MT9076BPR1 [ZARLINK]
Framer, PQCC68, LEAD FREE, PLASTIC, MS-018AE, LCC-68;
| 型号： | MT9076BPR1 |
| 厂家： | 
ZARLINK SEMICONDUCTOR INC |
| 描述： | Framer, PQCC68, LEAD FREE, PLASTIC, MS-018AE, LCC-68 PC 电信 电信集成电路 |
| 文件： | 总172页 (文件大小：959K) |
| 中文： | 中文翻译 | 下载： | 下载PDF数据表文档文件 |
MT9076B
T1/E1/J1 3.3 V Single Chip Transceiver
Data Sheet
September 2011
Features
•
•
•
Combined T1/E1/J1 framer and LIU, with PLL and
3 HDLCs
Ordering Information
MT9076BPR1 68 Pin PLCC* Tape & Reel
In T1/J1 mode the LIU can recover signals
attenuated by up to 36 dB (at 772 kHz)
MT9076BB1
MT9076BP1
80 Pin LQFP* Trays
68 Pin PLCC* Tubes
*Pb Free Matte Tin
In E1 mode the LIU can recover signals
attenuated by up to 40 dB (at 1.024 MHz)
-40C to +85C
•
•
•
Low jitter digital PLL (intrinsic jitter < 0.02UI)
HDLCs can be assigned to any timeslot
Comprehensive alarm detection, performance
monitoring and error insertion functions
Applications
•
•
•
•
•
2.048 Mbit/s or 8.192 Mbit/s ST-BUS streams
Support for Inverse Mux for ATM (IMA)
Support for V5.1 and V5.2 Access Networks
3.3 V operation with 5 V tolerant inputs
•
•
•
•
•
•
T1/E1/J1 add/drop multiplexers
Access networks
Wireless base stations
CO and CPE equipment interfaces
Primary rate ISDN nodes
Digital Cross-connect Systems (DCS)
Intel or Motorola non-multiplexed 8-bit
microprocessor port
•
JTAG boundary scan
TxDL TxDLCLK
TxMF
TxAO TxB TxA
DSTi
CSTi
ST-BUS
Interface
Transmit Framing, Error,
Test Signal Generation and Slip Buffer
Line
Driver
TTIP
TRING
Tdi
Tdo
PL Loop
Tms
Tclk
Trst
ST Loop
National
Bit Buffer
S/FR
Jitter Attenuator
& Clock Control
IRQ
BS/LS
OSC1
OSC2
D7~D0
Data Link,
CAS
AC4
HDLC0
HDLC1
Buffer
AC0
DG Loop
R/W/WR
CS
RTIP
RRING
DS/RD
DSTo
CSTo
Receive Framing, Performance Monitoring,
Alarm Detection, 2 Frame Slip Buffer
ST-BUS
Interface
RxDLCLK RxDL
RxMF/TxFP
LOS
RxFP
Exclk F0b C4b
Figure 1 - MT9076 Functional Block
1
Zarlink Semiconductor Inc.
Zarlink, ZL and the Zarlink Semiconductor logo are trademarks of Zarlink Semiconductor Inc.
Copyright 2002-2011, Zarlink Semiconductor Inc. All Rights Reserved.
MT9076B
Data Sheet
Description
The MT9076 is a highly featured single chip solution for terminating T1/E1/J1 trunks. It contains a long-haul LIU, an
advanced framer, a high performance PLL and 3 HDLCs.
In T1 mode, the MT9076 supports D4, ESF and SLC-96 formats meeting the latest recommendations including
AT&T PUB43801, TR-62411; ANSI T1.102, T1.403 and T1.408; Telcordia GR-303-CORE.
In E1 mode, the MT9076 supports the latest ITU-T Recommendations including G.703, G.704, G.706, G.732, G.775,
G.796, G.823, G.964 (V5.1), G.965 (V5.2) and I.431. It also supports ETSI ETS 300 011, ETS 300 166, ETS 300
233, ETS 300 324 (V5.1) and ETS 300 347 (V5.2).
Change Summary
Changes from the June 2006 issue to the September 2011 issue.
Page
Item
Change
1
Ordering Information
Removed leaded packages as per PCN notice.
2
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
8
6
4
2
68 66 64 62
CS
RESET
IRQ
10
12
14
16
18
20
22
24
26
60
58
56
54
52
50
48
46
44
TxAO
Trst
Tclk
Tms
Tdo
D0
D1
D2
D3
Tdi
GNDATX
TRING
TTIP
VDDATX
VDD2
VSS2
IC1
RxFP
F0b
C4b
VSS5
IC4
INT/MOT
VDD5
D4
68 PIN PLCC
D5
D6
D7
R/W/WR
AC0
Exclk
28 30 32 34 36 38 40 42
60 58 56 54 52
62
50
48
46
44 42
40
NC
NC
TxAO
Trst
Tclk
NC
NC
CS
38
36
64
RESET
IRQ
66
68
70
72
74
76
78
80
Tms
Tdo
Tdi
D0
D1
D2
D3
34
32
GNDATX
TRING
TTIP
VDDATX
VDD2
VSS2
IC1
RxFP
F0b
C4b
80 PIN LQFP
VSS5
IC4
INT/MOT
VDD5
D4
30
28
26
24
22
D5
D6
D7
R/W/WR
AC0
NC
Exclk
NC
2
4
6
8
10 12 14
16 18
20
Figure 2 - Pin Connections
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Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Pin Description
Pin #
Name
Description
PLCC LQFP
1
51
OSC1 Oscillator (3 V Input). This pin is either connected via a 20.000 MHz crystal to OSC2
where a crystal is used, or is directly driven when a 20.000 MHz. oscillator is employed.
2
52
OSC2 Oscillator (3 V Output). Connect a 20.0 MHz crystal between OSC1 and OSC2. Not
suitable for driving other devices.
3
4
5
53
54
55
VSS4
VDD4
CSTo
Negative Power Supply. Digital ground.
Positive Power Supply. Digital supply (+3.3 V 5%).
Control ST-BUS (5 V tolerant Output). CSTo carries serial streams for CAS and CCS
respectively a 2.048 Mbit/s ST-BUS status stream which contains the 30 receive
signaling nibbles (ABCDZZZZ or ZZZZABCD). The most significant nibbles of each ST-
BUS time slot are valid and the least significant nibbles of each ST-BUS time slot are
tristated when control bit MSN (page 01H, address 1AH, bit 1) is set to 1. If MSN=0, the
position of the valid and tristated nibbles are reversed.
6
56
CSTi
Control ST-BUS (5 V tolerant Input). CSTi carries serial streams for CAS and CCS
respectively a 2.048 Mbit/s ST-BUS control stream which contains the 30 transmit
signaling nibbles (ABCDXXXX or XXXXABCD) when RPSIG=0. When RPSIG=1 this
pin has no function. The most significant nibbles of each ST-BUS time slot are valid and
the least significant nibbles of each ST-BUS time slot are ignored when control bit MSN
(page 01H, address 1AH, bit 1) is set to 1. If MSN=0, the position of the valid and
ignored nibbles is reversed.
7
8
57
58
DSTo
DSTi
Data ST-BUS (5 V tolerant Output). A 2.048 Mbit/s serial stream which contains the
24/30 PCM(T1/E1) or data channels received on the PCM 24/30 (T1/E1) line.
Data ST-BUS (5 V tolerant Input). A 2.048 Mbit/s serial stream which contains the
24/30 (T1/E1) PCM or data channels to be transmitted on the PCM 24/30 (T1/E1)
line.
9
59
DS/RD Data/Read Strobe (5 V tolerant Input).
In Motorola mode (DS), this input is the active low data strobe of the processor
interface. In Intel mode (RD), this input is the active low read strobe of the processor
interface.
10
11
63
64
CS
Chip Select (5 V tolerant Input). This active low input enables the non-multiplexed
parallel microprocessor interface of the MT9076. When CS is set to high, the
microprocessor interface is idle and all bus I/O pins will be in a high impedance state.
RESET RESET (5 V tolerant Input). This active low input puts the MT9076 in a reset condition.
RESET should be set to high for normal operation. The MT9076 should be reset after
power-up. The RESET pin must be held low for a minimum of 1 sec. to reset the
device properly.
12
65
IRQ
Interrupt Request (5 V tolerant Output). A low on this output pin indicates that an
interrupt request is presented. IRQ is an open drain output that should be connected to
V
DD through a pull-up resistor. An active low CS signal is not required for this pin to
function.
13 - 66-69 D0 - D3 Data 0 to Data 3 (5 V tolerant Three-state I/O). These signals combined with D4-D7
16
form the bidirectional data bus of the parallel processor interface (D0 is the least
significant bit).
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Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Pin Description (continued)
Pin #
Name
Description
PLCC LQFP
17
18
19
70
71
72
VSS5 Negative Power Supply. Digital ground.
IC4 Internal Connection (3 V Input). Tie to VSS (Ground) for normal operation.
INT/MOT Intel/Motorola Mode Selection (5 V tolerant Input). A high on this pin configures the
processor interface for the Intel parallel non-multiplexed bus type. A low configures the
processor interface for the Motorola parallel non-multiplexed type.
20
73
VDD5 Positive Power Supply. Digital supply (+3.3 V 5%).
21 - 74-77 D4 - D7 Data 4 to Data 7 (5 V tolerant Three-state I/O). These signals combined with D0-D3
24
25
form the bidirectional data bus of the parallel processor interface (D7 is the most
significant bit).
78
R/W/WR Read/Write/Write Strobe (5 V tolerant Input). In Motorola mode (R/W), this input
controls the direction of the data bus D[0:7] during a microprocessor access. When R/W
is high, the parallel processor is reading data from the MT9076. When low, the parallel
processor is writing data to the MT9076. For Intel mode (WR), this active low write
strobe configures the data bus lines as output.
26 -
30
79, AC0 - AC4 Address/Control 0 to 4 (5 V tolerant Inputs). Address and control inputs for the
2-5
non-multiplexed parallel processor interface. AC0 is the least significant input.
31
6
GNDARx Receive Analog Ground. Analog ground for the LIU receiver.
32
33
7
8
RTIP
Receive TIP and RING (3 V Input). Differential inputs for the receive line signal - must
RRING be transformer coupled (See Figure 5 on page 24). In digital framer mode these pins
accept digital 3 volt signals from a physical layer device. They may accept a split phase
unipolar signal (RTIP and RRING employed) or an NRZ signal (RTIP only used).
34
35
36
37
9
VDDARx Receive Analog Power Supply. Analog supply for the LIU receiver (+3.3 V 5%).
VDD1 Positive Power Supply. Digital supply (+3.3 V 5%).
VSS1 Negative Power Supply. Digital ground.
10
11
12
TxA
Transmit A (5 V tolerant Output). When the internal LIU is disabled (digital framer
only mode), if control bit NRZ=1, an NRZ output data is clocked out on pin TxA with the
rising edge of Exclk (TxB has no function when NRZ format is selected). If NRZ=0, pins
TxA and TxB are a complementary pair of signals that output digital dual-rail data
clocked out with the rising edge of Exclk.
38
39
13
TxB
Transmit B (5 V tolerant Output). When the internal LIU is disabled and control bit
NRZ=0, pins TxA and TxB are a complementary pair of signals that output digital dual-
rail data clocked out with the rising edge of Exclk.
14 RxDLCLK Data Link Clock (5 V tolerant Output). A gapped clock signal derived from the
extracted line clock, available for an external device to clock in RxDL data (at 4, 8, 12,
16 or 20 kHz) on the rising edge.
40
41
15
RxDL
Receive Data Link (5 V tolerant Output). A serial bit stream containing received line
data after zero code suppression. This data is clocked out with the rising edge of Exclk.
16
TxMF Transmit Multiframe Boundary (5 V tolerant Input). An active low input used to set
the transmit multiframe boundary (CAS or CRC multiframe). The MT9076 will generate
its own multiframe if this pin is held high. This input is usually pulled high for most
applications.
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Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Pin Description (continued)
Pin #
Name
Description
PLCC LQFP
42
17 RxMF/TxF Receive Multiframe Boundary / Transmit Frame Boundary (5 V tolerant Output). If
P
the control bit Tx8KEN (page 02H address 10H bit 2) is low, this negative output pulse
delimits the received multiframe boundary. The next frame output on the data stream
(DSTo) is basic frame zero on the T1 or PCM 30 link. In E1 mode this receive
multiframe signal can be related to either the receive CRC multiframe (page 01H,
address 17H, bit 6, MFSEL=1) or the receive signaling multiframe (MFSEL=0). If the
control bit Tx8KEN is set high, this positive output pulse delimits the frame boundary
(the first bit transmit in the frame) for the digital output stream on pins TXA and TXB.
43
44
18
22
BS/LS Bus/Line Synchronization Mode Selection (5 V tolerant Input). If high, C4b and F0b
will be inputs; if low, C4b and F0b will be outputs.
Exclk
C4b
2.048 MHz in E1 mode or 1.544 MHz in T1 mode, Extracted Clock (5 V tolerant
Output). The clock extracted from the received signal and used internally to clock in
data received on RTIP and RRING.
45
46
47
23
24
25
4.096 MHz System Clock (5 V tolerant Input/Output). C4b is the clock for the ST-
BUS sections and transmit serial PCM data of the MT9076. In the free-run
(S/FR/Exclki=0) or line synchronous mode (S/FR/Exclki=1 and BS/LS=0) this signal is
an output, while in bus synchronous mode (S/FR/Exclki=1 and BS/LS=1) this signal is
an input clock.
F0b
Frame Pulse (5 V tolerant Input/Output). This is the ST-BUS frame synchronization
signal, which delimits the 32 channel frame of CSTi, CSTo, DSTi, DSTo and the
PCM30 link. In the free-run (S/FR/Exclki=0) or line synchronous mode (S/FR/Exclki=1
and BS/LS=0) this signal is an output, while in bus synchronous mode (S/FR/Exclki=1
and BS/LS=1) this signal is an input.
RxFP
Receive Frame Pulse/Receive CCS Clock (5 V tolerant Output). An 8kHz pulse
signal, which is low for one extracted clock period. This signal is synchronized to the
receive DS1 or PCM 30 basic frame boundary.
48
49
50
51
26
27
28
29
IC1
Internal Connection. Must be left open for normal operation.
Negative Power Supply. Digital ground.
VSS2
VDD2
Positive Power Supply. Digital supply (+3.3 V 5%).
VDDATx Transmit Analog Power Supply. Analog supply for the LIU transmitter (+3.3 V 5%).
52
53
30
31
TTIP Transmit TIP and RING(Output). Differential outputs for the transmit line signal - must
TRING be transformer coupled (See Figure 5 on page 24).
54
55
56
32
33
34
GNDATx Transmit Analog Ground. Analog ground for the LIU transmitter.
Tdi
IEEE 1149.1a Test Data Input (3 V Input). If not used, this pin should be pulled high.
Tdo
IEEE 1149.1a Test Data Output (5 V tolerant Output). If not used, this pin should be
left unconnected.
57
35
Tms
IEEE 1149.1a Test Mode Selection (3 V Input). If not used, this pin should be pulled
high.
58
59
36
37
Tclk
Trst
IEEE 1149.1a Test Clock Signal (3 V Input). If not used, this pin should be pulled high.
IEEE 1149.1a Reset Signal (3 V Input). If not used, this pin should be held low.
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Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Pin Description (continued)
Pin #
Name
Description
PLCC LQFP
60
38
TxAO Transmit All Ones (Input). High - TTIP, TRING will transmit data normally. Low - TTIP,
TRING will transmit an all ones signal.
61
43
LOS
Loss of Signal or Synchronization (5 V tolerant Output). When high, and LOS/LOF
(page 0, this signal indicates that the receive portion of the MT9076 is either not
detecting an incoming signal (bit LLOS on page 03H address 16H is one) or is detecting
a loss of basic frame alignment condition (bit TSYNC (T1), SYNC (E1) on page 03H
address 10H is one). If LOS/LOF=1, a high on this pin indicates a loss of signal
condition.
62
63
64
44
45
IC2
IC3
Internal Connection (3 V Input). Tie to VSS (Ground) for normal operation.
Internal Connection (3 V Input). Tie to VSS (Ground) for normal operation.
46 TxDLCLK Transmit Data Link Clock (5 V tolerant Output). A gapped clock signal derived from a
gated 2.048 Mbit/s clock for transmit data link at 4, 8, 12, 16 or 20 kHz. The transmit
data link data (TxDL) is clocked in on the rising edge of TxDLCLK. TxDLCLK can also
be used to clock DL data out of an external serial controller.
65
66
47
TxDL
Transmit Data Link (5 V tolerant Input). An input serial stream of transmit data link
data at 4, 8, 12, 16 or 20 kbit/s.
48 S/FR/Excl Synchronization/ Freerun / Extracted Clock (5 V tolerant Input). If low, and the
ki
internal LIU is enabled, the MT9076 is in free run mode. Pins 45 C4b and 46 F0b are
outputs generating system clocks. Slips will occur in the receive slip buffer as a result of
any deviation between the MT9076's internal PLL (which is free - running) and the
frequency of the incoming line data. If high, and the internal LIU is enabled, the MT9076
is in Bus or Line Synchronization mode depending on the BS/LS pin. If the internal LIU
is disabled, in digital framer mode, this pin (Exclki) takes an input clock 1.544 MHz (T1)/
2.048 MHz (E1) that clocks in the received digital data on pins RXA and RXB with its
rising edge.
