trigger input mode (T1CLK)  
N-channel open-drain output mode  
Push-pull output mode  
Not available  
Figure 9-3. Port 0 Low-Byte Control Register (P0CONL)  
9-4  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
I/O PORTS  
Port 0 Pull-up Control Register (P0PUR)  
E6H, Set 1, Bank 0, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
P0.7 P0.6 P0.5 P0.4  
P0PUR bit configuration settings:  
P0.3 P0.2 P0.1 P0.0  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
NOTE: A pull-up resistor of port 0 is automatically disabled when the  
corresponding pin is selected as push-pull output or alternative  
function.  
Figure 9-4. Port 0 Pull-up Control Register (P0PUR)  
External Interrupt Control Register, Low Byte (EXTICONL)  
E9H, Set 1, Bank 0, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
P1.3/INT3  
P0.2/INT2  
P0.1/INT1  
P0.0/INT0  
EXTICONL bit configuration settings:  
00  
01  
10  
11  
Disable interrupt  
Enable interrupt by falling edge  
Enable interrupt by rising edge  
Enable interrupt by both falling and rising edge  
Figure 9-5. External Interrupt Control Register, Low Byte (EXTICONL)  
9-5  
I/O PORTS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
External Interrupt Pending Register (EXTIPND)  
F7H, Set 1, Bank 0, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
P1.7 P1.6 P1.5 P1.4 P1.3 P0.2 P0.1 P0.0  
(INT7) (INT6) (INT5) (INT4) (INT3) (INT2) (INT1) (INT0)  
EXTIPND bit configuration settings:  
0
1
No interrupt pending (when read), clear pending bit (when write)  
Interrupt is pending (when read)  
Figure 9-6. External Interrupt Pending Register (EXTIPND)  
9-6  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
PORT 1  
I/O PORTS  
Port 1 is an 8-bit I/O port with individually configurable pins. Port 1 pins are accessed directly by writing or reading  
the port 1 data register, P1 at location F1H in set 1, bank 0. P1.0P1.7 can serve as inputs (with or without pull-  
up), as outputs (push-pull or open-drain) or you can be configured the following functions.  
Low-nibble pins (P1.0P1.3): SCK, SO, SI, INT3  
High-nibble pins (P1.4P1.7): INT4INT7  
Port 1 Control Registers (P1CONH, P1CONL)  
Port 1 has two 8-bit control registers: P1CONH for P1.4P1.7 and P1CONL for P1.0P1.3. A reset clears the  
P1CONH and P1CONL registers to "00H", configuring P1.3P1.7 pins to input mode with interrupt and P1.0P1.2  
pins to input mode. You use control registers setting to select input or output mode (push-pull or open-drain) and  
enable the alternative functions.  
When programming this port, please remember that any alternative peripheral I/O function you configure using the  
port 1 control registers must also be enabled in the associated peripheral module.  
Port 1 Pull-up Resistor Control Register (P1PUR)  
Using the port 1 pull-up resistor control register, P1PUR (E9H, set 1, bank 0), you can configure pull-up resistors  
to individual port 1 pins.  
Port 1 Interrupt Control Registers (EXTICONH, EXTICONL.7.6, EXTIPND.7.3)  
To process external interrupts at the port 1 pins, three additional control registers are provided: the external  
interrupt control registers EXTICONH/EXTICONL.7.6 (F8H/F9H, set 1, bank 0) and the external interrupt  
pending register EXTIPND.7.3 (F7H, set 1, bank 0).  
The external interrupt pending register EXTIPND.7.3 lets you check for interrupt pending conditions and clear  
the pending condition when the interrupt service routine has been initiated. The application program detects  
interrupt requests by polling the EXTIPND.7.3 register at regular intervals.  
When the interrupt enable bit of any port 1 pin is "1", a rising or falling edge at that pin will generate an interrupt  
request. The corresponding pending bit is then automatically set to "1" and the IRQ level goes low to signal the  
CPU that an interrupt request is waiting. When the CPU acknowledges the interrupt request, application software  
must the clear the pending condition by writing a "0" to the corresponding EXTIPND bit.  
9-7  
I/O PORTS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Port 1 Control Register, High Byte (P1CONH)  
E7H, Set 1, Bank 0, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
P1.7/INT7  
P1.6/INT6  
P1.5/INT5  
P1.4/INT4  
P1CONH bit-pair pin configuration settings:  
00  
01  
10  
11  
Schmitt trigger input mode  
N-channel open-drain output mode  
Push-pull output mode  
Not available  
Figure 9-7. Port 1 High-Byte Control Register (P1CONH)  
Port 1 Control Register, Low Byte (P1CONL)  
E8H, Set 1, Bank 0, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
P1.3/INT3  
P1.2/SI  
P1.1/SO  
P1.0/SCK  
P1CONL bit-pair pin configuration settings:  
00  
01  
10  
11  
Schmitt trigger input mode (SI, SCK)  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (SCK, SO)  
Figure 9-8. Port 1 Low-Byte Control Register (P1CONL)  
9-8  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
I/O PORTS  
Port 1 Pull-up Control Register (P1PUR)  
E9H, Set 1, Bank 0, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
P1.7 P1.6 P1.5 P1.4  
P1PUR bit configuration settings:  
P1.3 P1.2 P1.1 P1.0  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
NOTE:  
A pull-up resistor of port 1 is automatically disabled when the  
corresponding pin is selected as push-pull output or alternative  
function.  
Figure 9-9. Port 1 Pull-up Control Register (P1PUR)  
External Interrupt Control Register, High Byte (EXTICONH)  
F8H, Set 1, Bank 0, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
P1.7/INT7  
P1.6/INT6  
P1.5/INT5  
P1.4/INT4  
EXTICONH bit configuration settings:  
00  
01  
10  
11  
Disable interrupt  
Enable interrupt by falling edge  
Enable interrupt by rising edge  
Enable interrupt by both falling and rising edge  
Figure 9-10. External Interrupt Control Register, High Byte (EXTICONH)  
9-9  
I/O PORTS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
External Interrupt Control Register, Low Byte (EXTICONL)  
F9H, Set 1, Bank 0, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
P1.3/INT3  
P0.2/INT2  
P0.1/INT1  
P0.0/INT0  
EXTICONL bit configuration settings:  
00  
01  
10  
11  
Disable interrupt  
Enable interrupt by falling edge  
Enable interrupt by rising edge  
Enable interrupt by both falling and rising edge  
Figure 9-11. External Interrupt Control Register, Low Byte (EXTICONL)  
External Interrupt Pending Register (EXTIPND)  
F7H, Set 1, Bank 0, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
P1.7 P1.6 P1.5 P1.4 P1.3 P0.2 P0.1 P0.0  
(INT7) (INT6) (INT5) (INT4) (INT3) (INT2) (INT1) (INT0)  
EXTIPND bit configuration settings:  
0
1
No interrupt pending (when read), clear pending bit (when write)  
Interrupt is pending (when read)  
Figure 9-12. External Interrupt Pending Register (EXTIPND)  
9-10  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
PORT 2  
I/O PORTS  
Port 2 is an 8-bit I/O port with individually configurable pins. Port 2 pins are accessed directly by writing or reading  
the port 2 data register, P2 at location F2H in set 1, Bank 0. P2.0-P2.7 can serve as inputs (with or without pull-  
up), as outputs (push-pull or open-drain) or you can be configured the following functions.  
Low-nibble pins (P2.0-P2.3): SEG31SEG28, VBLDREF  
High-nibble pins (P2.4-P2.7): SEG27SEG24  
Port 2 Control Registers (P2CONH, P2CONL)  
Port 2 has two 8-bit control registers: P2CONH for P2.4-P2.7 and P2CONL for P2.0-P2.3. A reset clears the  
P2CONH and P2CONL registers to "00H", configuring all pins to input mode. You use control registers setting to  
select input or output mode (push-pull or open-drain) and enable the alternative functions.  
When programming this port, please remember that any alternative peripheral I/O function you configure using the  
port 2 control registers must also be enabled in the associated peripheral module.  
Port 2 Pull-up Resistor Control Register (P2PUR)  
Using the port 2 pull-up resistor control register, P2PUR (ECH, set 1, bank 0), you can configure pull-up resistors  
to individual port 2 pins.  
Port 2 Control Register, High Byte (P2CONH)  
EAH, Set 1, Bank 0, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
P2.7/SEG24 P2.6/SEG25 P2.5/SEG26 P2.4/SEG27  
P2CONH bit-pair pin configuration settings:  
00  
01  
10  
11  
Input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (SEG24-SEG27)  
Figure 9-13. Port 2 High-byte Control Register (P2CONH)  
9-11  
I/O PORTS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Port 2 Control Register, Low Byte (P2CONL)  
EBH, Set 1, Bank 0, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
P2.3/SEG28 P2.2/SEG29 P2.1/SEG30  
P2CONL bit-pair pin configuration settings:  
P2.0/SEG31/VBLDREF  
00  
01  
10  
11  
Input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (SEG28-SEG31/VBLDREF  
)
Figure 9-14. Port 2 Low-byte Control Register (P2CONL)  
Port 2 Pull-up Control Register (P2PUR)  
ECH, Set 1, Bank 0, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
P2.7 P2.6 P2.5 P2.4 P2.3 P2.2 P2.1 P2.0  
P2PUR bit configuration settings:  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
NOTE:  
A pull-up resistor of port 2 is automatically disabled when the  
corresponding pin is selected as push-pull output or alternative  
function.  
Figure 9-15. Port 2 Pull-up Control Register (P2PUR)  
9-12  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
PORT 3  
I/O PORTS  
Port 3 is an 8-bit I/O port with individually configurable pins. Port 3 pins are accessed directly by writing or reading  
the port 3 data register, P3 at location F3H in set 1, bank 0. P3.0-P3.7 can serve as inputs (with or without pull-  
up), as outputs (push-pull or open-drain) or you can be configured the following functions.  
Low-nibble pins (P3.0-P3.3): SEG23-SEG20  
High-nibble pins (P3.4-P3.7): SEG19-SEG16  
Port 3 Control Registers (P3CONH, P3CONL)  
Port 3 has two 8-bit control registers: P3CONH for P3.4-P3.7 and P3CONL for P3.0-P3.3. A reset clears the  
P3CONH and P3CONL registers to "00H", configuring all pins to input mode. You use control registers setting to  
select input or output mode (push-pull or open-drain) and enable the alternative functions.  
When programming this port, please remember that any alternative peripheral I/O function you configure using the  
port 3 control registers must also be enabled in the associated peripheral module.  
Port 3 Pull-up Resistor Control Register (P3PUR)  
Using the port 3 pull-up resistor control register, P3PUR (EFH, set 1, bank 0), you can configure pull-up resistors  
to individually port 3 pins.  
Port 3 Control Register, High Byte (P3CONH)  
EDH, Set 1, Bank 0, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
P3.7/SEG16 P3.6/SEG17 P3.5/SEG18 P3.4/SEG19  
P3CONH bit-pair pin configuration settings:  
00  
01  
10  
11  
Input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative fumction (SEG16-SEG19)  
Figure 9-16. Port 3 High Byte Control Register (P3CONH)  
9-13  
I/O PORTS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Port 3 Control Register, Low Byte (P3CONL)  
EEH, Set 1, Bank 0, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
P3.3/SEG20 P3.2/SEG21 P3.1/SEG22 P3.0/SEG23  
P3CONL bit-pair pin configuration settings:  
00  
01  
10  
11  
Input mode  
N-channel open-drain output mode  
Push-pull output mode  
Alternative function (SEG20-SEG23)  
Figure 9-17. Port 3 Low Byte Control Register (P3CONL)  
Port 3 Pull-up Control Register (P3PUR)  
EFH, Set 1, Bank 0, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
P3.7 P3.6 P3.5 P3.4 P3.3 P3.2 P3.1 P3.0  
P3PUR bit configuration settings:  
0
1
Disable pull-up resistor  
Enable pull-up resistor  
NOTE:  
A pull-up resistor of port 3 is automatically disabled when the  
corresponding pin is selected as push-pull output or alternative  
function.  
Figure 9-18. Port 3 Pull-up Control Register (P3PUR)  
9-14  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
PORT 4  
I/O PORTS  
Port 4 is an 8-bit I/O port with individually configurable pins. Port 4 pins are accessed directly by writing or reading  
the port 4 data register, P4 at location F4H in set 1, bank 0. P4.0-P4.7 can serve as inputs (with or without pull-  
up), as push-pull output or you can be configured the following functions.  
Low-nibble pins (P4.0-P4.3): SEG15-SEG12  
High-nibble pins (P4.4-P4.7): SEG11-SEG8  
Port 4 Control Registers (P4CONH, P4CONL)  
Port 4 has two 8-bit control registers: P4CONH for P4.4-P4.7 and P4CONL for P4.0-P4.3. A reset clears the  
P4CONH and P4CONL registers to "00H", configuring all pins to input mode. You use control registers setting to  
select input (with or without pull-up) or push-pull output mode and enable the alternative functions.  
When programming this port, please remember that any alternative peripheral I/O function you configure using the  
port 4 control registers must also be enabled in the associated peripheral module.  