67
68
49
50
VDD3 Positive Power Supply. Digital supply (+3.3 V 5%).
VSS3 Negative Power Supply. Digital ground.
Device Overview
The MT9076 is a T1/E1/J1 single chip transceiver that incorporates an advanced framer, a long-haul LIU (Line
Interface Unit), a low jitter PLL (Phase Locked Loop) and 3 HDLCs (High-level Data Link Controller). The T1, E1
and J1 operating modes are selectable under software control.
Standards Compliance
In T1 mode, the MT9076 meets or supports the latest recommendations including Telcordia GR-303-CORE, AT&T
PUB43801, TR-62411, ANSI T1.102, T1.403 and T1.408. In T1 ESF mode the CRC-6 calculation and yellow alarm
can be configured to meet the requirements of a J1 interface.
In E1 mode, the MT9076 meets or supports the latest ITU-T Recommendations for PCM 30 and ISDN primary rate
including G.703, G.704, G.706, G.732, G.775, G.796, G.823, G.964 (V5.1), G.965 (V5,2) and I.431. It also meets or
supports ETSI ETS 300 011, ETS 300 166, ETS 300 233, ETS 300 324 (V5.1) and ETS 300 347 (V5.2).
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Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Microprocessor Port
The MT9076 registers are accessible via an 8-bit parallel Motorola or Intel non-multiplexed microprocessor
interface.
LIU
The MT9076 LIU interfaces the digital framer functions to either the DS1 (T1 mode) or PCM 30 (E1 mode)
transformer-isolated four wire line.
In T1 mode, the LIU can pre-equalize the transmit signal to meet the T1.403 and T1.102 pulse templates after
attenuation by 0 - 655 feet of 22 AWG PIC cable, alternatively it can provide line build outs of 7.5 dB, 15 dB and
22.5 dB. In T1 mode the receiver can recover signals attenuated by up to 36 dB at 772 kHz.
In E1 mode, the LIU transmits signals that meet the G.703 2.048 Mbit/s pulse template and the receiver can recover
signals attenuated by up to 40 dB at 1024 kHz.
Digital Framer Only Mode
To accommodate some special applications, the MT9076 supports a digital framer only mode that provides direct
access to the transmit and receive data in digital format, i.e., by-passing the analog LIU front-end. In digital framer
only mode, the MT9076 supports unipolar non-return to zero or bipolar return to zero data.
PLL and Slip Buffers
The MT9076 PLL attenuates jitter from 2.5 Hz with a roll-off of 20 dB/decade. The intrinsic jitter is less than 0.02 UI.
The device can operate in one of three timing modes: System Bus Synchronous Mode, Line Synchronous Mode, or
Free-run Mode. In all three timing modes the low jitter output of the PLL provides timing to the transmit side of the
LIU.
In T1 mode, the receive and transmit paths both include two-frame slip buffers. The transmit slip buffer features
programmable delay and serves as a Jitter Attenuator (JA) FIFO and a rate converter between the ST-BUS and the
1.544 Mbit/s T1 line rate.
In E1 mode, the receive path includes a two-frame slip buffer and the transmit path contains a 128 bit Jitter
Attenuator (JA) FIFO with programmable depth.
Interface to the System Backplane
On the system side the MT9076 framers can interface to a 2.048 Mbit/s or 8.192 Mbit/s ST-BUS backplane.
There is an asynchronous mode for Inverse MUX for ATM (IMA) applications, this enables the framer to interface to
a 1.544 Mbit/s (T1) or 2.048 Mbit/s (E1) serial bus with asynchronous transmit and receive timing.
Framing Modes
The MT9076 framers operate in termination mode or transparent mode. In the receive transparent mode, the
received line data is channelled to the DSTo pin with arbitrary frame alignment. In the transmit transparent mode,
no framing or signaling is imposed on the data transmitted from the DSTi pin onto the line.
In T1 mode, the framers operate in any of the following framing modes: D4, Extended Superframe (ESF) or SLC-
96.
In E1 mode, the framers run three framing algorithms: basic frame alignment, signaling multiframe alignment and
CRC-4 multiframe alignment. The Remote Alarm Indication (RAI) bit is automatically controlled by an internal state
machine.
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Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Access to the Maintenance Channel
The T1 ESF Facility Data Link (FDL) bits can be accessed in the following three ways: Through the data link pins
TxDL, RxDL, RxDLC and TxDLC; through internal registers for Bit Oriented Messages; through an embedded
HDLC.
In E1 mode, the Sa bits (bits 4-8 of the non-frame alignment signal) can be accessed in four ways: Through data
link pins TxDL, RxDL, RxDLC and TxDLC, through single byte transmit and receive registers; through five byte
transmit and receive national bit buffers; through an embedded HDLC.
Robbed Bit Signaling/Channel Associated Signaling
Robbed bit signaling and channel associated signaling information can be accessed two ways: Via the microport;
via the CSTi and CSTo pins. Signaling information is frozen upon loss of multiframe alignment.
In T1 mode, the MT9076 supports AB and ABCD robbed bit signaling. Robbed bit signaling can be enabled on a
channel by channel basis.
In E1 mode the MT9076 supports Channel Associated Signaling (CAS) multiframing.
HDLCs
The MT9076 provides three embedded HDLCs with 128 byte deep transmit and receive FIFOs.
In T1 mode, the embedded HDLCs can be assigned to any channel and can operate at 56 kbit/s or 64 kbit/s. In T1
ESF mode, HDLCO can be assigned to the 4 kbit/s FDL.
In E1 mode, the embedded HDLCs can be assigned to any timeslot and can operate at 64 kbit/s. HDLCO can be
assigned to timeslot 0 Sa bits (bits 4-8 of the non-frame alignment signal) and can operate at 4,8,12,16 or 20 kbit/s.
Performance Monitoring and Debugging
The MT9076 has a comprehensive suite of performance monitoring and debugging features. These include error
counters, loopbacks, deliberate error insertion and a 215 –1 QRS/PRBS generator/detector.
Interrupts
The MT9076 provides a comprehensive set of maskable interrupts. Interrupt sources consist of synchronization
status, alarm status, counter indication and overflow, timer status, slip indication, maintenance functions and
receive signaling bit changes.
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Zarlink Semiconductor Inc.
MT9076B
Data Sheet
MT9076 Detailed Feature List
Standards Compliance and Support
T1/J1 Mode
E1 Mode
ANSI:
ETSI:
T1.102,T1.231, T1.403, T1.408
ETS 300 011, ETS 300 166, ETS 300 233,
ETS 300 324, ETS 300 347
AT&T:
TR 62411, PUB43801
ITU:
G.703, G.704, G.706, G.732 G.775,
G.796, G.823, I.431, G.964, G.965
Telcordia:
GR-303-CORE
TTC:
JT-G703, JT-G704, JT-G706
Line Interface Unit (LIU)
•
•
•
•
•
•
•
•
T1 and E1 modes use the same 1:1 transmit and receive transformers
Internal register allows termination impedance to be changed under software control.
Programmable pulse shapes and pulse amplitudes
Automatic or manual receiver equalization
Receive signal peak amplitude is reported with 8-bit resolution
Output pin to indicate Loss Of Signal/ Loss Of Frame synchronization
LIU output is disabled at power-up until enabled by software
Input pin to force transmission of AIS
T1/J1 Mode
E1 Mode
•
•
•
Reliably recovers signals with cable
attenuation up to 36 dB @ 772 kHz
•
•
•
Reliably recovers signals with cable
attenuation up to 40 dB @ 1024 kHz
Transmit pulse meets T1.403 and T1.102
pulse templates
Transmit pulse meets G.703 pulse template
Indicates analog Los Of Signal if the
received signal is more than 20 dB or 40 dB
below nominal for more than 1 ms
Indicates analog Los Of Signal if the received
signal is more than 20 dB or 40 dB below
nominal for more than 1 ms
•
Receiver tolerates jitter as required by AT&T
TR62411
•
Receiver tolerates jitter as required by ETSI
ETS 300 011
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Zarlink Semiconductor Inc.
MT9076B
Data Sheet
T1/J1 Mode
E1 Mode
•
Transmit Pre-equalization and Line Build Out
options:
0-133 feet
133-266 feet
266-399 feet
399-533 feet
533-655 feet
-7.5 dB
-15 dB
-22.5 dB
Digital Framer Mode
•
•
•
The LIU can be disabled and bypassed to allow the MT9076 to be used as a digital framer
Single phase NRZ or two phase NRZ modes are software selectable
Line coding is software selectable
Phase Lock Loop
•
•
•
•
•
•
•
•
Locks to a 4.096 MHz input clock, or to the 1.544 MHz / 2.048 MHz extracted clock
IMA mode locks to 1,544 MHz or 2,048 MHz external clock
Attenuates jitter from less than 2.5 Hz with a roll off of 20 dB/decade
Attenuates jitter in the transmit or receive direction
Intrinsic jitter less than 0.02 UI
Meets the jitter characteristics as specified in AT&T TR62411
Meets the jitter characteristics as specified in ETS 300 011
Can be operated in Free-run, Line Synchronous or System Bus Synchronous modes
Access and Control
•
•
MT9076 registers can be accessed via an 8-bit non-multiplexed parallel microprocessor port
The parallel port can be configured for Motorola or Intel style control signals
Backplane Interfaces
•
•
2.048 Mbit/s or 8.192 Mbit/s ST-BUS
IMA mode, 1.544 Mbit/s (T1) or 2.048 Mbit/s (E1) serial bus with asynchronous transmit and receive timing
for Inverse MUX for ATM (IMA) applications. Slip buffers are bypassed and signaling is disabled.
•
•
•
CSTo/CSTi pins can be used to access the receive/transmit signaling data
RxDL pin can be used to access the entire B8ZS/HDB3 decoded receive stream including framing bits
TxDL pin can be used to transmit data on the FDL (T1) or the Sa bits (E1)
T1/J1 Mode
E1 Mode
•
•
PCM-24 channels 1-24 are mapped to ST-
BUS channels 0-23 respectively
•
PCM-30 timeslots 0-31 are mapped to ST-
BUS channels 0-31 respectively
The framing-bit is mapped to ST-BUS
channel 31
11
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Data Link
T1/J1 Mode
E1 Mode
•
Three methods are provided to access the
datalink:
•
Two methods are provided to access the
datalink:
1. TxDL and RxDL pins support transmit and
receive datalinks
1. TxDL and RxDL pins support transmit and
receive datalinks over the Sa4~Sa8 bits
2. Bit Oriented Messages are supported via
internal registers
2. An internal HDLC can be assigned to
transmit/receive data via the Sa4~Sa8 bits
3. An internal HDLC can be assigned to
transmit/receive over the FDL in ESF mode
•
In transparent mode, if the Sa4 bit is used for
an intermediate datalink, the CRC-4
remainder can be updated to reflect changes
to the Sa4 bit
Access and Monitoring for National (Sa) Bits (E1 mode only)
In addition to the datalink functions, the Sa bits can be accessed using:
•
•
•
•
Single byte register
Five byte transmit and receive national bit buffers
A maskable interrupt is generated on the change of state of any Sa bit
Three Embedded Floating HDLCs (HDLC0, HDLC1, HDLC2)
•
•
•
•
•
•
Successive writes/reads can be made to the transmit/receive FIFOs at 160 ns or 80 ns intervals
Flag generation and Frame Check Sequence (FCS) generation and detection, zero insertion and deletion
Continuous flags, or continuous 1s are transmitted between frames
Transmit frame-abort
Transmit end-of-packet after a programmable number of bytes (up to 65,536 bytes)
Invalid frame handling:
•
•
•
•
•
Frames yielding an incorrect FCS are tagged as bad packets
Frames with fewer than 25 bits are ignored
Frames with fewer than 32 bits between flags are tagged as bad packets
Frames interrupted by a Frame-Abort sequence remain in the FIFO and an interrupt is generated
Access is provided to the receive FCS
•
•
•
•
•
•
•
•
•
FCS generation can be inhibited for terminal adaptation
Recognizes single byte, dual byte and all call addresses
Independent, 16-128 byte deep transmit and receive FIFOs
Receive FIFO maskable interrupts for near full (programmable levels) and overflow conditions
Transmit FIFO maskable interrupts for nearly empty (programmable levels) and underflow conditions
Maskable interrupts for transmit end-of-packet and receive end-of-packet
Maskable interrupts for receive bad-frame (includes frame abort)
Transmit-to-receive and receive-to-transmit loopbacks are provided
Transmit and receive bit rates and enables are independent
12
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
•
Frame aborts can be sent under software control and they are automatically transmitted in the event of a
transmit FIFO underrun
T1/J1 Mode
E1 Mode
HDLC0
HDLC0
•
Assignable to the ESF Facility Data Link or
any channel
•
Assigned to timeslot-0, bits Sa4~Sa8 or any
other timeslot
•
Operates at 4 kbps, 56 kbps or 64 kbps
•
Operates at 4, 8, 12, 16 or 20 kbps
depending on which Sa bits are selected for
HDLC0 use
HDLC1, HDLC2
•
•
Assignable to any channel
HDLC1, HDLC2
Operates at 56 kbps or 64 kbps
•
•
Assigned to any timeslot except timeslot-0
Operates at 64 kbps
Slip Buffers
T1/J1 Mode
Transmit Slip Buffer
E1 Mode
Receive Slip Buffer
•
Two-frame slip buffer capable of performing a
controlled slip
•
•
•
Two-frame slip buffer capable of performing a
controlled slip
•
Intended for rate conversion and jitter
attenuation in the transmit direction
Wander tolerance of 208 UI peak-to-peak
•
•
Programmable delay
Indication of slip direction
Transmit slips are independent of receive
slips
•
Indication of slip direction
Receive Slip Buffer
•
Two-frame slip buffer capable of performing a
controlled slip
•
•
Wander tolerance of 142 UI (92 s) peak
Indication of slip direction
Jitter Attenuator FIFO
•
A jitter attenuator FIFO is available on the transmit side in E1 mode and in IMA mode. The depth of the JA
FIFO can be configured to be from16 bits deep to 128 bits deep in 16 bit increments
Inverse Mux for ATM (IMA) Mode
T1/J1 Mode
E1 Mode
•
•
Transmit and receive datastreams are
independently timed
•
Transmit and receive datastreams are
independently timed
The transmit clock synchronizes to a
1.544 MHz clock
•
•
Receive slip buffer is bypassed
CAS and HDLCs are disabled
13
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
T1/J1 Mode
E1 Mode
•
•
Transmit and receive slip buffers are
bypassed
Robbed bit signaling and HDLCs are disabled
Framing Algorithm
T1/J1 Mode
Synchronizes with D4 or ESF protocols
E1 Mode
•
•
•
•
•
•
MT9076 contains 3 distinct and independent
framing algorithms
Supports SLC-96 framing
1. Basic frame alignment
Framing circuit is off-line
2. Signaling multiframe alignment
3. CRC-4 multiframe alignment
Transparent transmit and receive modes
Transparent transmit and receive modes
In D4 mode the Fs bits can optionally be
cross checked with the Ft bits
•
•
Automatic interworking between interfaces
with and without CRC-4 processing
capabilities is supported
•
The start of the ESF multiframe can be
determined by the following methods:
•
•
•
Free-run
•
An automatic reframe is forced if 3
consecutive frame alignment patterns or
three consecutive non-frame alignment bits
are received in error
Software reset
Synchronized to the incoming multiframe
•
•
An automatic reframe is initiated if the
framing bit error density exceeds the
programmed threshold
•
In transparent mode, no reframing is forced
by the device
In transparent mode, no reframing is forced
by the device
•
•
Software can force a reframe at any time
Software can force a multiframe reframe at
any time
•
•
Software can force a reframe at any time
In ESF mode the CRC-6 bits can be
optionally confirmed before forcing a new
frame alignment
•
E-bits can optionally be set to zero until CRC
synchronization is achieved
•
•
•
Optional automatic RAI
•
During a reframe the signaling bits are frozen
and error counting for Ft, Fs, ESF framing
pattern and CRC-6 bits is suspended
Supports CAS multiframing
Optional automatic Y-bit to indicate CAS
multiframe alignment
•
•
•
If J1 CRC-6 is selected the Fs bits are
included in the CRC-6 calculation
J1 CRC-6 and J1 Yellow Alarm can be
independently selected
Supports robbed bit signaling
Line Coding
T1/J1 Mode
E1 Mode
•
•
•
B8ZS or AMI line coding
Pulse density enforcement
Forced ones insertion
•
HDB3 or AMI line coding
14
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Channel Associated Signaling
•
•
•
•
•
•
•
ABCD or AB bits can be automatically inserted and extracted
Transmit ABCD or AB bits can be passed via the microport or via the CSTi pin
Receive ABCD or AB bits are accessible via the microport or via the CSTo pin
Most significant or least significant CSTi/CSTo nibbles can be selected to carry signaling bits
Unused nibble positions in the CSTi/CSTo bandwidth are tri-stated
An interrupt is provided in the event of changes in any of the signaling bits
Receive signaling bits are frozen if signaling multiframe alignment is lost
T1/J1 Mode
E1 Mode
•
Signaling bits can be debounced by 6 ms
•
Signaling bits can be debounced by 14 ms
Alarms
T1/J1 Mode
E1 Mode
D4 Yellow Alarm, two types
Remote Alarm Indication (RAI)
• Bit 3 of the receive NFAS
1. Bit position 2 is zero for virtually every DS0
over 48ms
2. Two consecutive ones in the S-bit position
of the twelfth frame
Alarm Indication Signal (AIS)
•
Unframed all ones signal for at least a double
frame or two double frames
ESF Yellow Alarm, two types
1. Reception of 0000000011111111 in seven or
more codewords out of ten (T1)
Timeslot 16 Alarm Indication Signal
All ones signal in timeslot 16
2. Reception of 1111111111111111 in seven or
more codewords out of ten (J1)
•
Loss Of Signal (LOS)
Alarm Indication Signal (AIS)
•
Analog Loss Of Signal is declared if the
received signal is more than 20 dB or 40 dB
below nominal for at least 1 ms
•
Declared if fewer than six zeros are detected
during a 3 ms interval
•
•
Digital Loss Of Signal is declared if 192 or 32
consecutive zeros are received
Loss Of Signal (LOS)
•
Analog Loss Of Signal is declared if the
received signal is more than 20 dB or 40 dB
below nominal for at least 1 ms
Output pin indicates LOS and/or loss of
frame alignment
Remote Signaling Multiframe Alarm
Y-bit of the multiframe alignment signal
•
•
Digital Loss Of Signal is declared if 192 or 32
consecutive zeros are received
•
Output pin indicates LOS and/or loss of
frame alignment
15
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Maskable Interrupts
T1/J1 Mode
E1 Mode
HDLC Interrupts
•
•
•
•
•
•
Change of state of terminal
synchronization
•
•
•
•
•
•
•
Change of state of basic
frame alignment
•
•
•
•
Go ahead pattern received
End of packet received
End of packet transmitted
Change of state of multiframe
synchronization
Change of state of multiframe
synchronization
End of packet read from
receive FIFO
Change of received bit
oriented message
Change of state of CRC-4
multiframe synchronization
•
•
•
•
•
Transmit FIFO low
Change of state of reception
of AIS
Change of state of reception
of AIS
Frame abort received
Transmit FIFO underrun
Receive FIFO full
Change of state of reception
of LOS
Change of state of reception
of LOS
Receive FIFO overflow
Reception of a severely
errored frame
Reception of consecutively
errored FASs
•
•
•
•
•
•
Transmit slip
Receive remote signaling
multiframe alarm
Receive slip
•
•
•
•
•
•
•
•
•
•
•
•
Receive slip
Receive framing bit error
Receive CRC-6 error
Receive yellow alarm
Receive FAS error
Receive CRC-4 error
Receive E-bit
Change of receive frame
alignment
Receive AIS in timeslot 16
Line code violation
Receive PRBS error
Receive auxiliary pattern
Receive RAI
•
•
•
•
Receive line code violation
Receive PRBS error
Pulse density violation
Framing bit error counter
overflow
FAS error counter overflow
CRC-4 error counter overflow
•
•
CRC-6 error counter overflow
Out of frame alignment
counter overflow
Out of frame alignment
counter overflow
•
•
Change of frame alignment
counter overflow
•
•
Receive E-bit counter
overflow
Line code violation counter
overflow
Line code violation counter
overflow
•
•
PRBS error counter overflow
•
•
PRBS error counter overflow
PRBS multiframe counter
overflow
PRBS multiframe counter
overflow
•
Multiframes out of alignment
counter overflow
•
•
Change of state of any Sa bit
or Sa nibble
•
•
•
•
Loop code detected
One second timer
Five second timer
Jitter attenuator within 4 bits
of overflow/underflow
•
•
•
One second timer
Receive new bit oriented
message (debounced)
Two second timer
Signaling (CAS) bit change
•
Signaling (AB or ABCD) bit
change
16
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Error Counters
•
•
•
•
All counters can be preset or cleared under software control
Maskable occurrence interrupt
Maskable overflow interrupt
Counters can be latched on one second intervals
T1/J1 Mode
E1 Mode
•
•
•
•
•
•
•
PRBS Error Counter (16-bit)
•
•
•
Errored FAS Counter (8-bit)
E-bit Counter (10-bit)
CRC Multiframe Counter (16-bit)
Framing Bit Error Counter (8-bit)
Line Code Violation / Excessive Zeros
Counter (16-bit)
Out of Frame Alignment Counter (4-bit)
Change of Frame Alignment Counter (4-bit)
Multiframes Out of Sync Counter (8-bit)
•
•
•
CRC-4 Error Counter (16-bit)
PRBS Error Counter (8-bit)
CRC Multiframe Counter (8-bit)
Line Code Violation / Excessive Zeros
Counter (16-bit)
•
CRC-6 Error Counter (16-bit)
Error Insertion
T1/J1 Mode
Bipolar Violations
E1 Mode
Bipolar Violations
CRC-4 Errors
•
•
•
•
•
•
•
•
•
•
•
•
CRC-6 Errors
Ft Errors
FAS Errors
Fs Errors
NFAS Errors
Payload Errors
Payload Errors
Loss of Signal Error
Loss of Signal Error
Loopbacks
•
•
•
•
•
•
•
Digital loopback
Remote loopback
ST-BUS loopback
Payload loopback
Metallic loopback
Local timeslot loopback
Remote timeslot loopback
Per Timeslot Control
The following features can be controlled on a per timeslot basis:
•
•
•
•
•
•
•
•
Clear Channel Capability (only used in T1/J1)
Choice of sourcing transmit signaling bits from microport or CSTi pin
Remote timeslot loopback
Local timeslot loopback
PRBS insertion and reception
Digital milliwatt pattern insertion
Per channel inversion
Transmit message mode
17
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Table of Contents
1.0 MT9076 Line Interface Unit (LIU) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
1.1 Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
1.2 Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
1.3 20 MHz Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
1.4 Phase Lock Loop (PLL). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
2.0 Clock Jitter Attenuation Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
2.1 Jitter Attenuator FIFO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
2.2 IMA Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
2.2.1 T1 Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
2.2.2 E1 Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
3.0 The Digital Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
3.1 T1 Digital Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
3.2 Frame and Superframe Structure in T1 Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
3.2.1 Multiframing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
3.3 E1 Digital Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32
3.3.1 Basic Frame Alignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
3.3.2 CRC-4 Multiframing in E1 Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
3.3.3 CAS Signaling Multiframing in E1 Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
4.0 MT9076 Access and Control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
4.1 The Control Port Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
4.2 Control and Status Register Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36
4.3 Identification Code. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
4.3.1 ST-BUS Streams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
5.0 Reset Operation (Initialization) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
6.0 Transmit Data All Ones (TxAO) Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
7.0 Data Link Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
7.1 Data Link Operation in E1 Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
7.2 Data Link Operation in T1 Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
7.2.1 External Data Link . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
7.2.2 Bit - Oriented Messaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
8.0 Floating HDLC Channels. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
8.1 Channel Assignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
8.2 HDLC Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
8.2.1 HDLC Frame Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
8.2.2 Data Transparency (Zero Insertion/Deletion). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
8.2.3 Invalid Frames . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
8.2.4 Frame Abort . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
8.2.5 Interframe Time Fill and Link Channel States . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
8.2.6 Go-Ahead. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
8.3 HDLC Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
8.3.1 HDLC Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
8.3.2 HDLC Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
9.0 Slip Buffers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
9.1 Slip Buffer in T1 Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
9.2 Slip Buffer in E1 Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
10.0 Framing Algorithm. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
10.1 Frame Alignment in T1 Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
10.2 Frame Alignment in E1 Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
10.2.1 Notes for Synchronization State Diagram (Figure 14) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
10.3 Reframe. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
10.3.1 E1 Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
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10.3.2 T1 Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
11.0 MT9076 Channel Signaling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
11.1 Channel Signaling in T1 Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
11.2 Channel Signaling in E1 Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
12.0 Loopbacks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
13.0 Performance Monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
13.1 Error Counters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
13.2 T1 Counters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
13.2.1 Framing Bit Error Counter (FC7-0). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
13.2.2 Out Of Frame/Change Of Frame Alignment Counter (OOF3-0/COFA3-0) . . . . . . . . . . . . . . . . . . 55
13.2.3 Multiframes out of Sync Counter (MFOOF7-MFOOF0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
13.2.4 CRC-6 Error Counter (CC15-0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
13.2.5 Line Code Violation Error Counter (LCV15-LCV0). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
13.2.6 PRBS Error Counter (PS7-0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
13.2.7 CRC Multiframe Counter for PRBS (PSM7-0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
13.3 E1 Counters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
13.4 Errored FAS Counter (EFAS7-EFAS0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
13.5 E-bit Counter (EC15-0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
13.6 Line Code Violation Error Counter (LCV15-LCV0) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
13.7 CRC-4 Error Counter (CC15-0). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
13.8 PRBS Error Counter (PS7-0). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
13.9 CRC Multiframe Counter for PRBS (PSM7-0). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
14.0 Error Insertion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
15.0 Per Time Slot Control Words . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
15.1 Clear Channel Capability. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
15.2 Microport Signaling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
15.3 Per Time Slot Looping. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
15.4 PRBS Testing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
15.5 Digital Milliwatt. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59
15.6 Per Channel Inversion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
15.7 Transmit Message. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
16.0 Alarms. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
16.1 Automatic Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
17.0 Detected Events. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
17.1 T1 Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
17.1.1 Severely Errored Frame Event. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
17.1.2 Loop Code Detect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
17.1.3 Pulse Density Violation Detect. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
17.1.4 Timer Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
17.2 E1 mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
17.2.1 Consecutive Frame Alignment Patterns (CONFAP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
17.2.2 Receive Frame Alignment Signals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
17.2.3 Receive Non Frame Alignment Signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
17.2.4 Receive Multiframe Alignment Signals. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
18.0 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
18.1 Interrupts on T1 Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
18.2 Interrupts on E1 Mode. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
19.0 Digital Framer Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
19.1 T1 Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
19.2 E1 mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
20.0 Control and Status Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
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Table of Contents
20.1 T1 Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
20.1.1 Master Control 1 (Page 01H) (T1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
20.1.2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Master Control 2 (Page 02H) (T1)78
20.1.3 Master Status 1 (Page03H) (T1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
20.1.4 Master Status 2 (Page 04H) (T1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
20.1.5 Per Channel Transmit Signalling (Pages 5 and 6) (T1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
20.2 Per Time Slot Control Words (Pages 7 and 8) (T1). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
20.2.1 Per Channel Receive Signaling (T1 and E1 mode) (Pages 9 and 0AH) . . . . . . . . . . . . . . . . . . . 100
20.3 E1 Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
20.3.1 Master Control 1 (Page 01H) (E1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
20.4 Master Control 2 (Page-2). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
20.4.1 Master Control 2 (Page 02H) (E1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
20.5 Master Status 1 (Page 03H) (E1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
21.0 Master Status 2 (Page-4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
21.1 Master Status 2 (Page 04H) (E1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
21.2 Per Channel Transmit signaling (Pages 5 and 6) (E1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138
21.3 Per Time Slot Control Words (Pages 7 and 8) (E1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
21.4 Per Channel Receive signaling (Pages 9 and 0AH) (E1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
22.0 HDLC Control and Status . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142
23.0 Transmit National Bit Buffer (Page 0EH) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153
24.0 Receive National Bit Buffer (Page 0FH) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 153
25.0 AC/DC Electrical Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154
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Zarlink Semiconductor Inc.
MT9076B
Data Sheet
List of Figures
Figure 1 - MT9076 Functional Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Figure 2 - Pin Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Figure 3 - Input Jitter Tolerance as Recommended by TR-62411 (T1). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Figure 4 - Input Jitter Tolerance as Recommended by G.823 and ETSI 300 011 (E1) . . . . . . . . . . . . . . . . . . . . . 23
Figure 5 - Analog Line Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Figure 6 - Pulse Template (T1.403)(T1). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Figure 7 - Pulse Template (G.703)(E1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Figure 8 - Clock Oscillator Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Figure 9 - Crystal Oscillator Circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Figure 10 - TR 62411 Jitter Attenuation Curve. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Figure 11 - Read and Write Pointers in the Transmit Slip Buffers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Figure 12 - Read and Write Pointers in the Receive Slip Buffers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Figure 13 - Read and Write Pointers in the Slip Buffers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Figure 14 - Synchronization State Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Figure 15 - Motorola Microport Timing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155
Figure 16 - Intel Microport Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156
Figure 17 - JTAG Port Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
Figure 18 - Transmit Data Link Timing Diagram (T1 mode). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158
Figure 19 - Transmit Data Link Timing Diagram (E1 mode). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158
Figure 20 - Transmit Data Link Functional Timing (E1 mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159
Figure 21 - Receive Data Link Functional Timing (T1 mode). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159
Figure 22 - Receive Data Link Diagram (T1 mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160
Figure 23 - Receive Data Link Functional Timing (E1 mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 160
Figure 24 - Receive Data Link Timing Diagram (E1 mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161
Figure 25 - ST-BUS Functional Timing Diagram - 2.048 Mb/s Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 161
Figure 26 - ST-BUS Functional Timing Diagram - 8.192 Mb/s Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162
Figure 27 - ST-BUS Timing Diagram (Input Clocks) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162
Figure 28 - ST-BUS Timing Diagram (Output Clocks) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163
Figure 29 - Receive Multiframe Functional Timing (T1 mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163
Figure 30 - Receive Multiframe Functional Timing (E1 mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164
Figure 31 - Transmit Multiframe Functional Timing (T1 mode or E1 mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164
Figure 32 - Multiframe Timing Diagram (T1 mode or E1 mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164
Figure 33 - TXA/TXB Functional Timing (T1 mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165
Figure 34 - TXA/TXB Functional Timing (E1 mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165
Figure 35 - TXA/TXB Timing Diagram (T1 mode or E1 mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 165
Figure 36 - Tx IMA Functional Timing (T1 mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166
Figure 37 - Rx IMA Functional Timing (T1 mode). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166
Figure 38 - Tx IMA Functional Timing (E1 mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167
Figure 39 - Rx IMA Functional Timing (E1 mode). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167
Figure 40 - Tx IMA Timing Diagram (T1 mode or E1 mode). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167
Figure 41 - Rx IMA Timing Diagram (T1 mode or E1 mode) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168
Figure 42 - D4 Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168
Figure 43 - PCM 30 Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168
Figure 44 - ST-BUS Stream Format - 2.048 Mb/s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169
Figure 45 - ST-BUS Stream Format 8.192 Mb/s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 169
21
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
1.0 MT9076 Line Interface Unit (LIU)
1.1 Receiver
The receiver portion of the MT9076 LIU consists of an input signal peak detector, an optional equalizer with
separate high pass sections, a smoothing filter, data and clock slicers and a clock extractor. Receive equalization
gain can be set manually (i.e., software) or it can be determined automatically by peak detectors.
The output of the receive equalizer is conditioned by a smoothing filter and is passed on to the clock and data slicer.
The clock slicer output signal drives a phase locked loop, which generates an extracted clock (Exclk). This
extracted clock is used to sample the output of the data comparator.
In T1 mode, the receiver portion of the LIU can recover clock and data from the line signal for loop lengths of 0 -
6000 ft. of 22 AWG cable and tolerate jitter to the maximum specified by AT&T TR 62411(Figure 3).
The LOS output pin function is selectable to indicate any combination of loss of signal and/or loss of basic frame
synchronization condition.
The LLOS (Loss of Signal) status bit indicates when the receive signal level is lower than the analog threshold for at
least 1 millisecond, or when the number of consecutive received zeros exceeds the digital loss threshold.
In E1 mode, the analog threshold is either of -20 dB or -40 dB. The digital loss threshold is either 32 or 192.
In T1 mode, the receive LIU circuit requires a terminating resistor of 100 across the device side of the receive 1:1
transformer.
In E1 mode, the receive LIU circuit requires a terminating resistor of either 120 or 75 across the device side of
the receive 1:1 transformer.
The jitter tolerance of the clock extractor circuit exceeds the requirements of TR 62411 in T1 mode (see Figure 3)
and G.823 in E1 mode (see Figure 4).
Peak to Peak
Jitter Amplitude
(log scale)
138UI
100UI
28UI
10UI
1.0UI
0.4UI
Jitter Frequency
(log scale)
0.1 Hz 1.0 Hz
10 Hz
4.9 Hz
100 Hz 1.0 kHz 10 kHz 10 0kHz
Figure 3 - Input Jitter Tolerance as Recommended by TR-62411 (T1)
22
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Peak to Peak
Jitter Amplitude
(log scale)
18UI
MT9076
Tolerance
1.5UI
0.2UI
Jitter Frequency
(log scale)
1.667 Hz
20 Hz
2.4 kHz 18 kHz 100 kHz
Figure 4 - Input Jitter Tolerance as Recommended by G.823 and ETSI 300 011 (E1)
1.2 Transmitter
The transmit portion of the MT9076 LIU consists of a high speed digital-to-analog converter and complementary
line drivers.
When a pulse is to be transmitted, a sequence of digital values (dependent on transmit equalization) are read out of
a ROM by a high speed clock. These values drive the digital-to-analog converter to produce an analog signal,
which is passed to the complementary line drivers.
The complementary line drivers are designed to drive a 1:2.4 step-up transformer in T1 mode and either a 1:2 or
1:2.4 step-up transformer in E1 mode (see Figure 5). A 0.47 uF capacitor is required between the TTIP and the
transmit transformer. Resistors RT (as shown in Figure 5) are for termination for transmit return loss. The values of
RT may be optimized for T1 mode, E1 120 lines, E1 75 lines or set at a compromise value to serve multiple
applications. Program the Tx LIU Control Word (page 02H, address 11H) to adjust the pulse amplitude accordingly.