Port 4 Control Register, High Byte (P4CONH)  
E9H, Set 1, Bank 1, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
P4.7/SEG8 P4.6/SEG9 P4.5/SEG10 P4.4/SEG11  
P4CONH bit-pair pin configuration settings:  
00  
01  
10  
11  
Input mode  
Input with pull-up resistor  
Push-pull output mode  
Alternative function (SEG8-SEG11)  
Figure 9-19. Port 4 High-Byte Control Register (P4CONH)  
9-15  
I/O PORTS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Port 4 Control Register, Low Byte (P4CONL)  
EAH, Set 1, Bank 1, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
P4.3/SEG12 P4.2/SEG13 P4.1/SEG14 P4.0/SEG15  
P4CONH bit-pair pin configuration settings:  
00  
01  
10  
11  
Input mode  
Input with pull-up resistor  
Push-pull output mode  
Alternative function (SEG12-SEG15)  
Figure 9-20. Port 4 Low-Byte Control Register (P4CONL)  
9-16  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
PORT 5  
I/O PORTS  
Port 5 is an 8-bit I/O port with individually configurable pins. Port 5 pins are accessed directly by writing or reading  
the port 5 data register, P5 at location F5H in set 1, bank 0. P5.0-P5.7 can serve as inputs (with or without pull-  
up), as push-pull output or you can be configured the following functions.  
Low-nibble pins (P5.0-P5.3): SEG7SEG4  
High-nibble pins (P5.4-P5.7): SEG3SEG0  
Port 5 Control Registers (P5CONH, P5CONL)  
Port 5 has two 8-bit control registers: P5CONH for P5.4-P5.7 and P5CONL for P5.0-P5.3. A reset clears the  
P5CONH and P5CONL registers to "00H", configuring all pins to input mode. You use control registers setting to  
select input (with or without pull-up) or push-pull output mode and enable the alternative functions.  
When programming this port, please remember that any alternative peripheral I/O function you configure using the  
port 5 control registers must also be enabled in the associated peripheral module.  
Port 5 Control Register, High Byte (P5CONH)  
EBH, Set 1, Bank 1, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
P5.7/SEG0 P5.6/SEG1 P5.5/SEG2  
P5.4/SEG3  
P5CONH bit-pair pin configuration settings:  
00  
01  
10  
11  
Input mode  
Input with pull-up resistor  
Push-pull output mode  
Alternative function (SEG0-SEG3)  
Figure 9-21. Port 5 High-Byte Control Register (P5CONH)  
9-17  
I/O PORTS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Port 5 Control Register, Low Byte (P5CONL)  
ECH, Set 1, Bank 1, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
P5.3/SEG4 P5.2/SEG5 P5.1/SEG6  
P5.0/SEG7  
P5CONL bit-pair pin configuration settings:  
00  
01  
10  
11  
Input mode  
Input with pull-up resistor  
Push-pull output mode  
Alternative function (SEG4-SEG7)  
Figure 9-22. Port 5 Low-Byte Control Register (P5CONL)  
9-18  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
PORT 6  
I/O PORTS  
Port 6 is a 4-bit I/O port with individually configurable pins. Port 6 pins are accessed directly by writing or reading  
the port 6 data register, P6 at location F6H in set 1, bank 0. P6.0-P6.3 can serve as inputs (with or without pull-  
up), as push-pull output or you can be configured the following functions.  
Low-nibble pins (P6.0-P6.3): COM0COM3  
Port 6 Control Register (P6CON)  
Port 6 has an 8-bit control register: P6CON for P6.0-P6.3. A reset clears the P6CON register to "00H", configuring  
all pins to input mode. You use control register setting to select input (with or without pull-up) or push-pull output  
mode and enable the alternative functions.  
When programming this port, please remember that any alternative peripheral I/O function you configure using the  
port 6 control register must also be enabled in the associated peripheral module.  
Port 6 Control Register (P6CON)  
EDH, Set 1, Bank 1, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
P6.3/COM3 P6.2/COM2 P6.1/COM1 P6.0/COM0  
P6CON bit-pair pin configuration settings:  
00  
01  
10  
11  
Input mode  
Input with pull-up resistor  
Push-pull output mode  
Alternative function (COM3-COM0)  
Figure 9-23. Port 6 Control Register (P6CON)  
9-19  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
BASIC TIMER  
10 BASIC TIMER  
OVERVIEW  
Basic timer (BT) can be used in two different ways:  
As a watchdog timer to provide an automatic reset mechanism in the event of a system malfunction.  
To signal the end of the required oscillation stabilization interval after a reset or a stop mode release.  
The functional components of the basic timer block are:  
Clock frequency divider (fxx divided by 4096, 1024, 128, or 16) with multiplexer  
8-bit basic timer counter, BTCNT (set 1, bank 0, FDH, read-only)  
Basic timer control register, BTCON (set 1, D3H, read/write)  
10-1  
BASIC TIMER  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
BASIC TIMER CONTROL REGISTER (BTCON)  
The basic timer control register, BTCON, is used to select the input clock frequency, to clear the basic timer  
counter and frequency dividers, and to enable or disable the watchdog timer function. It is located in set 1,  
address D3H, and is read/write addressable using Register addressing mode.  
A reset clears BTCON to "00H". This enables the watchdog function and selects a basic timer clock frequency of  
fxx/4096. To disable the watchdog function, you must write the signature code "1010B" to the basic timer register  
control bits BTCON.7–BTCON.4.  
The 8-bit basic timer counter, BTCNT (set 1, bank 0, FDH), can be cleared at any time during normal operation by  
writing a "1" to BTCON.1. To clear the frequency dividers for all timers input clock, you write a "1" to BTCON.0.  
Basic Timer Control Register (BTCON)  
D3H, Set 1, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
Divider clear bit for all timers:  
0 = No effect  
1 = Clear divider  
Watchdog function enable bits:  
1010B  
= Disable watchdog timer  
Other values = Enable watchdog timer  
Basic timer counter clear bit:  
0 = No effect  
1 = Clear BTCNT  
Basic timer input clock selection bits:  
00 = fXX/4096  
01 = fXX/1024  
10 = fXX/128  
11 = fXX/16  
Figure 10-1. Basic Timer Control Register (BTCON)  
10-2  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
BASIC TIMER  
BASIC TIMER FUNCTION DESCRIPTION  
Watchdog Timer Function  
You can program the basic timer overflow signal (BTOVF) to generate a reset by setting BTCON.7BTCON.4 to  
any value other than "1010B". (The "1010B" value disables the watchdog function.) A reset clears BTCON to  
"00H", automatically enabling the watchdog timer function. A reset also selects the CPU clock (as determined by  
the current CLKCON register setting), divided by 4096, as the BT clock.  
A reset whenever a basic timer counter overflow occurs. During normal operation, the application program must  
prevent the overflow, and the accompanying reset operation, from occurring. To do this, the BTCNT value must  
be cleared (by writing a "1" to BTCON.1) at regular intervals.  
If a system malfunction occurs due to circuit noise or some other error condition, the BT counter clear operation  
will not be executed and a basic timer overflow will occur, initiating a reset. In other words, during normal  
operation, the basic timer overflow loop (a bit 7 overflow of the 8-bit basic timer counter, BTCNT) is always  
broken by a BTCNT clear instruction. If a malfunction does occur, a reset is triggered automatically.  
Oscillation Stabilization Interval Timer Function  
You can also use the basic timer to program a specific oscillation stabilization interval following a reset or when  
stop mode has been released by an external interrupt.  
In stop mode, whenever a reset or an internal and an external interrupt occurs, the oscillator starts. The BTCNT  
value then starts increasing at the rate of fxx/4096 (for reset), or at the rate of the preset clock source (for an  
internal and an external interrupt). When BTCNT.4 overflows, a signal is generated to indicate that the  
stabilization interval has elapsed and to gate the clock signal off to the CPU so that it can resume normal  
operation.  
In summary, the following events occur when stop mode is released:  
1. During stop mode, a power-on reset or an internal and an external interrupt occurs to trigger the stop mode  
release and oscillation starts.  
2. If a power-on reset occurred, the basic timer counter will increase at the rate of fxx/4096. If an internal and an  
external interrupt is used to release stop mode, the BTCNT value increases at the rate of the preset clock  
source.  
3. Clock oscillation stabilization interval begins and continues until bit 4 of the basic timer counter overflows.  
4. When a BTCNT.4 overflow occurs, normal CPU operation resumes.  
10-3  
BASIC TIMER  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
RESET or STOP  
Bit 1  
Bits 3, 2  
Basic Timer Control Register  
(Write '1010xxxxB' to Disable)  
Data Bus  
f
f
f
f
XX/4096  
XX/1024  
XX/128  
XX/16  
Clear  
8-Bit Up Counter  
(BTCNT, Read-Only)  
f
XX  
DIV  
MUX  
OVF  
RESET  
Start the CPU (note)  
u
Bit 0  
NOTE:  
During a power-on reset operation, the CPU is idle during the required oscillation  
stabilization interval (until bit 4 of the basic timer counter overflows).  
Figure 10-2. Basic Timer Block Diagram  
10-4  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
TIMER 1  
11 TIMER 1  
ONE 16-BIT TIMER MODE (TIMER 1)  
The 16-bit timer 1 is used in one 16-bit timer or two 8-bit timers mode. If TACON.7 is set to "1", timer 1 is used as  
a 16-bit timer. If TACON.7 is set to "0", timer 1 is used as two 8-bit timers.  
One 16-bit timer mode (Timer 1)  
Two 8-bit timers mode (Timer A and B)  
OVERVIEW  
The 16-bit timer 1 is a 16-bit general-purpose timer. Timer 1 has the interval timer mode by using the appropriate  
TACON setting.  
Timer 1 has the following functional components:  
Clock frequency divider (fxx divided by 512, 256, 64, 8, or 1, fxt, and T1CLK: External clock) with multiplexer  
16-bit counter (TACNT, TBCNT), 16-bit comparator, and 16-bit reference data register (TADATA, TBDATA)  
Timer 1 match interrupt (IRQ 0, vector F0H) generation  
Timer 1 control register, TACON (set 1, bank 1, E6H, read/write)  
FUNCTION DESCRIPTION  
Interval Timer Function  
The timer 1 module can generate an interrupt, the timer 1 match interrupt (T1INT). T1INT belongs to the interrupt  
level IRQ 0, and is assigned a separate vector address, F0H.  
The T1INT pending condition should be cleared by software after IRQ 0 is serviced. The T1INT pending bit must  
be cleared by the application sub-routine by writing a "0" to the TACON.0 pending bit.  
In interval timer mode, a match signal is generated when the counter value is identical to the values written to the  
timer 1 reference data registers, TADATA and TBDATA. The match signal generates a timer 1 match interrupt  
and clears the counter.  
If, for example, you write the value 32H and 10H to TADATA and TBDATA, respectively, and 8EH to TACON, the  
counter will increment until it reaches 3210H. At this point, the timer 1 interrupt request is generated, the counter  
value is reset, and counting resumes.  
11-1  
TIMER 1  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Timer 1 Control Register (TACON)  
You use the timer 1 control register, TACON, to  
Enable the timer 1 operating (interval timer)  
Select the timer 1 input clock frequency  
Clear the timer 1 counter, TACNT and TBCNT  
Enable the timer 1 interrupt  
Clear timer 1 interrupt pending conditions  
TACON is located in set 1, bank 1, at address E6H, and is read/write addressable using Register addressing  
mode.  
A reset clears TACON to "00H". This sets timer 1 to disable interval timer mode, selects an input clock frequency  
of fxx/512, and disables timer 1 interrupt. You can clear the timer 1 counter at any time during the normal  
operation by writing a "1" to TACON.3.  
To enable the timer 1 interrupt (IRQ 0, vector F0H), you must write TACON.7, TACON.2, and TACON.1 to "1".  
To generate the exact time interval, you should write TACON.3 and TACON.0 to "10B", which cleared counter  
and interrupt pending bit. When the T1INT sub-routine is serviced, the pending condition must be cleared by  
software by writing a "0" to the timer 1 interrupt pending bit, TACON.0.  
Timer 1/A Control Register (TACON)  
E6H, Set 1, Bank 1, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
Timer 1 operating mode selection bit:  
0 = Two 8-bit timers mode (Timer A/B)  
1 = One 16-bit timer mode (Timer 1)  
Timer 1 interrupt pending bit:  
0 = No interrupt pending (when read)  
Clear pending bit (when write)  
1 = Interrupt is pending (when read)  
No effect (when write)  
Timer 1 interrupt enable bit:  
0 = Disable interrupt  
Timer 1 clock selection bits:  
000 = fxx/512  
1 = Enable interrupt  
001 = fxx/256  
010 = fxx/64  
011 = fxx/8  
100 = fxx  
101 = fxt (sub clock)  
110 = T1CLK (external clock)  
111 = Not available  
Timer 1 counter operating enable bit:  
0 = Disable counting operation  
1 = Enable counting operation  
Timer 1 counter clear bit:  
0 = No affect  
1 = Clear the timer 1 counter (when write)  
Figure 11-1. Timer 1/A Control Register (TACON)  
11-2  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
TIMER 1  
BTCON.0  
TACON.6-.4  
1/512  
1/256  
1/64  
1/8  
R
TACON.3  
Data Bus  
TACON.2  
(XIN or XTIN  
)
LSB  
MSB  
M
U
X
DIV  
fxx  
Clear  
TBCNT TACNT  
R
TACON.1  
1/1  
Match  
16-Bit Comparator  
LSB MSB  
TACON.0  
fxt  
T1INT  
T1CLK  
TAOUT  
TBDATA TADATA  
Buffer Buffer  
Match Signal  
T1CLR  
TBDATA TADATA  
Data Bus  
NOTE:  
When one 16-bit timer mode (TACON.7 <- "1": Timer 1)  
Figure 11-2. Timer 1 Block Diagram (One 16-bit Mode)  
11-3  
TIMER 1  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
TWO 8-BIT TIMERS MODE (TIMER A and B)  
OVERVIEW  
The 8-bit timer A and B are the 8-bit general-purpose timers. Timer A and B have the interval timer mode by using  
the appropriate TACON and TBCON setting, respectively.  