Alternatively, the pulse level and shape may be discretely programmed by writing to the Custom Pulse Level
registers (page 2, addresses 1CH to 1FH) and setting the Custom Transmit Pulse bit high (bit 3 of the Tx LIU
Control Word). In this case the output of each of the registers directly drives the D/A converter going to the line
driver. Table 1 and Table 2 show recommended transmit pulse amplitude settings.
In T1 mode, the template for the transmitted pulse (the DSX-1 template) is shown in Figure 6. The nominal peak
voltage of a mark is 3 volts. The ratio of the amplitude of the transmit pulses generated by TTIP and TRING lie
between 0.95 and 1.05.
In E1 mode, the template for the transmitted pulse, as specified in G.703, is shown in Figure 7. The nominal peak
voltage of a mark is 3 volts for 120 twisted pair applications and 2.37 volts for 75 coax applications. The ratio of
the amplitude of the transmit pulses generated by TTIP and TRING lie between 0.95 and 1.05.
23
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
RT
RT
1:2.4
0.47 uF
Tx
TTIP
TRING
RTIP
R : refer to datasheet
T
1:1
100
120
75
RRING
Rx
Figure 5 - Analog Line Interface
Notes:
1)
Protection circuitry (i.e., voltage clamps, line fuses, common mode choke etc.) depends on the
application and is not shown. For a reference design, refer to the evaluation board schematic.
2)
The transformer shown is a Pulse Engineering T1144.
Name
Functional Description
TXL2-0 Transmit Line Build Out 2 - 0. Setting these bits shapes the transmit pulse as detailed in the table
below:
TXL2
TXL1
TXL0
Line Build Out
0 to 133 feet/ 0 dB
133 to 266 feet
266 to 399 feet
399 to 533 feet
533 to 655 feet
-7.5 dB
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
-15 dB
-22.5 dB
After reset these bits are zero.
Table 1 - Transmit Line Build Out (T1)
24
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Name
Functional Description
WR
Winding Ratio. Set this pin low if a 1:2.4 transformer is used on the transmit side. Set this pin high
if a 1:2 transformer is used.
TX2-0
Transmit pulse amplitude. Select the TX2 –TX0 bits according to the line type, value of
termination resistors (RT), and transformer turns ratio used.
TX2 TX1 TX0
Line Impedance (ohms)
RT(ohms)
Transformer Ratio
WR (bit 7)
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
120
120
120
75
-
75
0
6.8
6.8
5.1
-
6
6
5.1
1:2.4
1:2.4
1:2.4
1:2.4
-
1:2
1:2
1:2.4
0
0
0
0
-
1
1
0
75
75
After reset, these bits are zero.
Table 2 - Transmit Pulse Amplitude (E1)
1.20
1.05
0.95
0.90
0.80
0.50
0.05
0
-0.05
-0.26
-0.45
Time, in unit intervals (UI)
NOTE: 1 Unit Interval = 648 nanoseconds
Figure 6 - Pulse Template (T1.403)(T1)
25
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Time (Nanoseconds)
Time U.I.
-499 -253 -175 -175 -78
-.77 -.39 -.27 -.27 -.12
0
0
175 220 499 752 ---
.27 .34 .77 1.16 ---
.05 ---
---
---
---
Normalized Amplitude
.05
.05
.8
1.2
1.2
1.05 1.05 -.05 .05
Table 3 - Maximum Curve for Figure 5
Time (Nanoseconds)
Time U.I.
-499 -149 -149 -97
-.77 -.23 -.23 -.15
0
97
.15
.9
149 149 298 395 603 752
0
.23
.5
.23
.46
.61
.93
1.16
Normalized Amplitude
-.05 -.05 .5
.9
.95
-.45 -.45 -.26 -.05 -.05
Table 4 - Minimum Curve for Figure 5
Percentage of Nominal
Peak Voltage
269 ns
120
110
100
90
244 ns
194 ns
80
50
20
0
-10
-20
Nominal Pulse
219 ns
488 ns
Figure 7 - Pulse Template (G.703)(E1)
26
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
1.3 20 MHz Clock
The MT9076 requires a 20 MHz clock. This may be provided by a 50 ppm oscillator as per Figure 8.
+3.3 V
Vdd
20 MHz
OUT
OSC1
OSC2
.1 F
GND
(open)
Figure 8 - Clock Oscillator Circuit
Alternatively, a crystal oscillator may be used. A complete oscillator circuit made up of a crystal, resistors and
capacitors is shown in Figure 9. The crystal specification is as follows.
Frequency:
20 MHz
50 ppm
Fundamental
Parallel
32 pF
Tolerance:
Oscillation Mode:
Resonance Mode:
Load Capacitance:
Maximum Series Resistance:
Approximate Drive Level:
35
1 mW
20 MHz
OSC1
56 pF
39 pF
1M
1 H*
100
OSC2
Note: the 1 H inductor is optional
Figure 9 - Crystal Oscillator Circuit
1.4 Phase Lock Loop (PLL)
The MT9076 contains a PLL, which can be locked to either an input 4.096 MHz clock or the extracted line clock.
The PLL will attenuate jitter from less than 2.5 Hz and roll-off at a rate of 20 dB/decade. Its intrinsic jitter is less than
0.02 UI. The PLL will meet the jitter transfer characteristics as specified by AT&T document TR 62411 and the
relevant recommendations as shown in Figure 3.
27
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
dB
-0.5
0
-20 dB/decade
19.5
10
40
400
10 K
Frequency (Hz)
Figure 10 - TR 62411 Jitter Attenuation Curve
2.0 Clock Jitter Attenuation Modes
MT9076 has three basic jitter attenuation modes of operation, selected by the BS/LS and S/FR/Exclki control pins.
•
•
•
System Bus Synchronous Mode
Line Synchronous Mode
Free-run mode
Depending on the mode selection above, the PLL can either attenuate transmit clock jitter or the receive clock jitter.
Table 5 shows the appropriate configuration of each control pin to achieve the appropriate mode and Jitter
attenuation capability of the MT9076.
Mode Name
BS/LS
S/FR/Exclki
Note
System Bus Synchronous
Line Synchronous
Free-Run
1
0
x
1
1
0
PLL locked to C4b
PLL locked to Exclk
PLL free - running
Table 5 - Selection of Clock Jitter Attenuation Modes using the M/S and MS/FR Pins
In System Bus Synchronous mode, pins C4b and F0b are always configured as inputs, while in the Line
Synchronous and Free-Run modes C4b and F0b are configured as outputs.
Referring to the mode names given in Table 5 the basic operation of the jitter attenuation modes are:
•
In System Bus Synchronous mode an external clock is applied to C4b. The applied clock is dejittered by the
internal PLL before being used to synchronize the transmitted data. The clock extracted (with no jitter
attenuation performed) from the receive data can be monitored on pin Exclk.
28
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
•
•
In Line Synchronous mode, the clock extracted from the receive data is dejittered using the internal PLL and
then output on pin C4b. Pin Exclk provides the extracted receive clock before it has been dejittered. The
transmit data is synchronous to the clean receive clock.
In Free-Run mode the transmit data is synchronized to the internally generated clock. The internal clock is
output on pin C4b. The clock signal extracted from the receive data is not dejittered and is output directly on
Exclk.
2.1 Jitter Attenuator FIFO
In System Bus Synchronous operation, a data buffer is required between the jittered input clock and the clean
transmit clock. In normal T1 mode, the transmit slip buffer performs this function. In T1 IMA mode, the transmit slip
buffer is unused, instead a jitter attenuator FIFO is employed. In an E1 mode System Bus Synchronous
configuration, the jitter attenuator FIFO is always used. In this case the C4b signal clocks the data into the FIFO,
the PLL de-jitters the C4b clock and the resulting clean C4b signal clocks the data out of the FIFO.
The JA meets the jitter transfer characteristics as proposed by ETSI ETS 300 011, G.735 and the relevant
recommendations as shown in Figure 10. The JA FIFO depth can be selected to be from 16 to 128 words deep, in
multiples of 16 (2-bit) words. Its read pointer can be centered by changing the JFC bit (address 13H of page 02H) to
provide maximum jitter tolerance. If the read pointer should come within 4 bits of either end of the FIFO, the read
clock frequency will be increased or decreased by 0.0625 UI to correct the situation. The maximum time needed to
centre is Tmax= 3904Depth ns, where Depth is the selected JA FIFO depth. During this time the JA will not
attenuate jitter.
2.2 IMA Mode
2.2.1 T1 Mode
In T1 IMA Mode, neither the transmit nor the receive slip buffers are activated. Channel Associated signaling (CAS)
and HDLC operation is not supported. The input pin C4b accepts a 1.544 MHz clock and it clocks incoming data
from DSTi into a jitter attenuator FIFO. This clock is dejittered with the internal PLL. The dejittered clock clocks data
out of the FIFO for transmission onto the line. Receive clock (1.544 MHz) and data is extracted from the line and
routed to pins Exclk and DSTo respectively. The receive clock Exclk is not dejittered before being driven off chip.
For operation in IMA mode, the MT9076 should be programmed in System Bus Synchronous mode (BS/LS and
S/FR/Exclki set high).
2.2.2 E1 Mode
In E1 IMA Mode neither the transmit nor the receive slip buffers are activated. The input pin C4b accepts a
2.048 MHz clock and it clocks incoming data from DSTi into a jitter attenuator FIFO. This clock is dejittered with the
internal PLL. The dejittered clock clocks data out of the FIFO for transmission onto the line. Receive clock
(2.048 MHz) and data is extracted from the line and routed to pins Exclk and DSTo respectively. The receive clock
Exclk is not dejittered before being driven off chip. For operation in IMA mode, the MT9076 should be programmed
in System Bus Synchronous mode (BS/LS and S/FR/Exclki set high).
3.0 The Digital Interface
3.1 T1 Digital Interface
In T1 mode, DS1 frames are 193 bits long and are transmitted at a frame repetition rate of 8000 Hz, which results in
an aggregate bit rate of 193 bits x 8000/sec= 1.544 Mbits/sec. The actual bit rate is 1.544 Mbits/sec +/-50 ppm
optionally encoded in B8ZS format. The Zero Suppression control register (page 1, address 15H,) selects either
B8ZS encoding, forced one stuffing or alternate mark inversion (AMI) encoding. Basic frames are divided into 24
time slots numbered 1 to 24. Each time slot is 8 bits in length and is transmitted most significant bit first (numbered
bit 1). This results in a single time slot data rate of 8 bits x 8000/sec. = 64 kbits/sec.
29
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
It should be noted that the Zarlink ST-BUS has 32 channels numbered 0 to 31. When mapping to the DS1 payload
only the first 24 time slots and the last (time slot 31, for the overhead bit) of an ST-BUS are used (see Table 6). All
unused channels are tristate.
When signaling information is written to the MT9076 in T1 mode using ST-BUS control links (as opposed to direct
writes by the microport to the on - board signaling registers), the CSTi channels corresponding to the selected DSTi
channels streams are used to transmit the signaling bits.
Since the maximum number of signaling bits associated with any channel is 4 (in the case of ABCD), only half a
CSTi channel is required for sourcing the signaling bits. The choice of which half of the channel to use is selected
by the control bit MSN (page 01H address 14H). The same control bit selects which half of the CSTo channel will
contain receive signaling information (the other nibble in the channel being tristate). Unused channels are tristate.
The most significant bit of an eight bit ST-BUS channel is numbered bit 7 (see Zarlink Application Note MSAN-126).
Therefore, ST-BUS bit 7 is synonymous with DS1 bit 1; bit 6 with bit 2: and so on.
DS1 Timeslots
1
0
2
1
3
2
4
3
5
4
6
5
7
6
8
7
9
8
10 11 12 13 14 15
16
15
Voice/Data Channels
(DSTi/o and CSTi/o)
9
10 11 12 13 14
DS1 Timeslots
17 18 19 20 21 22 23 24
-
-
-
-
-
-
-
-
Voice/Data Channels
(DSTi/o and CSTi/o)
16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
31
Sbit
x
x
x
x
x
x
x
Table 6 - ST-BUS vs. DS1 to Channel Relationship(T1)
3.2 Frame and Superframe Structure in T1 Mode
3.2.1 Multiframing
In T1 mode, DS1 trunks contain 24 bytes of serial voice/data channels bundled with an overhead bit. The frame
overhead bit contains a fixed repeating pattern used to enable DS1 receivers to deliniate frame boundaries.
Overhead bits are inserted once per frame at the beginning of the transmit frame boundary. The DS1 frames are
further grouped in bundles of frames, generally 12 (for D4 applications) or 24 frames (for ESF - extended
superframe applications) deep. Table 7 and Table 8 illustrate the D4 and ESF frame structures respectively.
For D4 links the frame structure contains an alternating 101010... pattern inserted into every second overhead bit
position. These bits are intended for determination of frame boundaries, and they are referred to as Ft bits. A
separate fixed pattern, repeating every superframe, is interleaved with the Ft bits. This fixed pattern (001110), is
used to deliniate the 12 frame superframe. These bits are referred to as the Fs bits. In D4 frames # 6 and #12, the
LSB of each channel byte may be replaced with A bit (frame #6) and B bit (frame #12) signaling information.
For ESF links the 6 bit framing pattern 001011, inserted into every 4th overhead bit position, is used to deliniate
both frame and superframe boundaries. Frames #6, 12, 18 and 24 contain the A, B, C and D signaling bits,
respectively. A 4 kHz data link is embedded in the overhead bit position, interleaved between the framing pattern
sequence (FPS) and the transmit CRC-6 remainder (from the calculation done on the previous superframe), see
Table 8.
The SLC-96 frame structure is similar to the D4 frame structure, except a facility management overlay is
superimposed over the erstwhile Fs bits, see Table 9.
The protocol appropriate for the application is selected via the Framing Mode Selection Word, address 10H of
Master Control page 1. In T1 mode, MT9076 is capable of generating the overhead bit framing pattern and (for ESF
links) the CRC remainder for transmission onto the DS1 trunk. The beginning of the transmit multiframe may be
determined by any of the following criteria:
30
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
(i) It may free - run with the internal multiframe counters;
(ii) The multiframe counters may be reset with the external hardware pin TxMF. If this signal is not synchronous
with the current transmit frame count it may cause the far end to go temporarily out of sync.
(iii) Under software control (by setting the TxSYNC bit in page 01 address 12H) the transmit multiframe
counters will be synchronized to the framing pattern present in the overhead bits multiplexed into channel
31 bit 0 of the incoming 2.048 Mb/s digital stream DSTi. Note that the overhead bits extracted from the
receive signal are multiplexed into outgoing DSTo channel 31 bit 0.
(iv) In SLC - 96 mode the transmit frame counters synchronize to the framing pattern clocked in on the TXDL
input
Frame #
Ft
Fs
Signaling
1
2
1
0
0
1
1
1
0
3
0
1
0
1
0
4
5
6
A
B
7
8
9
10
11
12
Table 7 - D4 Superframe Structure(T1)
Frame #
FPS
FDL
CRC
Signaling
1
2
X
CB1
3
X
X
X
X
X
X
X
X
X
4
0
0
1
0
1
5
6
CB2
CB3
CB4
CB5
A
B
C
7
8
9
10
11
12
13
14
15
16
17
18
19
20
Table 8 - ESF Superframe Structure (T1)
31
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Frame #
FPS
FDL
CRC
Signaling
21
22
23
24
X
CB6
X
1
D
Table 8 - ESF Superframe Structure (T1) (continued)
Frame # Ft
Fs Notes Frame # Ft
Fs Notes Frame # Ft
Fs
Notes
1
2
1
0
1
0
1
0
1
0
1
0
1
0
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
1
0
1
0
1
0
1
0
1
0
1
0
C
o
n
c
e
n
t
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
1
0
1
0
1
0
1
0
1
0
1
0
0
0
0
1
1
1
0
0
0
1
1
1
R
e
s
y
n
c
h
r
X
X
X
X
X
X
X
X
X
X
X
S
S
S
C
C
C
A
A
L
S = Spoiler Bits
3
4
5
6
C = Maintenance Field Bits
7
8
r
9
a
t
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
o
n
i
o
r
A = Alarm Field Bits
z
a
t
F
i
i
e
l
L = Line Switch Field Bits
o
n
d
L
d
a
t
B
i
L
t
L
a
s
S
S = Spoiler Bits
Table 9 - SLC-96 Framing Structure(T1)
3.3 E1 Digital Interface
PCM 30 (E1) basic frames are 256 bits long and are transmitted at a frame repetition rate of 8000 Hz, which results
in an aggregate bit rate of 256 bits x 8000/sec = 2.048 Mbits/sec. The actual bit rate is 2.048 Mbits/sec +/-50 ppm
encoded in HDB3 format. The HDB3 control bit (page 01H, address 15H, bit 5) selects either HDB3 encoding or
alternate mark inversion (AMI) encoding. Basic frames are divided into 32 time slots numbered 0 to 31, see
Figure 43 on page 168. Each time slot is 8 bits in length and is transmitted most significant bit first (numbered bit 1).
This results in a single time slot data rate of 8 bits x 8000/sec. = 64 kbits/sec.
It should be noted that the Zarlink ST-BUS also has 32 channels numbered 0 to 31, but the most significant bit of an
eight bit channel is numbered bit 7 (see Zarlink Application Note MSAN-126). Therefore, ST-BUS bit 7 is
synonymous with PCM 30 bit 1; bit 6 with bit 2: and so on (Figure 44).
PCM 30 time slot 0 is reserved for basic frame alignment, CRC-4 multiframe alignment and the communication of
maintenance information. In most configurations time slot 16 is reserved for either Channel Associated signaling
32
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
(CAS or ABCD bit signaling) or Common Channel signaling (CCS). The remaining 30 time slots are called channels
and carry either PCM encoded voice signals or digital data. Channel alignment and bit numbering is consistent with
time slot alignment and bit numbering. However, channels are numbered 1 to 30 and relate to time slots as per
Table 10.
PCM 30 Timeslots
0
0
1,2,3...15
1,2,3...15
16 17,18,19,... 31
16 17,18,19,... 31
Voice/Data Channels
(DSTi/o and CSTi/o)
Table 10 - ST-BUS vs. PCM-30 to Channel Relationship(E1)
3.3.1 Basic Frame Alignment
Time slot 0 of every basic frame is reserved for basic frame alignment and contains either a Frame Alignment
Signal (FAS) or a Non-Frame Alignment Signal (NFAS). FAS and NFAS occur in time slot zero of consecutive basic
frames as shown in Table 10. Bit two is used to distinguish between FAS (bit two = 0) and NFAS (bit two = 1).
Basic frame alignment is initiated by a search for the bit sequence 0011011 which appears in the last seven bit
positions of the FAS, see the Frame Algorithm section. Bit position one of the FAS can be either a CRC-4 remainder
bit or an international usage bit.
Bits four to eight of the NFAS (i.e., Sa4 - Sa8) are additional spare bits which may be used as follows:
•
Sa4 to Sa8 may be used in specific point-to-point applications (e.g., transcoder equipments conforming to
G.761)
•
•
Sa4 may be used as a message-based data link for operations, maintenance and performance monitoring
S
a5 to Sa8 are for national usage
A maintenance channel or data link at 4,8,12,16,or 20 kHz for selected Sa bits is provided by the MT9076 in E1
mode to implement these functions. Note that for simplicity all Sa bits including Sa4 are collectively called national
bits throughout this document.
Bit three (designated as “A”), the Remote Alarm Indication (RAI), is used to indicate the near end basic frame
synchronization status to the far end of a link. Under normal operation, the A (RAI) bit should be set to 0, while in
alarm condition, it is set to 1.
Bit position one of the NFAS can be either a CRC-4 multiframe alignment signal, an E-bit or an international usage
bit. Refer to an approvals laboratory and national standards bodies for specific requirements.
33
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
PCM 30 Channel Zero
CRC
Frame/Type
CRC
1
2
3
4
5
6
7
8
0/FAS
C1
0
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
A
0
1
Sa4
1
1
Sa5
1
0
Sa6
0
1
Sa7
1
1
Sa8
1
1/NFAS
2/FAS
C2
0
3/NFAS
4/FAS
A
0
Sa4
1
Sa5
1
Sa6
0
Sa7
1
Sa8
1
C3
1
5/NFAS
6/FAS
A
0
Sa4
1
Sa5
1
Sa6
0
Sa7
1
Sa8
1
C4
0
7/NFAS
8/FAS
A
0
Sa4
1
Sa5
1
Sa6
0
Sa7
1
Sa8
1
C1
1
9/NFAS
10/FAS
11/NFAS
12/FAS
13/NFAS
14/FAS
15/NFAS
A
0
Sa4
1
Sa5
1
Sa6
0
Sa7
1
Sa8
1
C2
1
A
0
Sa4
1
Sa5
1
Sa6
0
Sa7
1
Sa8
1
C3
E1
C4
E2
A
0
Sa4
1
Sa5
1
Sa6
0
Sa7
1
Sa8
1
A
Sa4
Sa5
Sa6
Sa7
Sa8
Table 11 - FAS and NFAS Structure
indicates position of CRC-4 multiframe alignment signa
3.3.2 CRC-4 Multiframing in E1 Mode
The primary purpose for CRC-4 multiframing is to provide a verification of the current basic frame alignment,
although it can also be used for other functions such as bit error rate estimation. The CRC-4 multiframe consists of
16 basic frames numbered 0 to 15, and has a repetition rate of 16 frames X 125 microseconds/frame = 2 msec.
CRC-4 multiframe alignment is based on the 001011 bit sequence, which appears in bit position one of the first six
NFASs of a CRC-4 multiframe.
The CRC-4 multiframe is divided into two submultiframes, numbered 1 and 2, which are each eight basic frames or
2048 bits in length.
The CRC-4 frame alignment verification functions as follows. Initially, the CRC-4 operation must be activated and
CRC-4 multiframe alignment must be achieved at both ends of the link. At the local end of a link, all the bits of every
transmit submultiframe are passed through a CRC-4 polynomial (multiplied by X4 then divided by X4 + X + 1), which
generates a four bit remainder. This remainder is inserted in bit position one of the four FASs of the following
submultiframe before it is transmitted (see Table 12).
The submultiframe is then transmitted and, at the far end, the same process occurs. That is, a CRC-4 remainder is
generated for each received submultiframe. These bits are compared with the bits received in position one of the
four FASs of the next received submultiframe. This process takes place in both directions of transmission.
When more than 914 CRC-4 errors (out of a possible 1000) are counted in a one second interval, the framing
algorithm will force a search for a new basic frame alignment. See Frame Algorithm section for more details.
The result of the comparison of the received CRC-4 remainder with the locally generated remainder will be
transported to the far end by the E-bits. Therefore, if E1 = 0, a CRC-4 error was discovered in a submultiframe 1
received at the far end; and if E2 = 0, a CRC-4 error was discovered in a submultiframe 2 received at the far end.
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Zarlink Semiconductor Inc.
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Data Sheet
No submultiframe sequence numbers or re-transmission capabilities are supported with layer 1 PCM 30 protocol.
See ITU-T G.704 and G.706 for more details on the operation of CRC-4 and E-bits.
There are two CRC multiframe alignment algorithm options selected by the AUTC control bit (address 10H, page
01H). When AUTC is zero, automatic CRC-to-non-CRC interworking is selected. When AUTC is one and ARAI is
low, if CRC-4 multiframe alignment is not found in 400 msec, the transmit RAI will be continuously high until CRC-4
multiframe alignment is achieved.
The control bit for transmit E bits (TE, address 11H of page 01H) will have the same function in both states of
AUTC. That is, when CRC-4 synchronization is not achieved the state of the transmit E-bits will be the same as the
state of the TE control bit. When CRC-4 synchronization is achieved the transmit E-bits will function as per ITU-T
G.704. Table 12 outlines the operation of the AUTC, ARAI and TALM control bits of the MT9076.
AUTC
ARAI
TALM
Description
0
0
X
Automatic CRC-interworking is activated. If no valid CRC MFAS is being
received, transmit RAI will flicker high with every reframe (8 msec.), this cycle will
continue for 400 msec., then transmit RAI will be low continuously. The device will
stop searching for CRC MFAS, continue to transmit CRC-4 remainders, stop
CRC-4 processing, indicate CRC-to-non-CRC operation and transmit E-bits to be
the same state as the TE control bit (page 01H, address 16H).
0
0
1
1
1
0
0
1
X
Automatic CRC-interworking is activated. Transmit RAI is low continuously.
Automatic CRC-interworking is activated. Transmit RAI is high continuously.
Automatic CRC-interworking is de-activated. If no valid CRC MFAS is being
received, transmit RAI flickers high with every reframe (8 msec.), this cycle
continues for 400 msec, then transmit RAI becomes high continuously. The
device continues to search for CRC MFAS and transmit E-bits are the same state
as the TE control bit. When CRCSYN = 0, the CRC MFAS search is terminated
and the transmit RAI goes low.
1
1
1
1
0
1
Automatic CRC-interworking is de-activated. Transmit RAI is low continuously.
Automatic CRC-interworking is de-activated. Transmit RAI is high continuously.
Table 12 - Operation of AUTC, ARAI and TALM Control Bits (E1 Mode)
3.3.3 CAS Signaling Multiframing in E1 Mode
The purpose of the signaling multiframing algorithm is to provide a scheme that will allow the association of a
specific ABCD signaling nibble with the appropriate PCM 30 channel. Time slot 16 is reserved for the
communication of Channel Associated signaling (CAS) information (i.e., ABCD signaling bits for up to 30 channels).
Refer to ITU-T G.704 and G.732 for more details on CAS multiframing requirements.
A CAS signaling multiframe consists of 16 basic frames (numbered 0 to 15), which results in a multiframe repetition
rate of 2 msec. It should be noted that the boundaries of the signaling multiframe may be completely distinct from
those of the CRC-4 multiframe. CAS multiframe alignment is based on a multiframe alignment signal (a 0000 bit
sequence), which occurs in the most significant nibble of time slot 16 of basic frame 0 of the CAS multiframe. Bit 6
of this time slot is the multiframe alarm bit (usually designated Y). When CAS multiframing is acquired on the
receive side, the transmit Y-bit is zero; when CAS multiframing is not acquired, the transmit Y-bit is one. Bits 5, 7
and 8 (usually designated X) are spare bits and are normally set to one if not used.
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Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Time slot 16 of the remaining 15 basic frames of the CAS multiframe (i.e., basic frames 1 to 15) are reserved for the
ABCD signaling bits for the 30 payload channels. The most significant nibbles are reserved for channels 1 to 15 and
the least significant nibbles are reserved for channels 16 to 30. That is, time slot 16 of basic frame 1 has ABCD for
channel 1 and 16, time slot 16 of basic frame 2 has ABCD for channel 2 and 17, through to time slot 16 of basic
frame 15 has ABCD for channel 15 and 30.
4.0 MT9076 Access and Control
4.1 The Control Port Interface
The control and status registers of the MT9076 are accessible through a non-multiplexed parallel microprocessor
port. The parallel port may be configured for Motorola style control signals (by setting pin INT/MOT low) or Intel
style control signals (by setting pin INT/MOT high).
4.2 Control and Status Register Access
The controlling microprocessor gains access to specific registers of the MT9076 through a two step process.
First, writing to the Command/Address Register (CAR) selects one of the 15 pages of control and status
registers (CAR address: AC4 = 0, AC3-AC0 = don't care, CAR data D7 - D0 = page number). Second, each
page has a maximum of 16 registers that are addressed on a read or write to a non-CAR address (non-CAR:
address AC4 = 1, AC3-AC0 = register address, D7-D0 = data). Once a page of memory is selected, it is only
necessary to write to the CAR when a different page is to be accessed. See the AC Electrical Characteristics
section.
Page Address D7 - D0
Register Description
Processor Access
ST-BUS Access
00000001 (01H)
00000010 (02H)
00000011 (03H)
00000100 (04H)
00000101 (05H)
00000110 (06H)
00000111 (07H)
00001000 (08H)
00001001 (09H)
00001010 (0AH)
00001011 (0BH)
00001011 (0CH)
00001011 (0DH)
00001011 (0EH)
00001011 (0FH)
Master
Control
R/W
R/W
R
- - -
Master
Status
- - -
R/W
R/W
R/W
Per Channel Transmit signaling
Per Channel Transmit signaling
Per Time Slot Control
CSTi
CSTi
- - -
- - -
CSTo
CSTo
- -
Per Time Slot Control
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R
Per Channel Receive signaling
Per Channel Receive signaling
HDLC0 Control and Status
HDLC1 Control and Status
HDLC2 Control and Status
Tx National Bit Buffer
- -
- -
- -
Rx National Bit Buffer
- -
Table 13 - Page Summary
Please note that for microprocessors with read/write cycles less than 200 ns, a wait state or a dummy operation (for
C programming) between two successive read/write operations to the HDLC FIFO is required.
Table 13 associates the MT9076 control and status pages with access and page descriptions.
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Zarlink Semiconductor Inc.
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Data Sheet
4.3 Identification Code
The MT9076 shall be identified by the code 01111000, read from the identification code status register (page
03H, address 1FH).
4.3.1 ST-BUS Streams
In T1 mode, there is one control and one status ST-BUS stream that can be used to program / access channel
associated signaling nibbles. CSTo contains the received channel associated signaling bits, and for those channels
whose Per Time Slot Control word bit 1 “RPSIG” is set low, CSTi is used to control the transmit channel associated
signaling. The DSTi and DSTo streams contain the transmit and receive voice and digital data. Only 24 of the 32
ST-BUS channels are used for each of DSTi, DSTo, CSTi and CSTo. In each case individual channel mapping is as
illustrated in Table 6, “ST-BUS vs. DS1 to Channel Relationship(T1),” on page 30.
In E1 mode, ST-BUS streams can also be used to access channel associated signaling nibbles. CSTo contains the
received channel associated signaling bits (e.g., ITU-T R1 and R2 signaling), and for those channels whose Per
Time Slot Control word bit 1 “RPSIG” is set low, CSTi is used to control the transmit channel associated signaling.
The DSTi and DSTo streams contain the transmit and receive voice and digital data.
Only 30 of the 32 ST-BUS channels are used for each of DSTi, DSTo, CSTi and CSTo. In each case individual
channel mapping is as illustrated in Table 10 Time slot to Channel Relationship.
5.0 Reset Operation (Initialization)
The MT9076 can be reset using the hardware RESET pin (pin 11 in PLCC, pin 64 in LQFP) or the software reset bit
RST (page 1H, address 1AH). When the device emerges from its reset state it will begin to function with the default
settings described in Table 14 (T1) Table 15 (E1). All control registers are set to 00H. A reset operation takes 1 full
frame (125 us) to complete.
Function
Status
Mode
Loopbacks
SLC-96
D4
Deactivated
Deactivated
Deactivated
Deactivated
Serial Mode
CAS Registers
Deactivated
masked
Zero Coding
Line Codes
Data Link
signaling
AB/ABCD Bit Debounce
Interrupts
Error Insertion
HDLCs
Deactivated
Deactivated
Cleared
Counters
Transmit Data
All Ones
Table 14 - Reset Status(T1)
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Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Function
Status
Mode
Loopbacks
Termination
Deactivated
Cn0011011
1/Sn1111111
00001111
Transmit FAS
Transmit non-FAS
Transmit MFAS (CAS)
Data Link
Deactivated
Activated
CRC Interworking
signaling
CAS Registers
Deactivated
Masked
ABCD Bit Debounce
Interrupts
RxMF Output
Error Insertion
HDLCs
signaling Multiframe
Deactivated
Deactivated
Cleared
Counters
Transmit Data
All Ones
Table 15 - Reset Status (E1)
6.0 Transmit Data All Ones (TxAO) Operation
The TxAO (Transmit all ones) pin allows the PRI interface to transmit an all ones signal under hardware control.
7.0 Data Link Operation
7.1 Data Link Operation in E1 Mode
In E1 mode, MT9076 has a user defined 4, 8, 12, 16 or 20 kbit/s data link for transport of maintenance and
performance monitoring information across the PCM 30 link. This channel functions using the Sa bits (Sa4~Sa8) of
the PCM 30 timeslot zero non-frame alignment signal (NFAS). Since the NFAS is transmitted every other frame - a
periodicity of 250 microseconds - the aggregate bit rate is a multiple of 4 kb/s. As there are five Sa bits
independently available for this data link, the bit rate will be 4, 8, 12, 16 or 20 kb/s, depending on the bits selected
for the Data Link (DL).
The Sa bits used for the DL are selected by setting the appropriate bits, Sa4~Sa8, to one in the Data Link Select
Word (page 01H, address 17H, bits 4-0). Access to the DL is provided by pins TxDLCLK, TxDL, RxDLCLK and
RxDL, which allow easy interfacing to an external controller.
Data to be transmit onto the line in the Sa bit position is clocked in from the TxDL pin (pin 65 in PLCC, pin 47 in
LQFP) with the clock TxDLCLK (pin 64 in PLCC, pin 46 pin LQFP). Although the aggregate clock rate equals the bit
rate, it has a nominal pulse width of 244 ns, and it clocks in the TxDL as if it were a 2.048 Mb/s data stream. The
clock can only be active during bit times 4 to 0 of the STBUS frame. The TxDL input signal is clocked into the
MT9076 by the rising edge of TxDLCLK. If bits are selected to be a part of the DL, all other programmed functions
for those Sa bit positions are overridden.
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Zarlink Semiconductor Inc.
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Data Sheet
The RxDLCLK signal (pin 39 - PLCC, pin 14 - LQFP) is derived from the receive extracted clock and is aligned with
the receive data link output RxDL. The HDB3 decoded receive data, at 2.048 Mbit/s, is clocked out of the device on
pin RxDL (pin 40 in PLCC, pin 15 in LQFP). In order to facilitate the attachment of this data stream to a Data Link
controller, the clock signal RxDLCLK consists of positive pulses, of nominal width of 244 ns, during the Sa bit cell
times that are selected for the data link.This selection is made by programming address 17H of master control page
01H. No DL data will be lost or repeated when a receive frame slip occurs. See AC Electrical Characteristics for
timing requirements.
7.2 Data Link Operation in T1 Mode
SLC-96 and ESF protocol allow for carrier messages to be embedded in the overhead bit position. The MT9076
provides 3 separate means of controlling these data links. See Data Link Control Word - address 12H, page 1H.
•
•
The data links (transmit and receive) may be sourced (sunk) from an external controller using dedicated pins
on the MT9076 in T1 mode (enabled by setting the bit 7 - EDL of the Data link Control Word).