Timer A and B have the following functional components:  
Clock frequency divider with multiplexer  
fxx divided by 512, 256, 64, 8 or 1, fxt, and T1CLK (External clock) for timer A  
fxx divided by 512, 256, 64 or 8 and fxt for timer B  
8-bit counter (TACNT, TBCNT), 8-bit comparator, and 8-bit reference data register (TADATA, TBDATA)  
Timer A have I/O pin for match output (TAOUT)  
Timer A match interrupt (IRQ 0, vector F0H) generation  
Timer A control register, TACON (set 1, bank 1, E6H, read/write)  
Timer B have I/O pin for match output (TBOUT)  
Timer B match interrupt (IRQ 0, vector F2H) generation  
Timer B control register, TBCON (set 1, bank 1, E7H, read/write)  
FUNCTION DESCRIPTION  
Interval Timer Function  
The timer A and B module can generate an interrupt: the timer A match interrupt (TAINT) and the timer B match  
interrupt (TBINT). TAINT belongs to the interrupt level IRQ 0, and is assigned a separate vector address, F0H.  
TBINT belongs to the interrupt level IRQ 0 and is assigned a separate vector address, F2H.  
The TAINT and TBINT pending condition should be cleared by software after they are serviced.  
In interval timer mode, a match signal is generated when the counter value is identical to the values written to the  
TA or TB reference data registers, TADATA and TBDATA. The match signal generates corresponding match  
interrupt (TAINT, vector F0H; TBINT, vector F2H) and clears the counter.  
If, for example, you write the value 10H to TBDATA, "0" to TACON.7, and 0EH to TBCON, the counter will  
increment until it reaches 10H. At this point, the TB interrupt request is generated, the counter value is reset, and  
counting resumes.  
Timer A and B Control Register (TACON, TBCON)  
You use the timer A and B control register, TACON and TBCON, to  
Enable the timer A (interval timer mode) and B operating (interval timer mode)  
Select the timer A and B input clock frequency  
Clear the timer A and B counter, TACNT and TBCNT  
Enable the timer A and B interrupts  
Clear timer A and B interrupt pending conditions  
11-4  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
TIMER 1  
TACON and TBCON are located in set 1, bank 1, at address E6H and E7H, and is read/write addressable using  
Register addressing mode.  
A reset clears TACON to "00H". This sets timer A to disable interval timer mode, selects an input clock frequency  
of fxx/512, and disables timer A interrupt. You can clear the timer A counter at any time during normal operation  
by writing a "1" to TACON.3.  
A reset clears TBCON to "00H". This sets timer B to disable interval timer mode, selects an input clock frequency  
of fxx/512, and disables timer B interrupt. You can clear the timer B counter at any time during normal operation  
by writing a "1" to TBCON.3.  
To enable the timer A interrupt (TAINT) and timer B interrupt (TBINT), you must write TACON.7 to "0", TACON.2  
(TBCON.2) and TACON.1 (TBCON.1) to "1". To generate the exact time interval, you should write TACON.3  
(TBCON.3) and TACON.0 (TBCON.0), which cleared counter and interrupt pending bit. When the TAINT and  
TBINT sub-routine has been serviced, the pending condition must be cleared by software by writing a "0" to the  
timer A and B interrupt pending bits, TACON.0 or TBCON.0.  
Timer 1/A Control Register (TACON)  
E6H, Set 1, Bank 1, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
Timer A operating mode selection bit:  
0 = Two 8-bit timers mode (Timer A/B)  
1 = One 16-bit timer mode (Timer 1)  
Timer A interrupt pending bit:  
0 = No interrupt pending (when read)  
Clear pending bit (when write)  
1 = Interrupt is pending (when read)  
No effect (when write)  
Timer A interrupt enable bit:  
0 = Disable interrupt  
Timer A clock selection bits:  
000 = fxx/512  
1 = Enable interrupt  
001 = fxx/256  
010 = fxx/64  
011 = fxx/8  
100 = fxx  
101 = fxt (sub clock)  
110 = T1CLK (external clock)  
111 = Not available  
Timer A counter operating enable bit:  
0 = Disable counting operation  
1 = Enable counting operation  
Timer A counter clear bit:  
0 = No affect  
1 = Clear the timer A counter (when write)  
Figure 11-3. Timer 1/A Control Register (TACON)  
11-5  
TIMER 1  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Timer B Control Register (TBCON)  
E7H, Set 1, Bank 1, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
Timer B interrupt pending bit:  
0 = No interrupt pending (when read)  
Clear pending bit (when write)  
1 = Interrupt is pending (when read)  
No effect (when write)  
Not used for  
S3C8275X/C8278X/C8274X  
Timer B interrupt enable bit:  
0 = Disable interrupt  
Timer B clock selection bits:  
000 = fxx/512  
1 = Enable interrupt  
001 = fxx/256  
010 = fxx/64  
011 = fxx/8  
100 = fxt (sub clock)  
Others = Not available  
Timer B counter operating enable bit:  
0 = Disable counting operation  
1 = Enable counting operation  
Timer B counter clear bit:  
0 = No affect  
1 = Clear the timer B counter (when write)  
Figure 11-4. Timer B Control Register (TBCON)  
11-6  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
TIMER 1  
BTCON.0  
TACON.6-.4  
1/512  
1/256  
1/64  
1/8  
R
TACON.3  
MSB  
Data Bus  
TACNT  
TACON.2  
(XIN or XTIN  
)
LSB  
M
U
X
DIV  
fxx  
Clear  
(8-Bit Up-Counter)  
R
TACON.1  
1/1  
Match  
TACON.0  
8-Bit Comparator  
LSB MSB  
fxt  
TAINT  
T1CLK  
TAOUT  
TADATA Buffer  
Match Signal  
TACLR  
TADATA Register  
Data Bus  
NOTE:  
When two 8-bit timers mode (TACON.7 <- "0": Timer A)  
Figure 11-5. Timer A Block Diagram (Two 8-bit Timers Mode)  
11-7  
TIMER 1  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
BTCON.0  
TBCON.6-.4  
R
1/512  
1/256  
1/64  
1/8  
TBCON.3  
MSB  
Data Bus  
TBCNT  
TBCON.2  
M
U
X
(XIN or XTIN  
)
LSB  
DIV  
fxx  
Clear  
(8-Bit Up-Counter)  
R
TBCON.1  
Match  
TBCON.0  
8-Bit Comparator  
LSB MSB  
fxt  
TBINT  
TBOUT  
TBDATA Buffer  
Match Signal  
TBCLR  
TBDATA Register  
Data Bus  
NOTE:  
When two 8-bit timers mode (TACON.7 <- "0": Timer B)  
Figure 11-6. Timer B Block Diagram (Two 8-bit Timers Mode)  
11-8  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
WATCH TIMER  
12 WATCH TIMER  
OVERVIEW  
Watch timer functions include real-time and watch-time measurement and interval timing for the system clock. To  
start watch timer operation, set bit 1 of the watch timer control register, WTCON.1 to "1".  
And if you want to service watch timer overflow interrupt (IRQ 2, vector F6H), then set the WTCON.6 to "1".  
The watch timer overflow interrupt pending condition (WTCON.0) must be cleared by software in the application's  
interrupt service routine by means of writing a "0" to the WTCON.0 interrupt pending bit.  
After the watch timer starts and elapses a time, the watch timer interrupt pending bit (WTCON.0) is automatically  
set to "1", and interrupt requests commence in 3.91ms, 0.25, 0.5 and 1-second intervals by setting Watch timer  
speed selection bits (WTCON.3.2).  
The watch timer can generate a steady 0.5 kHz, 1 kHz, 2 kHz, or 4 kHz signal to BUZ output pin for Buzzer. By  
setting WTCON.3 and WTCON.2 to "11b", the watch timer will function in high-speed mode, generating an  
interrupt every 3.91 ms. High-speed mode is useful for timing events for program debugging sequences.  
Also, you can select watch timer clock source by setting the WTCON.7 appropriately value.  
The watch timer supplies the clock frequency for the LCD controller (fLCD ). Therefore, if the watch timer is  
disabled, the LCD controller does not operate.  
Watch timer has the following functional components:  
Real Time and Watch-Time Measurement  
Using a Main or Sub Clock Source (Main clock divided by 27(fx/128) or Sub clock(fxt))  
Clock Source Generation for LCD Controller (fLCD  
)
I/O pin for Buzzer Output Frequency Generator (P0.7, BUZ)  
Timing Tests in High-Speed Mode  
Watch timer overflow interrupt (IRQ 2, vector F6H) generation  
Watch timer control register, WTCON (set 1, bank 1, E1H, read/write)  
12-1  
WATCH TIMER  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
WATCH TIMER CONTROL REGISTER (WTCON)  
The watch timer control register, WTCON is used to select the input clock source, the watch timer interrupt time  
and Buzzer signal, to enable or disable the watch timer function. It is located in set 1, bank 1 at address E1H, and  
is read/write addressable using Register addressing mode.  
A reset clears WTCON to "00H". This disable the watch timer and select fx/128 as the watch timer clock.  
So, if you want to use the watch timer, you must write appropriate value to WTCON.  
Watch Timer Control Register (WTCON)  
E1H, Set 1, Bank 1, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
Watch timer interrupt pending bit:  
0 = Interrupt request is not pending  
(Clear pending bit when write"0")  
1 = Interrupt request is pending  
Watch timer clock selection bit:  
0 = Select main clock divided by 27 (fx/128)  
1 = Select sub clock (fxt)  
Watch timer INT Enable/Disable bit:  
0 = Disable watch timer INT  
1 = Enable watch timer INT  
Watch timer Enable/Disable bit:  
0 = Disable watch timer;  
clear frequency dividing circuits  
1 = Enable watch timer  
Buzzer signal selection bits:  
00 = 0.5 kHz  
Watch timer speed selection bits:  
00 = Set watch timer interrupt to 1 s  
01 = Set watch timer interrupt to 0.5 s  
10 = Set watch timer interrupt to 0.25 s  
11 = Set watch timer interrupt to 3.91 ms  
01 = 1 kHz  
10 = 2 kHz  
11 = 4 kHz  
Figure 12-1. Watch Timer Control Register (WTCON)  
12-2  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
WATCH TIMER CIRCUIT DIASGRAM  
WATCH TIMER  
WTCON.7  
WTCON.6  
WT INT Enable  
BUZ (P0.7)  
WTINT  
WTCON.6  
WTCON.5  
WTCON.4  
WTCON.3  
WTCON.2  
WTCON.1  
MUX  
8
f
f
W/64 (0.5 kHz)  
/32 (1 kHz)  
/16 (2 kHz)  
W/8 (4 kHz)  
fW  
W
f
Enable/Disable  
Selector  
Circuit  
WTCON.0  
WTCON.0  
(Pending Bit)  
f
W
/27  
/213  
/214  
/215  
f
W
Frequency  
Dividing  
Circuit  
Clock  
Selector  
f
W
fW  
f
W
(1 Hz)  
LCD = 2048 Hz  
32.768 kHz  
f
fxt fx/128  
f
X
= Main clock (where fx = 4.19 MHz)  
fxt = Sub clock (32.768 kHz)  
= Watch timer frequency  
f
W
Figure 12-2. Watch Timer Circuit Diagram  
12-3  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
LCD CONTROLLER/DRIVER  
13 LCD CONTROLLER/DRIVER  
OVERVIEW  
The S3C8275X/C8278X/C8274X microcontroller can directly drive an up-to-128-dot (32 segments x 4 commons)  
LCD panel. Its LCD block has the following components:  
LCD controller/driver  
Display RAM (00H0FH of page 2) for storing display data  
32 segment output pins (SEG0SEG31)  
4 common output pins (COM0COM3)  
Three LCD operating power supply pins (VLC0VLC2  
)
LCD bias by Internal/External register  
The LCD control register, LCON, is used to turn the LCD display on or off, to select LCD clock frequency, to  
select bias and duty, and switch the current to the dividing resistor for the LCD display. Data written to the LCD  
display RAM can be automatically transferred to the segment signal pins without program control.  
When a sub clock is selected as the LCD clock source, the LCD display is enabled even in main clock stop or idle  
mode.  
V
LC0-VLC2  
3
4
LCD  
Controller/  
Driver  
COM0-COM3  
SEG0-SEG31  
8
32  
Figure 13-1. LCD Function Diagram  
13-1  
LCD CONTROLLER/DRIVER  
LCD CIRCUIT DIAGRAM  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
SEG31/P2.0  
Port  
Latch  
SEG/Port  
Driver  
SEG16/P3.7  
SEG15/P4.0  
SEG0/P5.7  
LCD  
Display  
RAM  
COM3/P6.3  
COM2/P6.2  
(200H-20FH)  
COM/Port  
Driver  
f
LCD  
COM0/P6.0  
Timing  
Controller  
LCON  
VLC0  
VLC1  
VLC2  
LCD  
Voltage  
Controller  
Figure 13-2. LCD Circuit Diagram  
13-2  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
LCD RAM ADDRESS AREA  
LCD CONTROLLER/DRIVER  
RAM addresses of page 2 are used as LCD data memory. When the bit value of a display segment is "1", the  
LCD display is turned on; when the bit value is "0", the display is turned off.  