Bit Oriented Messages may be transmit and received via a dedicated TxBOM register (page 1H, address
13H) and a RxBOM (page 3H, address 15H). Transmission is enabled by setting bit 6 - BIOMEn in the Data
link Control Word. Bit - oriented messages may be periodically interrupted (up to once per second) for a
duration of up to 100 milliseconds. This is to accommodate bursts of message - oriented protocols. See
Table 16 for message structure.
Octet #
8
7
6
5
4
3
2
1
Content
1
2
F
S
L
A
P
G
I
01111110
A
C / R
EA
EA
00111000 or
00111010
3
4
T
E
I
00000001
C
O
N
T
R
U2
R
O
L
00000011
5
G3
FE
G3
FE
G3
FE
G3
FE
LV
SE
LV
SE
LV
SE
LV
SE
G4
LB
G4
LB
G4
LB
G4
LB
U1
G1
U1
G1
U1
G1
U1
G1
G5
G2
G5
G2
G5
G2
G5
G2
SL
G6
NI
t0
t0
6
Nm
SL
7
U2
R
G6
NI
t0-1
8
Nm
SL
t0-1
9
U2
R
G6
NI
t0-2
10
11
12
13
14
Nm
SL
t0-2
U2
R
G6
NI
t0-3
Nm
t0-3
F
C
S
VARIABLE
Table 16 - Message Oriented Performance Report Structure (T1.403 and T1.408)
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Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Note:
ADDRESS
INTERPRETATION
00111000
00111010
00000001
SAPI = 14, C/R = 0 (CI) EA = 0
SAPI = 14, C/R = 1(Carrier) EA = 0
TEI = 0, EA =1
CONTROL
INTERPRETATION
00000011
Unacknowledged Information Transfer
INTERPRETATION
ONE SECOND REPORT
G1 = 1
G2 =1
G3 =1
G4 =1
G5 =1
CRC Error Event =1
1 < CRC Error Event < 5
5 < CRC Error Event < 10
10 < CRC Error Event < 100
100 < CRC Error Event < 319
CRC Error Event > 320
G6 =1
SE=1
FE-=1
LV=1
SL=1
Severely - Errored Framing Event >=1
Frame Synchronization Bit Error Event >=1
Line code Violation Event >=1
Slip Event >=1
LB=1
U1,U2=0
R=0
Payload Loopback Activated
Under Study for sync.
Reserved - set to 0
NmNI=00,01,10,11
One Second Module 4 counter
FCS
INTERPRETATION
VARIABLE
CRC16 Frame Check Sequence
7.2.1 External Data Link
In T1 mode, MT9076 has two pairs of pins (TxDL and TxDLCLK, RxDL and RxDLCLK) dedicated to transmitting
and receiving bits in the selected overhead bit positions. Pins TxDLCLK and RxDLCLK are clock outputs available
for clocking data into the MT9076 (for transmit) or external device (for receive information). Each clock operates at
4 Khz. In the SLC-96 mode the optional serial data link is multiplexed into the Fs bit position. In the ESF mode, the
serial data link is multiplexed into odd frames, i.e., the FDL bit positions.
7.2.2 Bit - Oriented Messaging
In T1 mode, MT9076 Bit oriented messaging may be selected by setting bit 6 (BIOMEn) in the Data Link Control
Word (page 1H, address 12H). The transmit data link will contain the repeating serial data stream
111111110xxxxxx0 where the byte 0xxxxxx0 originates from the user programmed register “Transmit Bit Oriented
Message” - page 1H address 13H. The receive BIOM register “Receive Bit Oriented Message” - page 3H, address
15H, will contain the last received valid message (the 0xxxxxx0 portion of the incoming serial bit stream). To
prevent spurious inputs from creating false messages, a new message must be present in 7 of the last 10
appropriate byte positions before being loaded into the receive BIOM register. When a new message has been
received, a maskable interrupt (maskable by setting bit 1 low in Interrupt Mask Word Three - page 1H, address
1EH) may occur.
8.0 Floating HDLC Channels
MT9076 has three embedded HDLC controllers (HDLC0, HDLC1, HDLC2) each of which includes the following
features:
•
•
•
Independent transmit and receive FIFO's;
Receive FIFO maskable interrupts for nearly full (programmable interrupt levels) and overflow conditions;
Transmit FIFO maskable interrupts for nearly empty (programmable interrupt levels) and underflow
conditions;
•
Maskable interrupts for transmit end-of-packet and receive end-of-packet;
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Zarlink Semiconductor Inc.
MT9076B
Data Sheet
•
•
Maskable interrupts for receive bad-frame (includes frame abort);
Transmit end-of-packet and frame-abort functions.
Each controller may be attached to any of the active 64 Kkb/s channels (24 in the case of T1, 31 in the case of E1).
HDLC0 may also be attached to the FDL in a T1 ESF link by connecting it to phantom channel 31 when
programming the HDLC Select Word. If HDLC0 is attached to channel 0 in E1 mode, only the activated Sa bits (as
per the Multiframe and Data Selection Word) will be transmit and received by the controller.
8.1 Channel Assignment
In T1 mode, any DS1 channel can be connected to either of HDLC0,1 or 2, operating at 56 or 64 Kb/s. Setting
control bit H1R64 (address 12 H on page 01H) high selects 64 Kb/s operation for all HDLCs. Setting this bit low
selects 56 Kb/s for all HDLC. Interrupts from any of the HDLCs are masked when they are disconnected.
In E1 mode, all PCM-30 channels except channel 0 can be connected to either of HDLC0,1 or 2. HDLC1 and
HDLC2 operate at 64 Kb/s. HDLC0 operates at 64 kb/s when connected to any of channels 1 to 31. When
connected to channel 0 HDLC0 operates at 4, 8, 12, 16 or 20 Kb/s depending on the number of activated Sa bits.
HDLCs can be activated by programming the HDLC Select Words (page 02H, addresses 19H, 1AH and 1BH for
HDLC0, HDLC1 and HDLC2 respectively).
8.2 HDLC Description
The HDLC handles the bit oriented packetized data transmission as per X.25 level two protocol defined by CCITT. It
provides flag and abort sequence generation and detection, zero insertion and deletion, and Frame Check
Sequence (FCS) generation and detection. A single byte, dual byte and all call address in the received frame can
be recognized. Access to the receive FCS and inhibiting of transmit FCS for terminal adaptation are also provided.
Each HDLC controller has a 128 byte deep FIFO associated with it. The status and interrupt flags are
programmable for FIFO depths that can vary from 16 to 128 bytes in steps of 16 bytes. These and other features
are enabled through the HDLC control registers on page 0BH and 0CH.
8.2.1 HDLC Frame Structure
In T1 mode or E1 mode, a valid HDLC frame begins with an opening flag, contains at least 16 bits of address and
control or information, and ends with a 16 bit FCS followed by a closing flag. Data formatted in this manner is also
referred to as a “packet”. Refer to Table 17: HDLC Frame Format
Flag (7E)
Data Field
FCS
Flag (7E)
One Byte
01111110
n Bytes
n 2
Two Bytes
One Byte
01111110
Table 17 - HDLC Frame Format
All HDLC frames start and end with a unique flag sequence “01111110”. The transmitter generates these flags and
appends them to the packet to be transmitted. The receiver searches the incoming data stream for the flags on a
bit- by-bit basis to establish frame synchronization.
The data field consists of an address field, control field and information field. The address field consists of one or
two bytes directly following the opening flag. The control field consists of one byte directly following the address
field. The information field immediately follows the control field and consists of N bytes of data. The HDLC does not
distinguish between the control and information fields and a packet does not need to contain an information field to
be valid.
The FCS field, which precedes the closing flag, consists of two bytes. A cyclic redundancy check utilizing the
CRC-CCITT standard generator polynomial “X16+X12+X5+1” produces the 16-bit FCS. In the transmitter the FCS is
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Zarlink Semiconductor Inc.
MT9076B
Data Sheet
calculated on all bits of the address and data field. The complement of the FCS is transmitted, most significant bit
first, in the FCS field. The receiver calculates the FCS on the incoming packet address, data and FCS field and
compares the result to “F0B8”. If no transmission errors are detected and the packet between the flags is at least 32
bits in length then the address and data are entered into the receive FIFO minus the FCS which is discarded.
8.2.2 Data Transparency (Zero Insertion/Deletion)
Transparency ensures that the contents of a data packet do not imitate a flag, go-ahead, frame abort or idle
channel. The contents of a transmitted frame, between the flags, is examined on a bit-by-bit basis and a 0 bit is
inserted after all sequences of 5 contiguous 1 bits (including the last five bits of the FCS). Upon receiving five
contiguous 1s within a frame the receiver deletes the following 0 bit.
8.2.3 Invalid Frames
A frame is invalid if one of the following four conditions exists (Inserted zeros are not part of a valid count):
•
•
•
•
If the FCS pattern generated from the received data does not match the “F0B8” pattern then the last data
byte of the packet is written to the received FIFO with a ‘bad packet’ indication.
A short frame exists if there are less than 25 bits between the flags. Short frames are ignored by the receiver
and nothing is written to the receive FIFO.
Packets which are at least 25 bits in length but less than 32 bits between the flags are also invalid. In this
case the data is written to the FIFO but the last byte is tagged with a “bad packet” indication.
If a frame abort sequence is detected the packet is invalid. Some or all of the current packet will reside in the
receive FIFO, assuming the packet length before the abort sequence was at least 26 bits long.
8.2.4 Frame Abort
The transmitter will abort a current packet by substituting a zero followed by seven contiguous 1s in place of the
normal packet. The receiver will abort upon reception of seven contiguous 1s occurring between the flags of a
packet which contains at least 26 bits.
Note that should the last received byte before the frame abort end with contiguous 1s, these are included in the
seven 1s required for a receiver abort. This means that the location of the abort sequence in the receiver may occur
before the location of the abort sequence in the originally transmitted packet. If this happens then the last data
written to the receive FIFO will not correspond exactly with the last byte sent before the frame abort.
8.2.5 Interframe Time Fill and Link Channel States
When the HDLC transmitter is not sending packets it will wait in one of two states
•
Interframe Time Fill state: This is a continuous series of flags occurring between frames indicating that the
channel is active but that no data is being sent.
•
•
Idle state: An idle Channel occurs when at least 15 contiguous 1s are transmitted or received.
In both states the transmitter will exit the wait state when data is loaded into the transmitter FIFO.
8.2.6 Go-Ahead
A go ahead is defined as the pattern “011111110” (contiguous 7Fs) and is the occurrence of a frame abort sequence
followed by a zero, outside of the boundaries of a normal packet. Being able to distinguish a proper (in packet)
frame abort sequence from one occurring outside of a packet allows a higher level of signaling protocol which is not
part of the HDLC specifications.
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Zarlink Semiconductor Inc.
MT9076B
Data Sheet
8.3 HDLC Functional Description
The HDLC transceiver can be reset by either the power reset input signal or by the HRST Control bit in the test
control register (software reset). When reset, the HDLC Control Registers are cleared, resulting in the transmitter
and receiver being disabled. The Receiver and Transmitter can be enabled independent of one another through
Control Register 1. The transceiver input and output are enabled when the enable control bits in Control Register 1
are set. Transmit to receive loopback as well as a receive to transmit loopback are also supported. Transmit and
receive bit rates and enables can operate independently. In MT9076 the transceiver can operate at a continuous
rate independent of RXcen and TXcen (free run mode) by setting the Frun bit of Control Register 1.
Received packets from the serial interface are sectioned into bytes by an HDLC receiver that detects flags, checks
for go-ahead signals, removes inserted zeros, performs a cyclical redundancy check (CRC) on incoming data, and
monitors the address if required. Packet reception begins upon detection of an opening flag. The resulting bytes are
concatenated with two status bits (RQ9, RQ8) and placed in a receiver first-in-first-out (Rx FIFO); a buffer register
that generates status and interrupts for microprocessor read control.
In conjunction with the control circuitry, the microprocessor writes data bytes into a Tx buffer register (Tx FIFO) that
generates status and interrupts. Packet transmission begins when the microprocessor writes a byte to the Tx FIFO.
Two status bits are added to the Tx FIFO for transmitter control of frame aborts (FA) and end of packet (EOP) flags.
Packets have flags appended, zeros inserted, and a CRC, also referred to as frame checking sequence (FCS),
added automatically during serial transmission. When the Tx FIFO is empty and finished sending a packet,
Interframe Time Fill bytes (continuous flags (7E hex)), or Mark Idle (continuous ones) are transmitted to indicate
that the channel is idle.
8.3.1 HDLC Transmitter
Following initialization and enabling, the transmitter is in the Idle Channel state (Mark Idle), continuously sending
ones. Interframe Time Fill state (Flag Idle) is selected by setting the Mark idle bit in Control Register 1 high1. The
Transmitter remains in either of these two states until data is written to the Tx FIFO. Control Register 1 bits EOP
(end of packet) and FA (Frame Abort) are set as status bits before the microprocessor loads 8 bits of data into the
10 bit wide FIFO (8 bits data and 2 bits status). To change the tag bits being loaded in the FIFO, Control Register 1
must be written to before writing to the FIFO. However, EOP and FA are reset after writing to the TX FIFO. The
Transmit Byte Count Registers may also be used to tag an end of packet. The total packet size may be
programmed to be up to 65,535 bytes. For a packet length of 1 to 255 bytes it is only necessary to write the packet
size into the Lower Transmit Byte Count Register. For a packet length of 256 to 65,535 bytes it is necessary to write
the 16 bit binary count into the Extended Transmit Byte Count Register (MSByte) and the Lower Transmit Byte
Count Register (LSByte). Note that the order of writing the upper byte before the lower byte must be observed even
when the lower byte is all zero. Internal registers are loaded with the number of bytes in the packet and
decremented after every write to the Tx FIFO. When a count of one is reached, the next byte written to the FIFO is
tagged as an end of packet. The register may be made to cycle through the same count if the packets are of the
same length by setting Control Register 2 bit Cycle.
If the transmitter is in the Idle Channel state when data is written to the Tx FIFO, then an opening flag is sent and
data from Tx FIFO follows. Otherwise, data bytes are transmitted as soon as the current flag byte has been sent. Tx
FIFO data bytes are continuously transmitted until either the FIFO is empty or an EOP or FA status bit is read by the
transmitter. After the last bit of the EOP byte has been transmitted, a 16-bit FCS is sent followed by a closing flag.
When multiple packets of data are loaded into Tx FIFO, only one flag is sent between packets.
1. If the MT9076 HDLC transmitter is set up in the Mark-Idle state (YF2 MI is 1) then it will occasionally
(less than 1% of the time) fail to transmit the opening flag when it is changed from the disabled state to the
enabled state (YF2 TXEN changed from 0 to 1). A missing opening flag will cause the packet to be lost at
the receiving end.
This problem only affects the first packet transmitted after the HDLC transmitter is enabled. Subsequent
packets ar unaffected.
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Zarlink Semiconductor Inc.
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Data Sheet
Frame aborts (the transmission of 7F hex), are transmitted by tagging a byte previously written to the Tx FIFO.
When a byte has an FA tag, then an FA is sent instead of that tagged byte. That is, all bytes previous to but not
including that byte are sent. After a Frame Abort, the transmitter returns to the Mark Idle or Interframe Time Fill
state, depending on the state of the Mark idle control bit.
Tx FIFO underrun will occur if the FIFO empties and the last byte did not have either an EOP or FA tag. A frame
abort sequence will be sent when an underrun occurs.
The following list is an example of the transmission of a three byte packet (’AA’’03’’77’ hex) (Interframe time fill).
TXcen can be enabled before or after this sequence.
(a) Write ’04’hex to Control Register 1
(b) Write ’AA’ hex to TX FIFO
(c) Write ’03’hex to TX FIFO
(d) Write ’34’hex to Control Register 1
(e) Write ’77’hex to TX FIFO
-Mark idle bit set
-Data byte
-Data byte
-TXEN; EOP; Mark idle bits set
-Final data byte
The transmitter may be enabled independently of the receiver. This is done by setting the TXEN bit of the Control
Register. Enabling happens immediately upon writing to the register. Disabling using TXen will occur after the
completion of the transmission of the present packet; the contents of the FIFO are not cleared. Disabling will consist
of stopping the transmitter clock. The Status and Interrupt Registers may still be read and the FIFO and Control
Registers may be written to while the transmitter is disabled. The transmitted FCS may be inhibited using the Tcrci
bit of Control Register 2. In this mode the opening flag followed by the data and closing flag is sent and zero
insertion still included, but no CRC. That is, the FCS is injected by the microprocessor as part of the data field. This
is used in V.120 terminal adaptation for synchronous protocol sensitive UI frames.
8.3.2 HDLC Receiver
After initialization and enabling, the receiver clocks in serial data, continuously checking for Go-aheads (0 1111
1110), flags (0111 1110), and Idle Channel states (at least fifteen ones). When a flag is detected, the receiver
synchronizes itself to the serial stream of data bits, automatically calculating the FCS. If the data length between
flags after zero removal is less than 25 bits, then the packet is ignored so no bytes are loaded into Rx FIFO. When
the data length after zero removal is between 25 and 31 bits, a first byte and bad FCS code are loaded into the Rx
FIFO (see definition of RQ8 and RQ9 below). For an error-free packet, the result in the CRC register should match
the HEX pattern of’F0B8’ when a closing flag is detected.
If address recognition is required, the Receiver Address Recognition Registers are loaded with the desired address
and the Adrec bit in the Control Register 1 is set high. Bit 0 of the Address Registers is used as an enable bit for
that byte, thus allowing either or both of the first two bytes to be compared to the expected values. Bit 0 of the first
byte of the address received (address extension bit) will be monitored to determine if a single or dual byte address
is being received. If this bit is 0 then a two byte address is being received and then only the first six bits of the first
address byte are compared. An all call condition is also monitored for the second address byte; and if received the
first address byte is ignored (not compared with mask byte). If the address extension bit is a 1 then a single byte
address is being received. In this case, an all call condition is monitored for in the first byte as well as the mask byte
written to the comparison register and the second byte is ignored. Seven bits of address comparison can be
realized on the first byte if this is a single byte address by setting the Seven bit of Control Register 2.
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Zarlink Semiconductor Inc.
MT9076B
Data Sheet
The following two Status Register bits (RQ8 and RQ9) are appended to each data byte as it is written to the Rx
FIFO. They indicate that a good packet has been received (good FCS and no frame abort), or a bad packet with
either incorrect FCS or frame abort. The Status and Interrupt Registers should be read before reading the Rx FIFO
since status and interrupt information correspond to the byte at the output of the FIFO (i.e., the byte about to be
read). The Status Register bits are encoded as follows:
RQ9
RQ8
Byte status
1
0
1
0
1
1
0
0
last byte (bad packet)
first byte
last byte (good packet)
packet byte
The end-of-packet-detect (EOPD) interrupt indicates that the last byte written to the Rx FIFO was an EOP byte (last
byte in a packet). The end-of-packet-read (EopR) interrupt indicates that the byte about to be read from the Rx
FIFO is an EOP byte (last byte in a packet). The Status Register should be read to see if the packet is good or bad
before the byte is read.
A minimum size packet has an 8-bit address, an 8-bit control byte, and a 16-bit FCS pattern between the opening
and closing flags (see Section 9.3.2). Thus, the absence of a data transmission error and a frame length of at least
32 bits results in the receiver writing a valid packet code with the EOP byte into Rx FIFO. The last 16 bits before the
closing flag are regarded as the FCS pattern and will not be transferred to the receiver FIFO. Only data bytes
(Address, Control, Information) are loaded into the Rx FIFO.
In the case of an Rx FIFO overflow, no clocking occurs until a new opening flag is received. In other words, the
remainder of the packet is not clocked into the FIFO. Also, the top byte of the FIFO will not be written over. If the
FIFO is read before the reception of the next packet then reception of that packet will occur. If two beginning of
packet conditions (RQ9=0;RQ8=1) are seen in the FIFO, without an intermediate EOP status, then overflow
occurred for the first packet.
The receiver may be enabled independently of the transmitter. This is done by setting the RXEN bit of Control
Register 1. Enabling happens immediately upon writing to the register. Disabling using RXEN will occur after the
present packet has been completely loaded into the FIFO. Disabling can occur during a packet if no bytes have
been written to the FIFO yet. Disabling will consist of disabling the internal receive clock. The FIFO, Status, and
Interrupt Registers may still be read while the receiver is disabled. Note that the receiver requires a flag before
processing a frame, thus if the receiver is enabled in the middle of an incoming packet it will ignore that packet and
wait for the next complete one.
The receive CRC can be monitored in the Rx CRC Registers. These registers contain the actual CRC sent by the
other transmitter in its original form; that is, MSB first and bits inverted. These registers are updated by each end of
packet (closing flag) received and therefore should be read when an end of packet is received so that the next
packet does not overwrite the registers.
9.0 Slip Buffers
9.1 Slip Buffer in T1 Mode
In T1 mode, MT9076 contains two slip buffers, one on the transmit side, and one on the receive side. Both sides
may perform a controlled slip. The mechanisms that govern the slip function are a function of backplane timing and
the mapping between the ST-BUS channels and the DS1 channels. The slip mechanisms are different for the
transmit and receive slip buffers. The extracted 1.544 MHz clock (Exclk) and the internally generated transmit
1.544 MHz clock are distinct. Slips on the transmit side are independent from slips on the receive side. In IMA mode
neither the transmit nor receive slip buffer is activated.
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Zarlink Semiconductor Inc.
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Data Sheet
The transmit slip buffer has data written to it from the near end 2.048 Mb/s stream. The data is clocked out of the
buffer using signals derived from the transmit 1.544 MHz clock. The transmit 1.544 MHz clock is always phase
locked to the DSTi 2.048 Mb/s stream. If the system 4.096 MHz clock (C4b) is internally generated (pin BS/LS low),
then it is hard locked to the 1.544 MHz clock. No phase drift or wander can exist between the two signals - therefore
no slips will occur. The delay through the transmit elastic buffer is then fixed, and is a function of the relative
mapping between the DSTi channels and the DS1 timeslots. These delays vary with the position of the channel in
the frame. For example, DS1 timeslot 1 sits in the elastic buffer for approximately 1 usec and DS1 timeslot 24 sits in
the elastic buffer for approximately 32 usec.
0 uS
Write
Pointer
Read Pointer
4 uS
92 uS
Read Pointer
221 uS
Wander Tolerance
512 Bit
Elastic
Store
62 uS
188 uS
92 uS
96 uS
Read Pointer
129 uS
Read Pointer
Read Vectors
Minimum Delay
Frame 0
Frame 1
Write Vectors
Frame 0
Frame 1
Frame 1
Frame 0
Read Vectors - Maximum Delay
Figure 11 - Read and Write Pointers in the Transmit Slip Buffers
If the system 4.096 MHz clock (C4b) is externally generated (pin BS/LS high), the transmit 1.544 MHz clock is
phase locked to it, but the PLL is designed to filter jitter present in the C4b clock. As a result phase drift will result
between the two signals. The delay through the transmit elastic buffer will vary in accordance with the input clock
drift, as well as being a function of the relative mapping between the DSTi channels and the DS1 timeslots. If the
read pointers approach the write pointers (to within approximately 1 usec) or the delay through the transmit buffer
exceeds 218 usecs a controlled slip will occur. The contents of a single frame of DS1 data will be skipped or
repeated; a maskable interrupt (masked by setting bit 1 - TxSLPI high in Interrupt Mask Word Zero - page 1H,
address 1bH) will be generated, and the status bit TSLIP (page 3H, address 17H) of MSB Transmit Slip Buffer
register will toggle. The direction of the slip is indicated by bit 6 of the same register (TSLPD). The relative phase
delay between the system frame boundary and the transmit elastic frame read boundary is measured every frame
and reported in the Transmit Slip Buffer Delay register- (page 3H, address 17H). In addition the relative offset
between these frame boundaries may be programmed by writing to this register. Every write to Transmit Elastic
Buffer Set Delay Word resets the transmit elastic frame count bit TxSBMSB (address 17H, page 3H). After a write
the delay through the slip buffer is less than 1 frame in duration. Each write operation will result in a disturbance of
the transmit DS1 frame boundary, causing the far end to go out of sync. Writing BC (hex) into the TxSBDLY register
maximizes the wander tolerance before a controlled slip occurs. Under normal operation no slips should occur in
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Zarlink Semiconductor Inc.
MT9076B
Data Sheet
the transmit path. Slips will only occur if the input C4b clock has excess wander, or the Transmit Elastic Buffer Set
Delay Word register is initialized too close to the slip pointers after system initialization.
The two frame receive elastic buffer is attached between the 1.544 Mbit/s DS1 receive side and the 2.048 Mbit/s
ST-BUS side of the MT9076. Besides performing rate conversion, this elastic buffer is configured as a slip buffer
which absorbs wander and low frequency jitter in multi-trunk applications. The received DS1 data is clocked into the
slip buffer with the Exclk clock and is clocked out of the slip buffer with the system C4b clock. The Exclk extracted
clock is generated from, and is therefore phase-locked with, the receive DS1 data. In the case of Internal mode (pin
BS/LS set low) operation, the Exclk clock may be phase-locked to the C4b clock by an internal phase locked loop
(PLL). Therefore, in a single trunk system the receive data is in phase with the Exclk clock, the C4b clock is phase
locked to the E1.5o clock, and the read and write positions of the slip buffer track each other.
In a multi-trunk slave or loop-timed system (i.e., PABX application) a single trunk will be chosen as a network
synchronizer, which will function as described in the previous paragraph. The remaining trunks will use the system
timing derived from the synchronizer to clock data out of their slip buffers. Even though the DS1 signals from the
network are synchronous to each other, due to multiplexing, transmission impairments and route diversity, these
signals may jitter or wander with respect to the synchronizing trunk signal. Therefore, the Exclk clocks of
non-synchronized trunks may wander with respect to the Exclk clock of the synchronizer and the system bus.
Network standards state that, within limits, trunk interfaces must be able to receive error-free data in the presence
of jitter and wander (refer to network requirements for jitter and wander tolerance). The MT9076 will allow 92 usec
(140 UI, DS1 unit intervals) of wander and low frequency jitter before a frame slip will occur.
When the C4b and the Exclk clocks are not phase-locked, the rate at which data is being written into the slip buffer
from the DS1 side may differ from the rate at which it is being read out onto the ST-BUS. If this situation persists,
the delay limits stated in the previous paragraph will be violated and the slip buffer will perform a controlled frame
slip. That is, the buffer pointers will be automatically adjusted so that a full DS1 frame is either repeated or lost. All
frame slips occur on frame boundaries.
The minimum delay through the receive slip buffer is approximately 1 usec and the maximum delay is
approximately 249 uS. Figure 12 illustrates the relationship between the read and write pointers of the receive slip
buffer (contiguous time slot mapping). Measuring clockwise from the write pointer, if the read page pointer comes
within 8 usec of the write page pointer a frame slip will occur, which will put the read page pointer 157 usec from the
write page pointer. Conversely, if the read page pointer moves more than 249 usec from the write page pointer, a
slip will occur, which will put the read page pointer 124 usec from the write page pointer. This provides a worst case
hysteresis of 92 usec peak = 142 U.I.
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Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Write
Pointer
0 uS
Read Pointer
Read Pointer
249 uS
32 uS
92 uS
Wander Tolerance
512 Bit
Elastic
Store
62 uS
188 uS
92 uS
157 uS
124 uS
Read Pointer
Read Pointer
Read Vectors
Frame 0
XXX
Frame 1
XXX
Minimum Delay
Write Vectors
Frame 0
Frame 1
Frame 0
XXX
Frame 1
XXX
Read Vectors - Maximum Delay
Figure 12 - Read and Write Pointers in the Receive Slip Buffers
The RSLIP and RSLPD status bits (page 3H, address 13H, bits 7 and 6 respectively) give indication of a receive
slip occurrence and direction. A maskable interrupt RxSLPI (page 1H, address 1BH, bit 0 - set high to mask) is also
provided. RSLIP changes state in the event of a slip. If RSLPD=0, the slip buffer has overflowed and a frame was
lost; if RSLPD=1, a underflow condition occurred and a frame was repeated.
9.2 Slip Buffer in E1 Mode
In E1 mode, in addition to the elastic buffer in the jitter attenuator(JA), another elastic buffer (two frames deep) is
present, attached between the receive side and the ST-BUS side of the MT9076. This elastic buffer is configured as
a slip buffer which absorbs wander and low frequency jitter in multi-trunk applications. The received PCM 30 data is
clocked into the slip buffer with the Exclk clock and is clocked out of the slip buffer with the C4b clock. The Exclk
extracted clock is generated from, and is therefore phase-locked with, the receive PCM 30 data. In normal
operation, the C4b clock will be phase-locked to the Exclk clock by a phase locked loop (PLL). Therefore, in a
single trunk system the receive data is in phase with the Exclk clock, the C4b clock is phase-locked to the Exclk
clock, and the read and write positions of the slip buffer will remain fixed with respect to each other.
In a multi-trunk slave or loop-timed system (i.e., PABX application) a single trunk will be chosen as a network
synchronizer, which will function as described in the previous paragraph. The remaining trunks will use the system
timing derived from the synchronizer to clock data out of their slip buffers. Even though the PCM 30 signals from the
network are synchronous to each other, due to multiplexing, transmission impairments and route diversity, these
signals may jitter or wander with respect to the synchronizing trunk signal. Therefore, the
Exclk clocks of non-synchronizer trunks may wander with respect to the Exclk clock of the synchronizer and the
system bus.
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Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Network standards state that, within limits, trunk interfaces must be able to receive error-free data in the presence
of jitter and wander (refer to network requirements for jitter and wander tolerance). The MT9076 will allow a
maximum of 26 channels (208 UI, unit intervals) of wander and low frequency jitter before a frame slip will occur.
The minimum delay through the receive slip buffer is approximately two channels and the maximum delay is
approximately 60 channels (see Figure 13).
When the C4b and the Exclk clocks are not phase-locked, the rate at which data is being written into the slip buffer
from the PCM 30 side may differ from the rate at which it is being read out onto the ST-BUS. If this situation
persists, the delay limits stated in the previous paragraph will be violated and the slip buffer will perform a controlled
frame slip. That is, the buffer pointers will be automatically adjusted so that a full PCM 30 frame is either repeated
or lost. All frame slips occur on PCM 30 frame boundaries.
Two status bits, RSLIP and RSLPD (page03H, address13H) give indication of a slip occurrence and direction.
RSLIP changes state in the event of a slip. If RSLPD=0, the slip buffer has overflowed and a frame was lost; if
RSLPD=1, a underflow condition occurred and a frame was repeated. A maskable interrupt SLPI (page 01H,
address 1BH) is also provided.
Figure 13 illustrates the relationship between the read and write pointers of the receive slip buffer. Measuring
clockwise from the write pointer, if the read pointer comes within two channels of the write pointer a frame slip will
occur, which will put the read pointer 34 channels from the write pointer. Conversely, if the read pointer moves more
than 60 channels from the write pointer, a slip will occur, which will put the read pointer 28 channels from the write
pointer. This provides a worst case hysteresis of 13 channels peak (26 channels peak-to-peak) or a wander
tolerance of 208 UI.
Write
Pointer
Read Pointer
Read Pointer
60 CH
13 CH
2 CH
Wander Tolerance
512 Bit
Elastic
Store
15 CH
47 CH
-13 CH
34 CH
28 CH
Read Pointer
Read Pointer
Figure 13 - Read and Write Pointers in the Slip Buffers
10.0 Framing Algorithm
10.1 Frame Alignment in T1 Mode
In T1 mode, MT9076 will synchronize to DS1 lines formatted with either the D4 or ESF protocol. In either mode the
framer maintains a running 3 bit history of received data for each of the candidate bit positions. Candidate bit
positions whose incoming patterns fail to match the predicted pattern (based on the 3 bit history) are winnowed out.
If, after a 10 bit history has been examined, only one candidate bit position remains within the framing bit period, the
receive side timebase is forced to align to that bit position. If no candidates remain after a 10 bit history, the process
is re-initiated. If multiple candidates exist after a 24 bit history timeout period, the framer forces the receive side
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Zarlink Semiconductor Inc.
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Data Sheet
timebase to synchronize to the next incoming valid candidate bit position. In the event of a reframe, the framer
starts searching at the next bit position over. This prevents persistent locking to a mimic as the controller may
initiate a software controlled reframe in the event of locking to a mimic.
Under software control the framing criteria may be tuned (see Framing Mode Select Register, page 1H, address
10H). Selecting D4 framing invites a further decision whether or not to include a cross check of Fs bits along with
the Ft bits. If Fs bits are checked (by setting control bit CXC high - bit 5 of the Framing Mode Select Word, page 1H,
address 10H), multiframe alignment is forced at the same time as terminal frame alignment. If only Ft bits are
checked, multiframe alignment is forced separately, upon detection of the Fs bit history of 00111 (for normal D4
trunks) or 000111000111 (for SLC-96 trunks). For D4 trunks, a reframe on the multiframe alignment may be forced
at any time without affecting terminal frame alignment.
In ESF mode, the circuit will optionally confirm the CRC-6 bits before forcing a new frame alignment. This is
programmed by setting control bit CXC high (bit 5 of the Framing Mode Select Word, page 1H, address 10H). A
CRC-6 confirmation adds a minimum of 6 milliseconds to the reframe time. If no CRC-6 match is found after 16
attempts, the framer moves to the next valid candidate bit position (assuming other bit positions contain a match to
the framing pattern) or re-initiates the whole framing procedure (assuming no bit positions have been found to
match the framing pattern).
The framing circuit is off - line. During a reframe, the rest of the circuit operates synchronous with the last frame
alignment. Until such time as a new frame alignment is achieved, the signaling bits are frozen in their states at the
time that frame alignment was lost, and error counting for Ft, Fs, ESF framing pattern or CRC-6 bits is suspended.
10.2 Frame Alignment in E1 Mode
In E1 mode, MT9076 contains three distinct framing algorithms: basic frame alignment, signaling multiframe
alignment and CRC-4 multiframe alignment. Figure 14 is a state diagram that illustrates these algorithms and how
they interact.
After power-up, the basic frame alignment framer will search for a frame alignment signal (FAS) in the PCM 30
receive bit stream. Once the FAS is detected, the corresponding bit 2 of the non-frame alignment signal (NFAS) is
checked. If bit 2 of the NFAS is zero a new search for basic frame alignment is initiated. If bit 2 of the NFAS is one
and the next FAS is correct, the algorithm declares that basic frame synchronization has been found (i.e., page
03H, address 10H, bit 7, SYNC is zero).