Display RAM data are sent out through segment pins SEG0SEG31 using a direct memory access (DMA)  
method that is synchronized with the fLCD signal. RAM addresses in this location that are not used for LCD  
display can be allocated to general-purpose use.  
b0 b4 b0 b4 b0 b4 b0 b4 b0 b4  
b1 b5 b1 b5 b1 b5 b1 b5 b1 b5  
b2 b6 b2 b6 b2 b6 b2 b6 b2 b6  
b3 b7 b3 b7 b3 b7 b3 b7 b3 b7  
200H 201H 202H 203H 204H  
b0 b4 b0 b4 b0 b4  
b1 b5 b1 b5 b1 b5  
b2 b6 b2 b6 b2 b6  
b3 b7 b3 b7 b3 b7  
20DH 20EH 20FH  
COM0  
COM1  
COM2  
COM3  
Figure 13-3. LCD Display Data RAM Organization  
Table 13-1. LCD Clock Signal Frame Frequency  
LCDCK Frequency (fLCD  
)
Static  
1/2 Duty  
1/3 Duty  
1/4 Duty  
64 Hz  
128 Hz  
256Hz  
512 Hz  
64  
32  
64  
21  
43  
16  
32  
128  
256  
512  
128  
256  
85  
64  
171  
128  
13-3  
LCD CONTROLLER/DRIVER  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
LCD CONTROL REGISTER (LCON)  
A LCON is located in set 1, bank 1, at address E0H, and is read/write addressable using Register addressing  
mode. It has the following control functions.  
LCD duty and bias selection  
LCD clock selection  
LCD display control  
Internal/External LCD dividing resistors selection  
The LCON register is used to turn the LCD display on/off, to select duty and bias, to select LCD clock and control  
the flow of the current to the dividing in the LCD circuit. Following a RESET, all LCON values are cleared to "0".  
This turns off the LCD display, select 1/4 duty and 1/3 bias, select 64Hz for LCD clock, and Enable internal LCD  
dividing resistors.  
The LCD clock signal determines the frequency of COM signal scanning of each segment output. This is also  
referred as the LCD frame frequency. Since the LCD clock is generated by watch timer clock (fw). The watch  
timer should be enabled when the LCD display is turned on.  
LCD Control Register (LCON)  
E0H, Set 1, Bank 1, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
Internal LCD dividing register enable bit:  
0 = Enable internal LCD dividing resistors  
1 = Disable internal LCD dividing resistors  
LCD display control bit:  
0 = Turn display off  
(Turn off the P-Tr)  
1 = Turn display on  
(Turn on the P-Tr)  
LCD clock selection bits:  
00 = fw/29 (64 Hz)  
Not used for S3C8275X/C8278X/C8274X  
01 = fw/28 (128 Hz)  
10 = fw/27 (256 Hz)  
11 = fw/26 (512 Hz)  
LCD duty and bias selection bits:  
000 = 1/4 duty, 1/3 bias  
001 = 1/3 duty, 1/3 bias  
010 = 1/3 duty, 1/2 bias  
011 = 1/2 duty, 1/2 bias  
1xx = Static  
NOTES:  
1. "x" means don't care.  
2. When 1/2 bias is selected, the bias levels are set as VLC0, VLC1(VLC2), and VSS  
.
Figure 13-4. LCD Control Register (LCON)  
13-4  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
LCD VOLTAGE DIVIDING RESISTOR  
LCD CONTROLLER/DRIVER  
Static and 1/3 Bias  
1/2 Bias  
S3C8275X/C8278X/C8274X  
S3C8275X/C8278X/C8274X  
V
DD  
VDD  
LCON.0  
LCON.0  
LCON.7 = 0: Enable internal resistors  
LCON.7 = 0: Enable internal resistors  
V
V
V
LC0  
V
V
V
LC0  
R
R
LC1  
LC2  
LC1  
LC2  
R
R
R
R
VLCD  
VLCD  
VSS  
VSS  
Voltage Dividing Resistor Adjustment  
S3C8275X/C8278X/C8274X  
V
DD  
LCON.0  
LCON.7 = 1: Disable internal resistors  
V
V
V
LC0  
R'  
R'  
R'  
LC1  
LC2  
VLCD  
VSS  
NOTES:  
1. R = Internal LCD dividing resistors. The resistors can be disconnected by LCON.7.  
2. R' = External LCD dividing resistors.  
Figure 13-5. Internal Voltage Dividing Resistor Connection  
13-5  
LCD CONTROLLER/DRIVER  
COMMON (COM) SIGNALS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
The common signal output pin selection (COM pin selection) varies according to the selected duty cycle.  
In 1/4 duty mode, COM0-COM3 pins are selected  
In 1/3 duty mode, COM0-COM2 pins are selected  
In 1/2 duty mode, COM0-COM1 pins are selected  
SEGMENT (SEG) SIGNALS  
The 32 LCD segment signal pins are connected to corresponding display RAM locations at page 2. Bits of the  
display RAM are synchronized with the common signal output pins.  
When the bit value of a display RAM location is "1", a select signal is sent to the corresponding segment pin.  
When the display bit is "0", a 'no-select' signal to the corresponding segment pin.  
Select  
Non-Select  
FR  
1 Frame  
V
V
LC0  
SS  
COM  
SEG  
V
V
LC0  
SS  
V
V
LC0  
SS  
COM-SEG  
-VLC0  
Figure 13-6. Select/No-Select Signals in Static Display Mode  
13-6  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
LCD CONTROLLER/DRIVER  
Select  
Non-Select  
FR  
1 Frame  
V
V
V
LC 0  
LC1, 2  
ss  
COM  
SEG  
V
V
V
LC 0  
LC1, 2  
ss  
V
V
V
LC 0  
LC1, 2  
ss  
COM-SEG  
-VLC1, 2  
-VLC 0  
Figure 13-7. Select/No-Select Signal in 1/2 Duty, 1/2 Bias Display Mode  
Select  
Non-Select  
FR  
1 Frame  
VLC0  
V
VLC1  
VSLCS2  
COM  
VLC0  
V
VLC1  
VSLCS2  
SEG  
VLC0  
V
VLC1  
VSLCS2  
-V  
COM-SEG  
-VLC2  
-VLLCC01  
Figure 13-8. Select/No-Select Signal in 1/3 Duty, 1/3 Bias Display Mode  
13-7  
LCD CONTROLLER/DRIVER  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
0
1
2
3
0
1
2
3
SEG1.4 x C0  
FR  
1 Frame  
V
V
V
V
LC0  
LC1  
LC2  
SS  
COM0  
V
V
V
V
LC0  
LC1  
LC2  
SS  
COM1  
COM2  
COM3  
SEG0  
SEG1  
SEG0.1 x C1  
V
V
V
V
LC0  
LC1  
LC2  
SS  
V
V
V
V
LC0  
LC1  
LC2  
SS  
SEG0.3x C3
SEG1.7 x C3  
V
V
V
V
LC0  
LC1  
LC2  
SS  
V
V
V
V
LC0  
LC1  
LC2  
SS  
V
V
V
V
-VLC2  
-VLC1  
-VLC0  
LC0  
LC1  
LC2  
SS  
COM0  
-SEG0  
V
V
V
V
-VLC2  
-VLC1  
-VLC0  
LC0  
LC1  
LC2  
SS  
COM0  
-SEG1  
V
V
V
V
-VLC2  
-VLC1  
-VLC0  
LC0  
LC1  
LC2  
SS  
COM1  
-SEG0  
V
V
V
V
-VLC2  
-VLC1  
-VLC0  
LC0  
LC1  
LC2  
SS  
COM1  
-SEG1  
Figure 13-9. LCD Signals and Wave Forms Example in 1/4 Duty, 1/3 Bias Display Mode  
13-8  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
SERIAL I/O INTERFACE  
14 SERIAL I/O INTERFACE  
OVERVIEW  
Serial I/O modules, SIO can interface with various types of external device that require serial data transfer. The  
components of SIO function block are:  
8-bit control register (SIOCON)  
Clock selector logic  
8-bit data buffer (SIODATA)  
8-bit prescaler (SIOPS)  
3-bit serial clock counter  
Serial data I/O pins (SI, SO)  
Serial clock input/output pin (SCK)  
The SIO module can transmit or receive 8-bit serial data at a frequency determined by its corresponding control  
register settings. To ensure flexible data transmission rates, you can select an internal or external clock source.  
PROGRAMMING PROCEDURE  
To program the SIO module, follow these basic steps:  
1. Configure the I/O pins at port (SCK/SI/SO) by loading the appropriate value to the P1CONL register if  
necessary.  
2. Load an 8-bit value to the SIOCON control register to properly configure the serial I/O module. In this  
operation, SIOCON.2 must be set to "1" to enable the data shifter.  
3. For interrupt generation, set the serial I/O interrupt enable bit (SIOCON) to "1".  
4. When you transmit data to the serial buffer, write data to SIODATA and set SIOCON.3 to 1, the shift  
operation starts.  
5. When the shift operation (transmit/receive) is completed, the SIO pending bit (SIOCON.0) are set to "1" and  
SIO interrupt request is generated.  
14-1  
SERIAL I/O INTERFACE  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
SIO CONTROL REGISTERS (SIOCON)  
The control register for serial I/O interface module, SIOCON, is located at E1H in set 1, bank 0. It has the control  
setting for SIO module.  
Clock source selection (internal or external) for shift clock  
Interrupt enable  
Edge selection for shift operation  
Clear 3-bit counter and start shift operation  
Shift operation (transmit) enable  
Mode selection (transmit/receive or receive-only)  
Data direction selection (MSB first or LSB first)  
A reset clears the SIOCON value to "00H". This configures the corresponding module with an internal clock  
source at the SCK, selects receive-only operating mode, and clears the 3-bit counter. The data shift operation  
and the interrupt are disabled. The selected data direction is MSB-first.  
Serial I/O Module Control Register (SIOCON)  
E1H, Set 1, Bank 0, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
SIO interrupt pending bit:  
0 = No interrupt pending  
0 = Clear pending condition  
(when write)  
SIO shift clock selection bit:  
0 = Internal clock (P.S Clock)  
1 = External clock (SCK)  
1 = Interrupt is pending  
Data direction control bit:  
0 = MSB-first mode  
1 = LSB-first mode  
SIO interrupt enable bit:  
0 = Disable SIO interrupt  
1 = Enable SIO interrupt  
SIO mode selection bit:  
0 = Receive only mode  
1 = Transmit/receive mode  
SIO shift operation enable bit:  
0 = Disable shifter and clock counter  
1 = Enable shifter and clock counter  
Shift clock edge selection bit:  
SIO counter clear and shift start bit:  
0 = No action  
1 = Clear 3-bit counter and start shifting  
0 = T  
1 = T  
X
at falling edges, Rx at rising edges  
at rising edges, Rx at falling edges  
X
Figure 14-1. Serial I/O Module Control Register (SIOCON)  
14-2  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
SIO PRE-SCALER REGISTER (SIOPS)  
SERIAL I/O INTERFACE  
The prescaler register for serial I/O interface module, SIOPS, is located at E3H in set 1, bank 0.  
The value stored in the SIO pre-scaler register, SIOPS, lets you determine the SIO clock rate (baud rate) as  
follows:  
Baud rate = Input clock (fxx/4)/(Prescaler value + 1), or SCK input clock.  
SIO Pre-scaler Register (SIOPS)  
E3H, Set 1, Bank 0, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
Baud rate = (fXX/4)/(SIOPS + 1)  
Figure 14-2. SIO Prescaler Register (SIOPS)  
SIO BLOCK DIAGRAM  
SIO INT  
3-Bit Counter  
SIOCON.0  
Pending  
Clear  
CLK  
SIOCON.1  
(Interrupt Enable)  
SIOCON.3  
SIOCON.7  
SIOCON.4  
(Edge Select)  
SIOCON.2  
(Shift Enable)  
SIOCON.5  
(Mode Select)  
M
U
X
SCK  
fxx/2  
SIOPS (E3H, set 1, bank 0)  
8-bit P.S. 1/2  
CLK  
8-Bit SIO Shift Buffer  
SO  
(SIODATA, E2H, set 1, bank 0)  
SIOCON.6  
(LSB/MSB First  
Mode Select)  
8
SI  
Data Bus  
Figure 14-3. SIO Functional Block Diagram  
14-3  
SERIAL I/O INTERFACE  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
SERIAL I/O TIMING DIAGRAM (SIO)  
SCK  
SI  
DI7  
DI6  
DI5  
DI4  
DI3  
DI2  
DI1  
DI0  
SO  
DO7  
DO6  
DO5  
DO4  
DO3  
DO2  
DO1  
DO0  
Transmit  
Complete  
SIO INT  
Set SIOCON.3  
Figure 14-4. Serial I/O Timing in Transmit/Receive Mode (Tx at falling, SIOCON.4 = 0)  
SCK  
DI7  
DI6  
DI5  
DI4  
DI3  
DI2  
DI1  
DI0  
SI  
SO  
DO7  
DO6  
DO5  
DO4  
DO3  
DO2  
DO1  
DO0  
Transmit  
Complete  
SIO INT  
Set SIOCON.3  
Figure 14-5. Serial I/O Timing in Transmit/Receive Mode (Tx at rising, SIOCON.4 = 1)  
14-4  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
BATTERY LEVEL DETECTOR  
15 BATTERY LEVEL DETECTOR  
OVERVIEW  
The S3C8275X/C8278X/C8274X micro-controller has a built-in BLD (Battery Level Detector) circuit which allows  
detection of power voltage drop or external input level through software. Turning the BLD operation on and off can  
be controlled by software. Because the IC consumes a large amount of current during BLD operation. It is  
recommended that the BLD operation should be kept OFF unless it is necessary. Also the BLD criteria voltage  
can be set by the software. The criteria voltage can be set by matching to one of the 3 kinds of voltage below that  
can be used.  
2.2 V, 2.4 V or 2.8 V (VDD reference voltage), or external input level (External reference voltage)  
The BLD block works only when BLDCON.3 is set. If VDD level is lower than the reference voltage selected with  
BLDCON.2–.0, BLDCON.4 will be set. If VDD level is higher, BLDCON.4 will be cleared. When users need to  
minimize current consumption, do not operate the BLD block.  
V
DD Pin  
Battery  
Level  
Detector  
f
BLD  
BLDCON.4  
BLD Out  
BLDCON.5  
MUX  
BLDCON.3  
BLD Run  
V
BLDREF/P2.0  
Battery  
Level  
Setting  
P2CONL.1-.0  
BLDCON.2-0  
Set the Level  
ExtRef Input  
Enable  
Figure 15-1. Block Diagram for Voltage Level Detect  
15-1  
BATTERY LEVEL DETECTOR  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
BATTERY LEVEL DETECTOR CONTROL REGISTER (BLDCON)  
The bit 3 of BLDCON controls to run or disable the operation of Battery Level Detector. Basically this VBLD is set  
as 2.2V by system reset and it can be changed in 3 kinds voltages by selecting Battery Level Detector Control  
Register (BLDCON). When you write 3-bit data value to BLDCON, an established resistor string is selected and  
the VBLD is fixed in accordance with this resistor. Table 15-1 shows specific VBLD of 3 levels.  
Resistor String  
Battery Level Detector Control Register  
F4H, Set 1, Bank 1, R/W, Reset : 00H  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
Not used  
R
BLD  
V
IN  
+
Mux  
Comparator  
BLD OUT  
V
REF  
Bias  
V
BAT  
V
BLDREF  
f
BLD  
BANDGAP  
BLD Enable/Disable  
P2CONL.1-.0  
NOTES:  
1. The reset value of BLDCON is #00H.  
2. REF is about 1 volt.  
V
Figure 15-2. Battery Level Detect Circuit and Control Register  
Table 15-1. BLDCON Value and Detection Level  
VBLD  
BLDCON .2.0  
0
1
0
0
0
1
0
1
1
2.2 V  
2.4 V  
2.8 V  
Other values  
Not available  
15-2  
S3F8275X  
EMBEDDED FLASH MEMORY INTERFACE  
16 EMBEDDED FLASH MEMORY INTERFACE  
OVERVIEW  
This chapter is only for the S3F8275X. The S3F8275X has an on-chip full-flash memory internally instead of  
masked ROM. The flash memory is accessed by "LDC" instruction and the type of sector erase and a byte  
programmable flash, a user can program the data in the flash memory area any time you want. The S3F8275X's  
embedded 16K-byte memory has two operating features:  
User program mode: S3F8275X only  
Tool program mode: Refer to the chapter 19. S3F8275X/F8278X/F8274X FLASH MCU.  
16-1  
EMBEDDED FLASH MEMORY INTERFACE  
S3F8275X  
USER PROGRAM MODE  
This mode supports sector erase, byte programming, byte read and one protection mode (Hard lock protection).  
The read protection mode is available only in Tool Program mode. So in order to make a chip into read protection,  
you need to select a read protection option when you program an initial your code to a chip by using Tool Program  
mode by using a programming tool.  
The S3F8275X has the pumping circuit internally. Therefore, 12.5V into VPP (test) pin is not needed. To program  
a flash memory in this mode several control registers will be used. There are four kind functions– programming,  
reading, sector erase, hard lock protection.  
FLASH MEMORY CONTROL REGISTERS (USER PROGRAM MODE)  
Flash Memory Control Register  
FMCON register is available only in user program mode to select the Flash Memory operation mode; sector erase,  
byte programming, and to make the flash memory into a hard lock protection.  
Flash Memory Control Register (FMCON)  
F0H, Set 1, Bank 1, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
Flash operation start bit:  
0 = Operation stop  
1 = Operation start  
Flash memory mode selection bits:  
0101 = Programming mode  
1010 = Sector erase mode  
0110 = Hard lock mode  
(This bit will be cleared automatically  
just after the corresponding operation  
completed).  
others = Not available  
Not used for S3F8275X  
Sector erase status bit:  
0 = Success sector erase  
1 = Fail sector erase  
Figure 16-1. Flash Memory Control Register (FMCON)  
The bit 0 of FMCON register (FMCON.0) is a start bit for Erase and Hard Lock operation mode. Therefore,  
operation of Erase and Hard Lock mode is activated when you set FMCON.0 to "1". Also you should wait a time of  
Erase (Sector erase) or Hard lock to complete it's operation before a byte programming or a byte read of same  
sector area by using "LDC" instruction. When you read or program a byte data from or into flash memory, this bit  
is not needed to manipulate.  
The sector erase status bit is read only. If an interrupt is requested during the operation of "Sector erase", the  
operation of "Sector Erase" is discontinued, and the interrupt is served by CPU. Therefore, the sector erase status  
bit should be checked after executing "Sector Erase". The "Sector Erase" operation is success if the bit is logic  
"0", and is failure if the bit is logic "1".  
NOTE: When the ID code, "A5H", is written to the FMUSR register. A mode of sector erase, user program, and hard lock may  
be executed unfortunately. So, It should be careful of the above situation.  
16-2  
S3F8275X  
EMBEDDED FLASH MEMORY INTERFACE  
Flash Memory User Programming Enable Register  
The FMUSR register is used for a safety operation of the flash memory. This register will protect undesired erase  
or program operation from malfunctioning of CPU caused by an electrical noise. After reset, the user-programming  
mode is disabled, because the value of FMUSR is "00000000B" by reset operation. If necessary to operate the  
flash memory, you can use the user programming mode by setting the value of FMUSR to "10100101B". The  
other value of "10100101b", user program mode is disabled.  
Flash Memory User Programming Enable Register (FMUSR)  
F1H, Set 1, Bank 1, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
Flash memory user programming enable bits:  
10100101: Enable user programming mode  
Other values: Disable user programming mode  
Figure 16-2. Flash Memory User Programming Enable Register (FMUSR)  
16-3  
EMBEDDED FLASH MEMORY INTERFACE  
Flash Memory Sector Address Registers  
S3F8275X  
There are two sector address registers for addressing a sector to be erased. The FMSECL (Flash Memory Sector  
Address Register Low Byte) indicates the low byte of sector address and FMSECH (Flash Memory Sector  
Address Register High Byte) indicates the high byte of sector address.  
The FMSECH is needed for S3F8275X because it has 128 sectors, respectively. One sector consist of 128-bytes.  
Each sector's address starts XX00H or XX80H, that is, a base address of sector is XX00H or XX80H. So FMSECL  
register 6-0 don't mean whether the value is ‘1' or '0'. We recommend that the simplest way is to load sector base  
address into FMSECH and FMSECL register.  
When programming the flash memory, you should write data after loading sector base address located in the  
target address to write data into FMSECH and FMSECL register. If the next operation is also to write data, you  
should check whether next address is located in the same sector or not. It case of other sectors, you must load  
sector address to FMSECH and FMSECL register according to the sector.  
Flash Memory Sector Address Register, High Byte (FMSECH)  
F2H, Set 1, Bank 1, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
Flash Memory Setor Address (High Byte)  
NOTE:  
The high-byte flash memory sector address pointer  
value is the higher eight bits of the 16-bit pointer address.  
Figure 16-3. Flash Memory Sector Address Register, High Byte (FMSECH)  
Flash Memory Sector Address Register, Low Byte (FMSECL)  
F3H, Set 1, Bank 1, R/W  
MSB  
.7  
.6  
.5  
.4  
.3  
.2  
.1  
.0  
LSB  
Don't care  
Flash Memory Sector Address (Low Byte)  
NOTE:  
The low-byte flash memory sector address pointer  
value is the lower eight bits of the 16-bit pointer address.  
Figure 16-4. Flash Memory Sector Address Register, Low Byte (FMSECL)  
16-4  
S3F8275X  
EMBEDDED FLASH MEMORY INTERFACE  
ISPTM (ON-BOARD PROGRAMMING) SECTOR  
ISPTM sectors located in program memory area can store on board program software (boot program code for  
upgrading application code by interfacing with I/O pin). The ISPTM sectors can not be erased or programmed by  
LDC instruction for the safety of On Board Program software.  
The ISP sectors are available only when the ISP enable/disable bit is set 0, that is, enable ISP at the Smart  
Option. If you don't like to use ISP sector, this area can be used as a normal program memory (can be erased or  
programmed by LDC instruction) by setting ISP disable bit ("1") at the Smart Option. Even if ISP sector is  
selected, ISP sector can be erased or programmed in the Tool Program mode, by Serial programming tools. The  
size of ISP sector can be varied by settings of Smart Option. You can choose appropriate ISP sector size  
according to the size of On Board Program software.  
(Decimal)  
16,383  
(HEX)  
3FFFH  
16K-bytes  
Internal Program  
Memory Area  
8FFH  
FFH  
Available  
ISP Sector Area  
255  
Interrupt Vector Area  
Smart Option Area  
3FH  
3CH  
0
00H  
S3F8275X  
Figure 16-5. Program Memory Address Space  
16-5  
EMBEDDED FLASH MEMORY INTERFACE  
S3F8275X  
Table 16-1. ISP Sector Size  
Smart Option(003EH) ISP Size Selection Bit  
Area of ISP Sector  
ISP Sector Size  
Bit 2  
Bit 1  
Bit 0  
1
0
0
0
0
x
0
0
1
1
x
0
1
0
1
0
100H – 1FFH (256 byte)  
100H – 2FFH (512 byte)  
100H – 4FFH (1024 byte)  
100H – 8FFH (2048 byte)  
256 Bytes  
512 Bytes  
1024 Bytes  
2048 Bytes  
NOTE: The area of the ISP sector selected by Smart Option bit (003EH.2 003EH.0) can not be erased and programmed  
by LDC instruction in user program mode.  
ISP Reset Vector and ISP Sector Size  
If you use ISP sectors by setting the ISP enable/disable bit to "0" and the Reset Vector Selection bit to "0" at the  
Smart Option, you can choose the reset vector address of CPU as shown in Table 16-3 by setting the ISP Reset  
Vector Address Selection bits.  
Table 16-2. Reset Vector Address  
Smart Option (003EH) ISP Reset  
Vector Address Selection Bit  
Reset Vector  
Address After POR  
Usable Area for ISP  
Sector  
ISP Sector Size  
Bit 7  
Bit 6  
Bit 5  
1
0
0
0
0
x
0
0
1
1
x
0
1
0
1
0100H  
0200H  
0300H  
0500H  
0900H  
256 Bytes  
512 Bytes  
1024 Bytes  
2048 Bytes  
100H 1FFH  
100H 2FFH  
100H 4FFH  
100H 8FFH  
NOTE: The selection of the ISP reset vector address by smart option (003EH.7 – 003EH.5) is not dependent of the  
selection of ISP sector size by smart option (003EH.2 – 003EH.0).  
16-6  
S3F8275X  
EMBEDDED FLASH MEMORY INTERFACE  
SECTOR ERASE  
User can erase a flash memory partially by using sector erase function only in User Program Mode. The only unit  
of flash memory to be erased and programmed in User Program Mode is called sector.  
The program memory of S3F8275X is divided into 128 sectors for unit of erase and programming. Every sector  
has all 128-byte sizes of program memory areas. So each sector should be erased first to program a new data  
(byte) into a sector. Minimum 10ms delay time for erase is required after setting sector address and triggering  
erase start bit (FMCON.0). Sector Erase is not supported in Tool Program Modes (MDS mode tool or  
Programming tool).  
3FFFH  
Sector 127 (128 Byte)  
3F7FH  
Sector 126 (128 Byte)  
3EFFH  
1FFFH  
Sector 63 (128 Byte)  
1F7FH  
05FFH  
Sector 11 (128 Byte)  
057FH  
Sector 10 (128 Byte)  
0500H  
04FFH  
Sector 0-9  
(128 byte x 10)  
0000H  
S3F8275X  
Figure 16-6. Sector Configurations in User Program Mode  
16-7  
EMBEDDED FLASH MEMORY INTERFACE  
S3F8275X  
The Sector Erase Procedure in User Program Mode  
1. Set Flash Memory User Programming Enable Register (FMUSR) to "10100101B".  
2. Set Flash Memory Sector Address Register (FMSECH/FMSECL).  
3. Check user’s ID code (written by user).  
4. Set Flash Memory Control Register (FMCON) to "10100001B".  
5. Set Flash Memory User Programming Enable Register (FMUSR) to "00000000B"  
6. Check the "sector erase status bit" whether "sector erase" is success or not.  
PROGRAMMING TIP Sector Erase  
SB1  
reErase:  
LD  
LD  
LD  
CP  
FMUSR,#0A5H  
FMSECH,#10H  
FMSECL,#00H  
; User program mode enable  
; Set sector address (1000H 107FH)  
UserID_Code,#User_value; Check user’s ID code (written by user)  
; User_value is any value by user  
JR  
LD  
NE,Not_ID_Code  
FMCON,#10100001B  
; If not equal, jump to Not_ID_Code  
; Start sector erase  
NOP  
NOP  
LD  
; Dummy instruction, this instruction must be needed  
; Dummy instruction, this instruction must be needed  
; User program mode disable  
FMUSR,#0  
TM  
JR  
FMCON,#00001000B  
NZ,reErase  
; Check "Sector erase status bit"  
; Jump to reErase if fail  
Not_ID_Code:  
SB1  
LD  
FMUSR,#0  
; User Program mode disable  
16-8  
S3F8275X  
EMBEDDED FLASH MEMORY INTERFACE  
PROGRAMMING  
A flash memory is programmed in one byte unit after sector erase. And for programming safety's sake, must set  
FMSECH and FMSECL to flash memory sector value.  
The write operation of programming starts by 'LDC' instruction.  
You can write until 128byte, because this flash sector's limits is 128byte.  
So if you written 128byte, must reset FMSECH and FMSECL.  
The Program Procedure in User program Mode  
1. Must erase sector before programming.  
2. Set Flash Memory User Programming Enable Register (FMUSR) to “10100101B”.  
3. Set Flash Memory Sector Register (FMSECH, FMSECL) to sector value of write address.  
4. Load a flash memory upper address into upper register of pair working register.  
5. Load a flash memory lower address into lower register of pair working register.  
6. Load a transmission data into a working register.  
7. Check user’s ID code (written by user)  
8. Set Flash Memory Control Register (FMCON) to “01010001B”.  
9. Load transmission data to flash memory location area on ‘LDC’ instruction by indirectly addressing mode  
10. Set Flash Memory User Programming Enable Register (FMUSR) to “00000000B”.  
16-9  
EMBEDDED FLASH MEMORY INTERFACE  
S3F8275X  
PROGRAMMING TIP Program  
SB1  
LD  
LD  
LD  
LD  
LD  
LD  
CP  
FMUSR,#0A5H  
; User Program mode enable  
FMSECH,#17H  
FMSECL,#80H  
R2,#17H  
R3,#84H  
R4,#78H  
; Set sector address (1780H17FFH)  
; Set a ROM address in the same sector 1780H17FFH  
; Temporary data  
UserID_Code,#User_value ; Check user’s ID code (written by user)  
; User_value is any value by user  
JR  
LD  
LDC  
NOP  
LD  
NE,Not_ID_Code  
FMCON,#01010001B  
@RR2,R4  
; If not equal, jump to Not_ID_Code  
; Start program  
; Write the data to a address of same sector(1784H)  
; Dummy Instruction, This instruction must be needed  
; User Program mode disable  
FMUSR,#0  
FMUSR,#0  
Not_ID_Code:  
SB1  
LD  
; User Program mode disable  
16-10  
S3F8275X  
EMBEDDED FLASH MEMORY INTERFACE  
READING  
The read operation of programming starts by 'LDC' instruction.  
The Reading Procedure in User Program Mode  
1. Load a flash memory upper address into upper register of pair working register.  
2. Load a flash memory lower address into lower register of pair working register.  
3. Load receive data from flash memory location area on 'LDC' instruction by indirectly addressing mode.  
PROGRAMMING TIP Reading  
LD  
R2,#3H  
R3,#0  
; Load flash memory upper address  
; To upper of pair working register  
; Load flash memory lower address  
; To lower pair working register  
; Read data from flash memory location  
; (Between 300H and 3FFH)  
LD  
LOOP:  
LDC  
R0,@RR2  
INC  
CP  
JP  
R3  
R3,#0H  
NZ,LOOP  
16-11  
EMBEDDED FLASH MEMORY INTERFACE  
S3F8275X  
HARD LOCK PROTECTION  
User can set Hard Lock Protection by write ‘0110’ in FMCON.74. If this function is enabled, the user cannot write  
or erase the data in a flash memory area. This protection can be released by the chip erase execution (in the tool  
program mode).  
In terms of user program mode, the procedure of setting Hard Lock Protection is following that. Whereas in tool  
mode the manufacturer of serial tool writer could support Hardware Protection. Please refer to the manual of serial  
program writer tool provided by the manufacturer.  
The Hard Lock Protection Procedure in User program Mode  
1. Set Flash Memory User Programming Enable Register (FMUSR) to “10100101B”.  
2. Check user’s ID code (written by user)  
3. Set Flash Memory Control Register (FMCON) to “01100001B”.  
4. Set Flash Memory User Programming Enable Register (FMUSR) to “00000000B”.  
PROGRAMMING TIP Hard Lock Protection  
SB1  
LD  
CP  
FMUSR,#0A5H  
; User Program mode enable  
UserID_Code,#User_value ; Check user’s ID code (written by user)  
; User_value is any value by user  
JR  
LD  
NE,Not_ID_Code  
FMCON,#01100001B  
; If not equal, jump to Not_ID_Code  
; Hard Lock mode set & start  
NOP  
LD  
; Dummy Instruction, This instruction must be needed  
; User Program mode disable  
FMUSR,#0  
Not_ID_Code:  
SB1  
LD  
FMUSR,#0  
; User Program mode disable  
16-12  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
ELECTRICAL DATA  
17 ELECTRICAL DATA  
OVERVIEW  
In this chapter, S3C8275X/C8278X/C8274X electrical characteristics are presented in tables and graphs. The  
information is arranged in the following order:  
Absolute maximum ratings  
D.C. electrical characteristics  
Data retention supply voltage in Stop mode  
Stop mode release timing when initiated by an external interrupt  
Stop mode release timing when initiated by a RESET  
I/O capacitance  
A.C. electrical characteristics  
Input timing for external interrupts  
Input timing for RESET  
Serial data transfer timing  
BLD electrical characteristics  
LVR electrical characteristics  
Oscillation characteristics  
Oscillation stabilization time  
Operating voltage range  
A.C. electrical characteristics for Internal flash ROM  
17-1  
ELECTRICAL DATA  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Table 17-1. Absolute Maximum Ratings  
°
(TA = 25 C)  
Parameter  
Symbol  
Conditions  
Rating  
Unit  
VDD  
Supply voltage  
Input voltage  
V
0.3 to + 4.6  
VI  
Ports 0–6  
V
V
0.3 to VDD + 0.3  
VO  
IOH  
Output voltage  
Output current High  
0.3 to  
VDD + 0.3  
One I/O pin active  
mA  
15  
60  
All I/O pins active  
One I/O pin active  
IOL  
Output current Low  
+ 30 (Peak value)  
mA  
Total pin current for ports  
+ 100 (Peak value)  
°
TA  
Operating temperature  
Storage temperature  
25 to + 85  
C
°
TSTG  
65 to + 150  
C
Table 17-2. D.C. Electrical Characteristics  
°
°
(TA  
=
25 C to + 85 C, VDD  
=
2.0 V to 3.6 V)  
Parameter  
Symbol  
Conditions  
Min  
Typ  
Max  
Unit  
VDD  
Operating voltage  
Input high voltage  
2.0  
3.6  
V
fx = 0.4 4.2MHz, fxt = 32.8kHz  
2.5  
3.6  
VDD  
fx = 0.4 8.0MHz  
VIH1  
VIH2  
VIH3  
VIL1  
VIL2  
VIL3  
VOH  
All input pins except for V , V  
0.7 VDD  
0.8 VDD  
VDD – 0.1  
V
V
IH2 IH3  
VDD  
Ports 0-1, nRESET  
XIN, XOUT and XTIN, XTOUT  
All input pins except for V , V  
VDD  
0.3 VDD  
0.2 VDD  
Input low voltage  
IL2 IL3  
Ports 0-1, nRESET  
XIN, XOUT, XTIN, XTOUT  
VDD = 2.7 to 3.6 V;  
0.1  
VDD – 1.0  
Output high  
voltage  
V
V
All output ports; IOH  
=
1 mA  
VOL1  
VDD = 2.7 to 3.6 V  
IOL = 15mA  
Output low  
voltage  
1.0  
1.0  
Ports 0-1  
VOL2  
VDD = 2.7 to 3.6 V  
IOL = 10mA  
V
All output ports except for VOL1  
ILIH1  
V = V  
Input high leakage  
current  
3
µA  
I
DD  
All input pins except for ILIH2  
ILIH2  
VI = VDD  
20  
XIN, XOUT, XTIN, XTOUT  
17-2  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
ELECTRICAL DATA  
Table 17-2. D.C. Electrical Characteristics (Continued)  
°
°
(TA  
=
25 C to + 85 C, VDD  
=
2.0 V to 3.6 V)  
Parameter  
Input low  
leakage current  
Symbol  
Conditions  
Min  
Typ  
Max  
Unit  
ILIL1  
V = 0 V;  
I
–3  
µA  
All input pins except nRESET,  
ILIL2  
ILIL2  
ILOH  
ILOL  
RL1  
V = 0 V;  
I
XIN, XOUT, XTIN, XTOUT  
–20  
3
VO = VDD  
Output high  
leakage current  
All output pins  
VO = 0 V  
Output low  
leakage current  
–3  
All output pins  
°
Pull-up resistors  
40  
70  
100  
kΩ  
kΩ  
VI = 0 V; VDD = 3V, TA = 25 C  
Ports 0–6  
°
RL2  
220  
600  
360  
1700  
4000  
500  
3000  
8000  
VI = 0 V; VDD = 3V, TA = 25 C  
nRESET  
ROSC1  
Oscillator feed  
back resistors  
VDD = 3 V, TA = 25 °C  
XIN = VDD, XOUT = 0V  
ROSC2  
2000  
VDD = 3 V, TA = 25 °C  
XTIN = VDD, XTOUT = 0 V  
RLCD  
VDC  
LCD voltage  
dividing resistor  
60  
110  
160  
120  
TA = 25 °C  
kΩ  
V
mV  
15 µA per common pin  
15 µA per common pin  
-COMi⏐  
LCD  
voltage drop  
(i = 0-3)  
V
VDS  
120  
LCD-SEGx⏐  
voltage drop  
(x = 0–31)  
VLC1  
VDD 2.7 V to 3.6 V, 1/3 bias  
=
LCD clock = 0Hz, VLC0 = VDD  
2/3VDD–0.2 2/3VDD 2/3VDD+ 0.2  
1/3VDD–0.2 1/3VDD 1/3VDD+ 0.2  
Middle output  
voltage (1)  
V
VLC2  
NOTE: It is middle output voltage when the V  
pin is opened.  
LC0  
17-3  
ELECTRICAL DATA  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Table 17-2. D.C. Electrical Characteristics (Concluded)  
°
°
(TA  
=
25 C to + 85 C, VDD  
=
2.0 V to 3.6 V)  
Unit  
Parameter  
Symbol  
Conditions  
Min  
Typ  
Max  
(2)  
Supply current (1)  
IDD1  
Run mode:  
DD = 3.3 V ± 0.3 V  
8.0 MHz  
3.0  
6.0  
mA  
V
Crystal oscillator  
C1 = C2 = 22pF  
4.0 MHz  
8.0 MHz  
1.5  
0.5  
3.0  
1.6  
(2)  
Idle mode:  
IDD2  
VDD = 3.3 V ± 0.3 V  
Crystal oscillator  
C1 = C2 = 22pF  
4.0 MHz  
0.4  
1.2  
(3)  
12.0  
25.0  
Run mode: VDD = 3.3 V ± 0.3 V,  
µA  
IDD3  
32 kHz crystal oscillator  
°
TA = 25 C, OSCCON.7=1  
(3)  
2.0  
4.0  
Idle mode: VDD = 3.3 V ± 0.3 V,  
IDD4  
32 kHz crystal oscillator  
°
TA = 25 C, OSCCON.7=1  
(4)  
°
Stop mode;  
0.2  
2.0  
10  
IDD5  
TA = 25 C  
VDD = 3.3 V ± 0.3 V  
°
TA = 25 C ~  
°
+85 C  
NOTES:  
1. Supply current does not include current drawn through internal pull-up resistors, LCD voltage dividing resistors, the  
LVR block, and external output current loads.  
2.  
3.  
4.  
I
I
I
and I  
include power consumption for sub clock oscillation.  
DD1  
DD3  
DD5  
DD2  
and I  
are current when main clock oscillation stops and the sub clock is used (OSCCON.7=1).  
DD4  
is current when main clock and sub clock oscillation stops.  
5. Every values in this table is measured when bits 4-3 of the system clock control register (CLKCON.4-.3) is set to 11B.  
17-4  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
ELECTRICAL DATA  
Table 17-3. Data Retention Supply Voltage in Stop Mode  
°
°
(TA  
=
25 C to + 85 C)  
Parameter  
Symbol  
Conditions  
Min  
Typ  
Max  
Unit  
VDDDR  
Data retention supply  
voltage  
2.0  
3.6  
V
°
IDDDR  
Data retention supply  
current  
1
µA  
Stop mode, TA = 25 C  
VDDDR = 2.0 V  
Disable LVR block  
Idle Mode  
(Basic Timer Active)  
Stop Mode  
Normal  
Operating Mode  
Data Retention Mode  
VDD  
VDDDR  
Execution of  
STOP Instruction  
0.8 VDD  
t
WAIT  
NOTE:  
tWAIT is the same as 16 x 1/BT clock.  
Figure 17-1. Stop Mode Release Timing When Initiated by an External Interrupt  
17-5  
ELECTRICAL DATA  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Oscillation  
Stabilization  
TIme  
RESET  
Occurs  
Stop Mode  
Normal  
Operating Mode  
Data Retention Mode  
V
DD  
V
DDDR  
Execution of  
STOP Instrction  
nRESET  
0.8 VDD  
0.2 VDD  
t
WAIT  
NOTE:  
tWAIT is the same as 16 × 1/BT clock.  
Figure 17-2. Stop Mode Release Timing When Initiated by a RESET  
Table 17-4. Input/Output Capacitance  
°
°
(TA  
=
25 C ~ + 85 C, VDD = 0 V)  
Parameter  
Input  
capacitance  
Symbol  
Conditions  
Min  
Typ  
Max  
Unit  
CIN  
f = 1 MHz; unmeasured pins  
are connected to VSS  
10  
pF  
COUT  
CIO  
Output  
capacitance  
I/O capacitance  
17-6  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
ELECTRICAL DATA  
Table 17-5. A.C. Electrical Characteristics  
25 C to + 85 C, VDD = 2.0 V to 3.6 V)  
°
°
(TA  
=
Parameter  
Symbol  
Conditions  
Min  
1,000  
Typ  
Max  
Unit  
tKCY  
SCK cycle time  
External SCK source  
Internal SCK source  
External SCK source  
Internal SCK source  
ns  
1,000  
tKH, tKL  
SCK high, low width  
500  
tKCY/250  
tSIK  
SI setup time to SCK high  
SI hold time to SCK high  
External SCK source  
Internal SCK source  
External SCK source  
250  
250  
400  
tKSI  
Internal SCK source  
External SCK source  
Internal SCK source  
All interrupt  
400  
tKSO  
Output delay for SCK to SO  
Interrupt input, High, Low width  
nRESET input Low width  
300  
250  
ns  
ns  
µs  
700  
tINTH  
500  
10  
,
VDD = 3 V  
tINTL  
tRSL  
Input  
VDD = 3 V  
t
INTL  
tINTH  
External  
Interrupt  
0.8 VDD  
0.2 VDD  
NOTE:  
The unit tCPU means one CPU clock period.  
Figure 17-3. Input Timing for External Interrupts  
17-7  
ELECTRICAL DATA  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
t
RSL  
nRESET  
0.2 VDD  
Figure 17-4. Input Timing for RESET  
t
KCY  
t
KL  
tKH  
SCK  
0.8VDD  
0.2VDD  
t
SIK  
t
KSI  
0.8VDD  
SI  
0.2VDD  
t
KSO  
SO  
Output Data  
Figure 17-5. Serial Data Transfer Timing  
17-8  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
ELECTRICAL DATA  
Table 17-6. Battery Level Detector Electrical Characteristics  
25 C, VDD = 2.0 V to 3.6 V)  
°
(TA  
=
Parameter  
Symbol  
Conditions  
Min  
Typ  
Max  
Unit  
VDDBLD  
Operating voltage of BLD  
Voltage of BLD  
2.0  
3.6  
V
VBLD  
BLDCON.2-.0 = 000b  
2.0  
2.2  
2.4  
BLDCON.2-.0 = 101b  
BLDCON.2-.0 = 011b  
VDD = 3.3 V  
2.15  
2.5  
2.4  
2.8  
70  
2.65  
3.1  
IBLD  
Current consumption  
120  
µA  
VDD = 2.2 V  
50  
10  
100  
100  
Hysteresis voltage of BLD  
BLD circuit response time  
BLDCON.2-0 = 000b,  
101b, 011b  
mV  
ms  
V  
TB  
Fw = 32.768 kHz  
1
Table 17-7. LVR (Low Voltage Reset) Electrical Characteristics  
°
(TA  
=
25 C)  
Parameter  
Symbol  
Conditions  
Min  
Typ  
Max  
Unit  
°
VLVR  
Voltage of LVR  
2.0  
2.2  
2.4  
V
TA = 25 C  
VDD voltage rising time  
VDD voltage off time  
tR  
10  
µs  
s
tOFF  
0.5  
Hysteresis voltage of LVR  
Current consumption  
10  
70  
100  
120  
mV  
µA  
V  
IDDPR  
VDD = 3.3 V  
NOTES:  
1. The current of LVR circuit is consumed when LVR is enabled by "Smart Option"  
2. Current consumed when low voltage reset circuit is provided internally.  
t
OFF  
tR  
V
DD  
0.9 VDD  
0.1 VDD  
Figure 17-6. LVR (Low Voltage Reset) Timing  
17-9  
ELECTRICAL DATA  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Table 17-8. Main Oscillation Characteristics  
°
°
85 C)  
(TA  
=
25 C to  
+
Oscillator  
Clock Configuration  
Parameter  
Test Condition  
Min  
Typ  
Max Units  
C1  
Crystal  
Main oscillation  
frequency  
0.4  
8
MHz  
2.5 V 3.6 V  
XIN  
XOUT  
0.4  
0.4  
4.2  
8
2.0 V 3.6 V  
2.5 V 3.6 V  
C1  
Ceramic  
oscillator  
Main oscillation  
frequency  
XIN  
XOUT  
0.4  
0.4  
4.2  
8
2.0 V 3.6 V  
2.5 V 3.6 V  
XIN input frequency  
External  
clock  
XIN  
XOUT  
0.4  
0.4  
4.2  
1
2.0 V 3.6 V  
RC  
oscillator  
Frequency  
3.3 V  
MHz  
XIN  
R
XOUT  
Table 17-9. Sub Oscillation Characteristics  
°
°
85 C)  
(TA  
=
25 C to  
+
Oscillator  
Clock Configuration  
Parameter  
Test Condition  
Min  
Typ  
Max Units  
C1  
Crystal  
Sub oscillation  
frequency  
32  
32.768  
35  
kHz  
2.0 V 3.6 V  
XTIN  
XTOUT  
V
REG  
104  
XTIN input  
frequency  
External  
clock  
32  
100  
2.0 V 3.6 V  
XTIN  
XTOUT  
17-10  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
ELECTRICAL DATA  
Table 17-10. Main Oscillation Stabilization Time  
25 C to + 85 C, VDD = 2.0 V to 3.6 V)  
Oscillator Test Condition  
Crystal  
°
°
(TA  
=
Min  
Typ  
Max  
40  
Unit  
ms  
fx > 1 MHz  
Oscillation stabilization occurs when VDD is  
Ceramic  
10  
ms  
equal to the minimum oscillator voltage  
range.  
XIN input high and low width (tXH, tXL  
)
External clock  
62.5  
1250  
ns  
1/fx  
t
XL  
tX  
XIN  
VDD-0.1 V  
0.1 V  
Figure 17-7. Clock Timing Measurement at XIN  
17-11  
ELECTRICAL DATA  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Table 17-11. Sub Oscillation Stabilization Time  
°
°
(TA  
=
25 C to + 85 C, VDD = 2.0 V to 3.6 V)  
Oscillator  
Crystal  
Test Condition  
Min  
Typ  
Max  
10  
Unit  
s
XTIN input high and low width (tXH, tXL  
)
External clock  
5
15  
µs  
1/fxt  
t
XTL  
tXTH  
XTIN  
VDD-0.1 V  
0.1 V  
Figure 17-8. Clock Timing Measurement at XTIN  
17-12  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
ELECTRICAL DATA  
Instruction Clock  
fx (Main/Sub oscillation frequency)  
2 MHz  
8 MHz  
1.05 MHz  
4.2 MHz  
6.25 kHz(main)/8.2 kHz(sub)  
1
400 kHz (main)/32.8 kHz(sub)  
2
3
4
2.5  
3.6  
Supply Voltage (V)  
Instruction Clock = 1/4n x oscillator frequency (n = 1, 2, 8, 16)  
Figure 17-9. Operating Voltage Range  
Table 17-12. A.C. Electrical Characteristics for Internal Flash ROM  
°
°
(TA  
=
25 C to + 85 C, VDD = 2.2 V to 3.6 V)  
Parameter  
Symbol  
Ftp  
Conditions  
Min  
30  
50  
10  
Typ  
Max  
Unit  
µs  
Programming time (1)  
Chip erasing time (2)  
Sector erasing time (3)  
Data access time  
Ftp1  
ms  
ms  
ns  
Ftp2  
FtRS  
25  
10,000(4)  
Number of writing/erasing  
FNwe  
Times  
NOTES:  
1. The programming time is the time during which one byte (8-bit) is programmed.  
2. The chip erasing time is the time during which all 16K byte block is erased.  
3. The sector erasing time is the time during which all 128 byte block is erased.  
4. Maximum number of writing/erasing is 10,000 times for full-flash(S3F8275X) and 100 times for half-flash  
(S3F8278X/F8274X).  
5. The chip erasing is available in Tool Program Mode only.  
17-13  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
MECHANICAL DATA  
18 MECHANICAL DATA  
OVERVIEW  
The S3C8275X/C8278X/C8274X microcontroller is currently available in a 64-pin QFP and LQFP package.  
23.90  
20.00  
±
±
0.30  
0.20  
0-8  
+ 0.10  
0.15 - 0.05  
0.10 MAX  
64-QFP-1420F  
#64  
+ 0.10  
- 0.05  
#1  
0.40  
0.05 MIN  
2.65  
3.00 MAX  
1.00  
0.15 MAX  
(1.00)  
±
0.10  
0.80 + 0.20  
NOTE: Dimensions are in millimeters.  
Figure 18-1. 64-Pin QFP Package Dimensions (64-QFP-1420F)  
18-1  
MECHANICAL DATA  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
12.00 BSC  
10.00 BSC  
0-7  
0.09~0.20  
0.08 MAX  
64-LQFP-1010  
#64  
+ 0.07  
0.20 - 0.03  
#1  
0.50 BSC  
0.10  
1.40  
±
±
0.05  
0.05  
1.60 MAX  
NOTE: Dimensions are in millimeters.  
Figure 18-2. 64-Pin LQFP Package Dimensions (64-LQFP-1010)  
18-2  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
S3F8275X/F8278X/F8274X FLASH MCU  
19 S3F8275X/F8278X/F8274X FLASH MCU  
OVERVIEW  
The S3F8275X/F8278X/F8274X single-chip CMOS microcontroller is the Flash MCU version of the  
S3C8275X/C8278X/C8274X microcontroller. It has an on-chip Flash ROM instead of masked ROM. The Flash  
ROM is accessed by serial data format.  
The S3F8275X/F8278X/F8274X is fully compatible with the S3C8275X/C8278X/C8274X, both in function and in  
pin configuration. Because of its simple programming requirements, the S3F8275X/F8278X/F8274X is ideal for  
use as an evaluation chip for the S3C8275X/C8278X/C8274X.  
NOTE: This chapter is about the Tool Program Mode of Flash MCU. If you want to know the User Program Mode, refer to the  
chapter 16. Embedded Flash Memory Interface.  
19-1  
S3F8275X/F8278X/F8274X FLASH MCU  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
SEG0/P5.7  
COM0/P6.0  
COM1/P6.1  
COM2/P6.2  
COM3/P6.3  
VLC0  
SDAT/VLC1  
SCLK/VLC2  
VDD/VDD  
1
2
3
4
5
6
7
8
51  
50  
49  
48  
47  
46  
45  
44  
43  
42  
41  
40  
39  
38  
37  
36  
35  
34  
33  
SEG14/P4.1  
SEG15/P4.0  
SEG16/P3.7  
SEG17/P3.6  
SEG18/P3.5  
SEG19/P3.4  
SEG20/P3.3  
SEG21/P3.2  
SEG22/P3.1  
SEG23/P3.0  
SEG24/P2.7  
SEG25/P2.6  
SEG26/P2.5  
SEG27/P2.4  
SEG28/P2.3  
SEG29/P2.2  
SEG30/P2.1  
SEG31/P2.0/VBLDREF  
P1.7/INT7  
S3F8275X  
S3F8278X  
S3F8274X  
9
VSS/VSS  
10  
11  
12  
13  
14  
15  
16  
17  
18  
19  
XOUT  
XIN  
VPP/TEST  
XTIN  
(64-QFP-1420F)  
XTOUT  
nRESET/nRESET  
VREG  
P0.0/INT0  
P0.1/INT1  
Figure 19-1. S3F8275X/F8278X/F8274X Pin Assignments (64-QFP-1420F)  
19-2  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
S3F8275X/F8278X/F8274X FLASH MCU  
SEG0/P5.7  
COM0/P6.0  
COM1/P6.1  
COM2/P6.2  
COM3/P6.3  
VLC0  
SDAT/VLC1  
SCLK/VLC2  
VDD/VDD  
1
2
3
4
5
6
7
8
48  
47  
46  
45  
44  
43  
42  
41  
40  
39  
38  
37  
36  
35  
34  
33  
SEG17/P3.6  
SEG18/P3.5  
SEG19/P3.4  
SEG20/P3.3  
SEG21/P3.2  
SEG22/P3.1  
SEG23/P3.0  
SEG24/P2.7  
SEG25/P2.6  
SEG26/P2.5  
SEG27/P2.4  
SEG28/P2.3  
SEG29/P2.2  
SEG30/P2.1  
SEG31/P2.0/VBLDREF  
P1.7/INT7  
S3F8275X  
S3F8278X  
S3F8274X  
9
VSS/VSS  
10  
11  
12  
13  
14  
15  
16  
XOUT  
XIN  
VPP/TEST  
XTIN  
(64-LQFP-1010)  
XTOUT  
nRESET/nRESET  
Figure 19-2. S3F8275X/F8278X/F8274X Pin Assignments (64-LQFP-1010)  
19-3  
S3F8275X/F8278X/F8274X FLASH MCU  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Table 19-1. Descriptions of Pins Used to Read/Write the Flash ROM  
During Programming  
Main Chip  
Pin Name  
VLC1  
Pin Name  
Pin No.  
I/O  
Function  
SDAT  
7
I/O  
Serial data pin. Output port when reading and  
input port when writing. Can be assigned as an  
Input or push-pull output port.  
VLC2  
TEST  
SCLK  
VPP  
8
I/O  
I
Serial clock pin. Input only pin.  
13  
S3F8278X/F8274X: Power supply pin for Flash  
ROM cell reading/writing. 12.5V is applied in  
Flash writing mode and 3.3V is applied in Flash  
reading mode.  
S3F8275X: Power supply pin for Flash ROM cell  
reading/writing. 3.3V is applied in Flash  
reading/writing mode because internal block  
makes 12.5V. So, TEST pin must be connected  
to VDD  
.
nRESET  
VDD/VSS  
nRESET  
VDD/VSS  
16  
I
I
Chip initialization  
9 / 10  
Power supply pin for logic circuit.  
VDD should be tied to +3.3 V during  
programming.  
Table 19-2. Comparison of S3F8275X/F8278X/F8274X and S3C8275X/C8278X/C8274X Features  
Characteristic  
Program memory  
Operating voltage (VDD  
S3F8275X/F8278X/F8274X  
16/8/4-Kbyte Flash ROM  
S3C8275X/C8278X/C8274X  
16/8/4-Kbyte mask ROM  
2.0 V to 3.6 V  
)
2.0 V to 3.6 V  
VDD = 3.3 V, VPP(TEST)=12.5V  
Flash ROM programming mode  
Pin configuration  
64-QFP, 64-LQFP  
64-QFP, 64-LQFP  
Flash ROM programmability  
User Program multi time  
Programmed at the factory  
NOTE: The V (Test) pin must be connected to V  
(S3F8275X only).  
PP  
DD  
19-4  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
OPERATING MODE CHARACTERISTICS  
S3F8275X/F8278X/F8274X FLASH MCU  
When 12.5 V is supplied to the VPP(TEST) pin of the S3F8275X/F8278X/F8274X, the Flash ROM programming  
mode is entered.  
The operating mode (read, write, or read protection) is selected according to the input signals to the pins listed in  
Table 19-3 below.  
Table 19-3. Operating Mode Selection Criteria  
VDD  
VPP (TEST)  
REG/MEM  
Address  
(A15-A0)  
R/W  
Mode  
3.3 V  
3.3 V  
12.5 V  
12.5 V  
0
0
1
0000H  
0000H  
0E3FH  
1
0
0
Flash ROM read  
Flash ROM program  
Flash ROM read protection  
NOTES:  
1. The V (Test) pin must be connected to V  
(S3F8275X only).  
PP  
DD  
2. "0" means Low level; "1" means High level.  
19-5  
S3F8275X/F8278X/F8274X FLASH MCU  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Table 19-4. D.C. Electrical Characteristics  
2.0 V to 3.6 V)  
Conditions  
8.0 MHz  
°
°
(TA  
=
25 C to + 85 C, VDD =  
Unit  
Parameter  
Symbol  
Min  
Typ  
Max  
(2)  
Supply current (1)  
IDD1  
Run mode:  
DD = 3.3 V ± 0.3 V  
3.0  
6.0  
mA  
V
Crystal oscillator  
C1 = C2 = 22pF  
4.0 MHz  
1.5  
3.0  
(2)  
Idle mode:  
8.0 MHz  
4.0 MHz  
0.5  
0.4  
1.6  
1.2  
IDD2  
VDD = 3.3 V ± 0.3 V  
Crystal oscillator  
C1 = C2 = 22pF  
(3)  
12.0  
2.0  
25.0  
4.0  
Run mode: VDD = 3.3 V ± 0.3 V,  
32 kHz crystal oscillator  
µA  
IDD3  
°
TA = 25 C, OSCCON.7=1  
(3)  
Idle mode: VDD = 3.3 V ± 0.3 V  
IDD4  
32 kHz crystal oscillator  
°
TA = 25 C, OSCCON.7=1  
(4)  
°
Stop mode;  
0.2  
2.0  
10  
IDD5  
TA = 25 C  
VDD = 3.3V ± 0.3 V  
°
°
TA = 25 C ~ +85 C  
NOTES:  
1. Supply current does not include current drawn through internal pull-up resistors, LCD voltage dividing resistors, the LVR  
block and external output current loads.  
2.  
3.  
4.  
I
I
I
and I  
include power consumption for sub clock oscillation.  
DD1  
DD3  
DD5  
DD2  
and I  
are current when main clock oscillation stops and the sub clock is used (OSCCON.7=1).  
DD4  
is current when main clock and sub clock oscillation stops.  
5. Every values in this table is measured when bits 4-3 of the system clock control register (CLKCON.4-.3) is set to 11B.  
19-6  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
S3F8275X/F8278X/F8274X FLASH MCU  
Instruction Clock  
fx (Main/Sub oscillation frequency)  
2 MHz  
8 MHz  
1.05 MHz  
4.2 MHz  
6.25 kHz (main)/8.2 kHz(sub)  
1
400 kHz(main)/32.8 kHz(sub)  
2
3
4
2.5  
3.6  
Supply Voltage (V)  
Instruction Clock = 1/4n x oscillator frequency (n = 1, 2, 8, 16)  
Figure 19-3. Operating Voltage Range  
19-7  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
DEVELOPMENT TOOLS  
20 DEVELOPMENT TOOLS  
OVERVIEW  
Samsung provides a powerful and easy-to-use development support system in turnkey form. The development  
support system is configured with a host system, debugging tools, and support software. For the host system, any  
standard computer that operates with MS-DOS, Windows 95, and 98 as its operating system can be used. One  
type of debugging tool including hardware and software is provided: the sophisticated and powerful in-circuit  
emulator, SMDS2+, and OPENice for S3C7, S3C9, S3C8 families of microcontrollers. The SMDS2+ is a new and  
improved version of SMDS2. Samsung also offers support software that includes debugger, assembler, and a  
program for setting options.  
SHINE  
Samsung Host Interface for In-Circuit Emulator, SHINE, is a multi-window based debugger for SMDS2+. SHINE  
provides pull-down and pop-up menus, mouse support, function/hot keys, and context-sensitive hyper-linked help.  
It has an advanced, multiple-windowed user interface that emphasizes ease of use. Each window can be sized,  
moved, scrolled, highlighted, added, or removed completely.  
SAMA ASSEMBLER  
The Samsung Arrangeable Microcontroller (SAM) Assembler, SAMA, is a universal assembler, and generates  
object code in standard hexadecimal format. Assembled program code includes the object code that is used for  
ROM data and required SMDS program control data. To assemble programs, SAMA requires a source file and an  
auxiliary definition (DEF) file with device specific information.  
SASM88  
The SASM88 is a relocatable assembler for Samsung's S3C8-series microcontrollers. The SASM88 takes a  
source file containing assembly language statements and translates into a corresponding source code, object  
code and comments. The SASM88 supports macros and conditional assembly. It runs on the MS-DOS operating  
system. It produces the relocatable object code only, so the user should link object file. Object files can be linked  
with other object files and loaded into memory.  
HEX2ROM  
HEX2ROM file generates ROM code from HEX file which has been produced by assembler. ROM code must be  
needed to fabricate a microcontroller which has a mask ROM. When generating the ROM code (.OBJ file) by  
HEX2ROM, the value "FF" is filled into the unused ROM area up to the maximum ROM size of the target device  
automatically.  
TARGET BOARDS  
Target boards are available for all S3C8-series microcontrollers. All required target system cables and adapters  
are included with the device-specific target board.  
20-1  
DEVELOPMENT TOOLS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
IBM-PC AT or Compatible  
RS-232C  
SMDS2+  
Target  
Application  
System  
PROM/OTP Writer Unit  
RAM Break/Display Unit  
Trace/Timer Unit  
Probe  
Adapter  
TB8275/8/4  
POD  
Target  
Board  
SAM8 Base Unit  
EVA  
Chip  
Power Supply Unit  
Figure 20-1. SMDS Product Configuration (SMDS2+)  
20-2  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
TB8275/8/4 TARGET BOARD  
DEVELOPMENT TOOLS  
The TB8275/8/4 target board is used for the S3C8275X/C8278X/C8274X microcontroller. It is supported with the  
SMDS2+.  
TB8275/8/4  
IDLE  
STOP  
To User_VCC  
OFF ON  
RESET  
7411  
Y1(sub-clock)  
25  
40  
1
41  
80  
J101  
J102  
160  
160 QFP  
S3E8270  
EVA Chip  
1
2
41  
42  
121  
81  
120  
Device Selection  
Select Smart Option Source  
Low: Internal  
1
Low: S3F8278/4  
High: S3F8275  
High: External  
39  
40  
79  
80  
Smart Option  
SMDS2  
SMDS2+  
Figure 20-2. TB8275/8/4 Target Board Configuration  
20-3  
DEVELOPMENT TOOLS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Table 20-1. Power Selection Settings for TB8275/8/4  
Operating Mode  
"To User_Vcc"  
Settings  
Comments  
The SMDS2/SMDS2+  
supplies VCC to the target  
TB8275  
TB8278  
TB8274  
To User_VCC  
Target  
System  
Off  
On  
V
SS  
board (evaluation chip) and  
the target system.  
V
CC  
V
CC  
SMDS2/SMDS2+  
The SMDS2/SMDS2+  
supplies VCC only to the target  
TB8275  
TB8278  
TB8274  
To User_VCC  
External  
Target  
System  
Off  
On  
V
CC  
board (evaluation chip).  
The target system must have  
its own power supply.  
V
SS  
V
CC  
SMDS2/SMDS2+  
NOTE: The following symbol in the "To User_Vcc" Setting column indicates the electrical short (off) configuration:  
Table 20-2. Main-clock Selection Settings for TB8275/8/4  
Main Clock Settings  
Operating Mode  
Comments  
Set the XI switch to “MDS”  
when the target board is  
connected to the  
X
IN  
EVA Chip  
S3E8270  
MDS  
XTAL  
SMDS2/SMDS2+.  
XOUT  
XIN  
No Connection  
100 Pin Connector  
SMDS2/SMDS2+  
Set the XI switch to “XTAL”  
when the target board is used  
as a standalone unit, and is  
not connected to the  
X
IN  
EVA Chip  
S3E8270  
MDS  
XTAL  
SMDS2/SMDS2+.  
XOUT  
XIN  
XTAL  
Target Board  
20-4  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
DEVELOPMENT TOOLS  
Comments  
Table 20-3. Select Smart Option Source Setting for TB8275/8/4  
Operating Mode  
"Smart Option Source"  
Settings  
The Smart Option is selected  
by external smart option  
switch (SW1)  
Select Smart  
Option Source  
Target  
System  
TB8275/8/4  
TB8275/8/4  
Internal  
External  
The Smart Option is selected  
by internal smart option area  
(003EH–003FH of ROM). But  
this selection is not available.  
Select Smart  
Option Source  
Target  
System  
Internal  
External  
Table 20-4. Smart Option Switch Settings for TB8275/8/4  
"Smart Option" Settings  
Comments  
The Smart Option is selected by this switch when the Smart Option  
source is selected by external. The B2–B0 are comparable to the  
003EH.2–.0. The B7–B5 are comparable to the 003EH.7–.5. The B8 is  
comparable to the 003FH.0. The B4–B3 is not connected.  
Smart Option  
Low : "0"  
High: "1"  
20-5  
DEVELOPMENT TOOLS  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
Table 20-5. Device Selection Settings for TB8275/8/4  
Operating Mode  
"Device Selection"  
Settings  
Comments  
Operate with TB8275  
Device Selection  
S3F8278/4  
S3F8275  
Target  
System  
TB8275  
Operate with TB8278/4  
Device Selection  
S3F8278/4 S3F8275  
Target  
System  
TB8278/4  
SMDS2+ SELECTION (SAM8)  
In order to write data into program memory that is available in SMDS2+, the target board should be selected to be  
for SMDS2+ through a switch as follows. Otherwise, the program memory writing function is not available.  
Table 20-6. The SMDS2+ Tool Selection Setting  
"JP2" Setting  
Operating Mode  
JP2  
R/W  
SMDS2+  
R/W  
SMDS2  
SMDS2+  
Target  
System  
IDLE LED  
The Yellow LED is ON when the evaluation chip (S3E8270) is in idle mode.  
STOP LED  
The Red LED is ON when the evaluation chip (S3E8270) is in stop mode.  
20-6  
S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X  
DEVELOPMENT TOOLS  
J101  
J102  
SEG0/P5.7  
COM1/P6.1  
COM3/P6.3  
VLC1  
1
3
5
7
2
4
6
P6.0/COM0  
P6.2/COM2  
VLC0  
VLC2  
VSS  
INT7/P1.7  
SEG30/P2.1  
SEG28/P2.3  
SEG26/P2.5  
SEG24/P2.7  
SEG22/P3.1  
SEG20/P3.3  
SEG18/P3.5  
SEG16/P3.7  
SEG14/P4.1  
SEG12/P4.3  
SEG10/P4.5  
SEG8/P4.7  
SEG6/P5.1  
SEG4/P5.3  
SEG2/P5.5  
N.C  
33  
35  
37  
39  
41  
43  
45  
47  
49  
51  
53  
55  
57  
59  
61  
63  
34  
36  
38  
40  
42  
44  
46  
48  
50  
52  
54  
56  
58  
60  
62  
64  
SEG31/P2.0/VBLDREF  
SEG29/P2.2  
SEG27/P2.4  
SEG25/P2.6  
SEG23/P3.0  
SEG21/P3.2  
SEG19/P3.4  
SEG17/P3.6  
SEG15/P4.0  
SEG13/P4.2  
SEG11/P4.4  
SEG9/P4.6  
SEG7/P5.0  
SEG5/P5.2  
SEG3/P5.4  
SEG1/P5.6  
N.C  
8
V
DD  
9
10  
12  
14  
16  
18  
20  
22  
24  
26  
28  
30  
32  
N.C  
TEST  
N.C  
11  
13  
15  
17  
19  
21  
23  
25  
27  
29  
31  
N.C  
N.C  
nRESET  
P0.0/INT0  
P0.2/INT2  
P0.4/TAOUT  
P0.6/CLKOUT  
P1.0/SCK  
P1.2/SI  
P1.4/INT4  
P1.6/INT6  
N.C  
V
REG  
INT1/P0.1  
T1CLK/P0.3  
TBOUT/P0.5  
BUZ/P0.7  
SO/P1.1  
INT3/P1.3  
INT5/P1.5  
N.C  
N.C  
N.C  
N.C  
N.C  
N.C  
N.C  
N.C  
N.C  
N.C  
N.C  
N.C  
N.C  
Figure 20-3. 40-Pin Connectors (J101, J102) for TB8275/8/4  
Target Board  
Target Board  
J101  
J102  
J102  
J101  
1
2 33 34  
33 34 1  
2
Target Cable for 40-pin Connector  
31 32 63 64  
63 64 31 32  
Figure 20-4. S3E8270 Cables for 64-QFP Package  
20-7  

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