Once basic frame alignment is acquired the signaling and CRC-4 multiframe searches will be initiated. The
signaling multiframe algorithm will align to the first multiframe alignment signal pattern (MFAS = 0000) it receives in
the most significant nibble of channel 16 (page 3, address 10H, bit 6, MFSYNC = 0). signaling multiframing will be
lost when two consecutive multiframes are received in error.
The CRC-4 multiframe alignment signal is a 001011 bit sequence that appears in PCM 30 bit position one of the
NFAS in frames 1, 3, 5, 7, 9 and 11 (see Table 11). In order to achieve CRC-4 synchronization two consecutive
CRC-4 multiframe alignment signals must be received without error (page 03H, address 10H CRCSYN = 0).
The E1 framing algorithm supports automatic interworking of interfaces with and without CRC-4 processing
capabilities. That is, if an interface with CRC-4 capability, achieves valid basic frame alignment, but does not
achieve CRC-4 multiframe alignment by the end of a predefined period, the distant end is considered to be a
non-CRC-4 interface. When the distant end is a non-CRC-4 interface, the near end automatically suspends receive
CRC-4 functions, continues to transmit CRC-4 data to the distant end with its E-bits set to zero, and provides a
status indication. Naturally, if the distant end initially achieves CRC-4 synchronization, CRC-4 processing will be
carried out by both ends. This feature is selected when control bit AUTC (page 01H, address 10H) is set to zero.
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Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Out of synchronization
YES
NO
Search for primary basic frame
alignment signal RAI=1, Es=0.
3 consecutive
incorrect frame
alignment
signals
YES
>914 CRC errors
in one second
NO
Verify Bit 2 of non-frame
alignment signal.
YES
NO
Verify second occurrence of
frame alignment signal.
No CRC
multiframe alignment.
8 msec. timer expired*
YES
Primary basic frame synchronization
acquired. Enable traffic RAI=0, E’s=0. Start
loss of primary basic frame alignment
checking. Notes 7 & 8.
CRC-4 multi-frame alignment
Signalling multi-frame alignment
Search for multiframe
alignment signal.
Start 400 msec timer.
Note 7.
Note 7.
YES
NO
RAI = 0
Multiframe synchronization
acquired as per G.732.
Note 7.
Start 8 msec timer.
Note 7.
Basic frame
alignment acquired
NO
YES
Find two CRC frame
alignment signals.
Note 7.
No CRC
Check for two consecutive errored
multiframe alignment signals.
multiframe
alignment.
Notes 7 & 8.
8 msec.
timer expired**
CRC multiframe
alignment
CRC-to-CRC interworking. Re-align to new basic
frame alignment. Start CRC-4 processing. E-bits set as
per G.704 and I.431. Indicate CRC synchronization
achieved.
Parallel search for new basic frame
alignment signal.
Notes 6 & 7.
Notes 7& 8.
400 msec timer expired
CRC-to-non-CRC interworking. Maintain primary
basic frame alignment. Continue to send CRC-4
data, but stop CRC processing. E-bits set to ‘0’.
Indicate CRC-to-non-CRC operation. Note 7.
*
only if CRC-4 synchronization is selected and automatic CRC-4
interworking is de-selected.
** only if automatic CRC-4 interworking is selected.
Figure 14 - Synchronization State Diagram
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Data Sheet
10.2.1 Notes for Synchronization State Diagram (Figure 14)
1) The basic frame alignment, signaling multiframe alignment, and CRC-4 multiframe alignment functions
operate in parallel and are independent.
2) The receive channel associated signaling bits and signaling multiframe alignment bit will be frozen when
multiframe alignment is lost.
3) Manual re-framing of the receive basic frame alignment and signaling multiframe alignment functions can be
performed at any time.
4) The transmit RAI bit will be one until basic frame alignment is established, then it will be zero.
5) E-bits can be optionally set to zero until the equipment interworking relationship is established. When this
has been determined one of the following will take place:
a) CRC-to-non-CRC operation - E-bits = 0,
b) CRC-to-CRC operation - E-bits as per G.704 and I.431.
6) All manual re-frames and new basic frame alignment searches start after the current frame alignment signal
position.
7) After basic frame alignment has been achieved, loss of frame alignment will occur any time three consecutive
incorrect basic frame alignment signals are received. Loss of basic frame alignment will reset the complete
framing algorithm.
8) When CRC-4 multiframing has been achieved, the primary basic frame alignment and resulting multiframe
alignment will be adjusted to the basic frame alignment determined during CRC-4 synchronization.
Therefore, the primary basic frame alignment will not be updated during the CRC-4 multiframing search, but
will be updated when the CRC-4 multiframing search is complete.
10.3 Reframe
10.3.1 E1 Mode
The MT9076 will automatically force a reframe, if three consecutive frame alignment patterns or three consecutive
non-frame alignment bits are in error.
10.3.2 T1 Mode
The MT9076 will automatically force a reframe if the framing bit error density exceeds the threshold programmed by
control bits RS1-0 (Framing Mode Select Word page 1H, address 10H). RS1 = RS0 = 0 forces a reframe for 2
errors out of a sliding window of 4 framing bits. RS1 = 0, RS0 = 1 forces a reframe with 2 errors out of 5. RS1 = 1,
RS0 = 0 forces a reframe with 2 errors out of 6. RS1 = RS0 = 1 disables the automatic reframe.
In ESF mode, all framing bits are checked. In D4 mode, either Ft bits only (if control bit 2 - FSI - of Framing Mode
Select Register is set low) or Ft and Fs bits are checked (FSI set high). If the D4 secondary yellow alarm is enabled
(control bit 1 - D4SECY of Transmit Alarm Control Word page 1H, address 11H) then the Fs bit of frame 12 is not
verified for the loss of frame circuit.
In E1 or T1 mode, receive transparent mode (selected when bit 3 page 1 address 12H is high) no reframing is
forced by the device.
The user may initiate a software reframe at any time by setting bit 1, page 1, address 10H high (ReFR). Once the
circuit has commenced reframing the signaling bits are frozen until multiframe synchronization has been achieved.
11.0 MT9076 Channel Signaling
11.1 Channel Signaling in T1 Mode
In T1 mode, when control bit RBEn (page 1H, address 14H) is low the MT9076 will insert ABCD or AB signaling bits
into bit 8 of every transmit DS0 channel every 6th frame. The AB or ABCD signaling bits from received frames 6
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Zarlink Semiconductor Inc.
MT9076B
Data Sheet
and 12 (AB) or from frames 6, 12, 18 and 24 (ABCD) will be loaded into an internal storage RAM. The transmit AB/
ABCD signaling nibbles can be passed either via the micro-ports (for channels with bit 1 set high in the Per Time
Slot Control Word - pages 7H and 8H) or through related channels of the CSTi serial links, see “ST-BUS vs. DS1 to
Channel Relationship(T1)” on page 30. The receive signaling bits are always mapped to the equivalent ST-BUS
channels on CSTo. Memory pages five and six contain the transmit AB or ABCD nibbles and pages eight and nine
the receive AB or ABCD nibbles for micro-port CAS access.
The serial control streams that contain the transmit / receive signaling information (CSTi and CSTo respectively) are
clocked at 2.048 MHz. The number of signaling bits to be transmit / received = 24 (timeslots) x 4 bits per timeslot
(ABCD) = 24 nibbles. This leaves many unused nibble positions in the 2.048 MHz CSTi / CSTo bandwidth. These
unused nibble locations are tristated. The usage of the bit stream is as follows: the signaling bits are inserted /
reported in the same CSTi / CSTo channels that correspond to the DS1 channels used in DSTi / DSTo - see Table 6,
“ST-BUS vs. DS1 to Channel Relationship(T1),” on page 30. The control bit MSN (signaling Control Word, page
01H, address 14H) allows for the ABCD bit to use the most significant nibble of CSTi / CSTo (MSN set high) or the
least significant nibble (MSN set low). Unused nibbles and timeslots are tristate. In order to facilitate multiplexing on
the CSTo control stream, an additional control bit CSToEn (signaling Control Word, page 01H, address 14H) will
tristate the whole stream when set low. This control bit is forced low with the reset pin. In the case of D4 trunks, only
AB bits are reported. The control bits SM1-0 allow the user to program the 2 unused bits reported on CSTo in the
signaling nibble otherwise occupied by CD signaling bits in ESF trunks.
A receive signaling bit debounce of 6 msec. can be selected (DBEn set high - signaling Control Word, page 01H,
address 14H). It should be noted that there may be as much as 3 msec. added to this duration because signaling
equipment state changes are not synchronous with the D4 or ESF multiframe.
If multi - frame synchronization is lost (page 3H, address 10H, bit 6 MFSYNC = 1) all receive signaling bits are
frozen. They will become unfrozen when multi - frame synchronization is acquired (this is the same as terminal
frame synchronization for ESF links).
When the SIGI interrupt is unmasked, IRQ will become active when a signaling state change is detected in any of
the 24 receive channels. The SIGI interrupt mask is located on page 1, address 1EH, bit 0 (set high to enable
interrupt); and the SIGI interrupt vector is located on page 4, address 1EH.
11.2 Channel Signaling in E1 Mode
In E1 mode, when control bit TxCCS is set to one, the MT9076 is in Common Channel signaling (CCS) mode.
When TxCCS is low it is in Channel Associated signaling mode (CAS). The CAS mode ABCD signaling nibbles can
be passed either via the micro-ports (when RPSIG = 1) or through related channels of the CSTo and CSTi serial
links (when RPSIG = 0). Memory pages 09H and 0AH contain the receive ABCD nibbles and pages 05H and 06H
the transmit ABCD nibbles for micro-port CAS access.
In CAS operation, an ABCD signaling bit debounce of 14 msec. can be selected by writing a one to DBNCE control
bit. This is consistent with the signaling recognition time of ITU-T Q.422. It should be noted that there may be as
much as 2 msec. added to this duration because signaling equipment state changes are not synchronous with the
PCM 30 multiframe.
If multiframe synchronization is lost (page 03H, address 10H, when MFSYNC = 1) all receive CAS signaling nibbles
are frozen. Receive CAS nibbles will become unfrozen when multiframe synchronization is acquired.
When the CAS signaling interrupt is unmasked (page 01H, address 1EH, SIGIM=1), pin IRQ (pin 12 in PLCC, 65 in
LQFP) will become active when a signaling nibble state change is detected in any of the 30 receive channels.
In CCS mode, the data transmitted on channel 16 is sourced from channel 16 data on DSTi.
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Data Sheet
12.0 Loopbacks
In order to meet PRI Layer 1 requirements and to assist in circuit fault sectioning, the MT9076 has six loopback
functions. These are as follows:
a) Digital loopback (DSTi to DSTo at the framer/LIU interface). Bit DLBK = 0 normal; DLBK = 1 activate.
MT9076
DSTi
System
DSTo
Tx
Line
b) Remote loopback (RTIP and RRING to TTIP and TRING respectively at the Line side). Bit RLBK = 0 normal;
RLBK = 1 activate.
MT9076
Tx
Line
Rx
System
DSTo
c) ST-BUS loopback (DSTi to DSTo at the system side). Bit SLBK = 0 normal; SLBK = 1 activate.
MT9076
Tx
Line
DSTi
System
DSTo
d) Payload loopback (RTIP and RRING to TTIP and TRING respectively at the system side). Bit PLBK = 0
normal; PLBK = 1 activate. The payload loopback is effectively a physical connection of DSTo to DSTi within
the MT9076. Sbit information and the DL originate at the point of loopback.
MT9076
DSTi
System
DSTo
Tx
Rx
Line
e) Metallic Loopback. MLBK = 0 normal; MLBK = 1 activate, will isolate the external signals RTIP and RRING
from the receiver and internally connect the analog output TTIP and TRING to the receiver analog input.
MT9076
DSTi
System
DSTo
Tx
Rx
Line
f) Per time slot local and remote loopback. Remote time slot loopback control bit RTSL = 0 normal; RTSL = 1
activate, will loop around transmit ST-BUS time slots to the DSTo stream. Local time slot loopback bits LTSL
= 0 normal; LTSL = 1 activate, will loop around receive PCM 30 time slots towards the remote PCM 30 end.
MT9076
Tx
Line
Rx
DSTi
System
DSTo
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Zarlink Semiconductor Inc.
MT9076B
Data Sheet
The digital, remote, ST-BUS, payload and metallic loopbacks are located on page 1, address 15H - Coding and
Loopback Control Word. The remote and local time slot loopbacks are controlled through control bits 5 and 4 of the
Per Time Slot Control Words, pages 7H and 8H.
13.0 Performance Monitoring
13.1 Error Counters
In T1 mode, MT9076 has eight error counters, which can be used for maintenance testing and ongoing
measurement of the quality of a DS1 link and to assist the designer in meeting specifications such as TR62411 and
T1.403. All counters can be preset or cleared by writing to the appropriate locations.
Associated with each counter is a maskable event occurrence interrupt and a maskable counter overflow interrupt.
Overflow interrupts are useful when cumulative error counts are being recorded. For example, every time the
framing bit error counter overflow interrupt (FERO) occurs, 256 frame errors have been received since the last
FERO (page 04H, address 1DH)interrupt. All counters are cleared and held low by programming the counter clear
bit -CNTCLR - high (bit 4 of the Reset Control Word, page 1H, address 1AH). An alternative approach to event
reporting is to mask error events and to enable the 1 second sample bit (SAMPLE - bit 3 of the Reset Control
Word). When this bit is set the counters for change of frame alignment, loss of frame alignment, line code violation
errors, crc errors, errored framing bits, and multiframes out of sync are updated on one second intervals coincident
with the maskable one second interrupt timer.
In E1 mode, MT9076 has six error counters, which can be used for maintenance testing, and ongoing
measurement of the quality of a PCM 30 link and to assist the designer in meeting specifications such as ITU-T
I.431 and G.821. All counters can be preset or cleared by writing to the appropriate locations.
Associated with each counter is a maskable event occurrence interrupt and a maskable counter overflow interrupt.
Overflow interrupts are useful when cumulative error counts are being recorded. For example, every time the frame
error counter overflow (FERO) interrupt occurs, 256 frame errors have been received since the last FERO interrupt.
All counters are cleared and held low by programming the counter clear bit (master control page 01H, address 1A,
bit 4) high. Counter overflows set bits in the counter overflow latch (page 04H, address 1FH); this latch is cleared
when read.
The overflow reporting latch (page 04H, address 1FH) contains a register whose bits are set when individual
counters overflow. These bits stay high until the register is read.
13.2 T1 Counters
13.2.1 Framing Bit Error Counter (FC7-0)
This eight bit counter counts errors in the framing pattern. In ESF mode, any error in the 001011 framing pattern
increments the counter. In SLC-96 mode any error in the Ft bit position is counted. In D4 mode Ft errors are always
counted, Fs bits (except for the Sbit in frame 12) may optionally be counted (if control bit FSI is set high - page 1H,
address 10H, bit 2). The counter is located on page 4H, address 13H.
There are two maskable interrupts associated with the Framing bit error measurement. A single error may generate
an interrupt (enable by setting FERI high - bit 7 of the Interrupt Mask Word One, page 1H, address 1CH). A counter
overflow interrupt may be enabled by setting control bit FEOM high - bit 2 of Interrupt Mask Word Two (page 1H,
address 1DH).
13.2.2 Out Of Frame/Change Of Frame Alignment Counter (OOF3-0/COFA3-0)
This register space is shared by two nibbles. One is the count of out of frame events. The other independent
counter is incremented when, after a resynchronization, the frame alignment has moved. This count is reported in
page 4, address 13H.
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Data Sheet
There are two interrupts associated with the Change of Frame Alignment counter. A single error may generate an
interrupt (enable by setting COFAI high - bit 4 of the Interrupt Mask Word One, page 1H, address 1CH). A counter
overflow interrupt may be enabled by setting control bit COFAO high - bit 4 of Interrupt Mask Word Two (page 1H,
address 1DH).
There is one interrupt associated with the Out of Frame counter. A counter overflow interrupt may be enabled by
setting control bit OOFO high - bit 5 of Interrupt Mask Word Two (page 1H, address 1DH).
13.2.3 Multiframes out of Sync Counter (MFOOF7-MFOOF0)
This eight bit counter MFOOF7 - MFOOF0 is located on page 4 address 15H, and is incremented once per
multiframe (1.5 ms for D4 and 3 ms for ESF) during the time that the framer is out of terminal frame
synchronization.
There is a maskable interrupt associated with the measurement. A counter overflow interrupt may be enabled by
setting control bit MFOOFO high - bit 1 of Interrupt Mask Word Two (page 1H, address 1DH).
13.2.4 CRC-6 Error Counter (CC15-0)
CRC-6 errors are recorded by this counter for ESF links. This 16 bit counter is located on page 4, addresses 18H
and 19H.
There are two maskable interrupts associated with the CRC error measurement. A single error may generate an
interrupt (enable by setting CRCI high - bit 6 of the Interrupt Mask Word One, page 1H, address 1CH). A counter
overflow interrupt may be enabled by setting control bit CRCO high - bit 6 of Interrupt Mask Word Two (page 1H,
address 1DH).
13.2.5 Line Code Violation Error Counter (LCV15-LCV0)
If the control bit EXZ (page 1 address 12H bit 5) is set low, the line code violation error counter will count bipolar
violations that are not part of B8ZS encoding. If the control bit EXZ (page 1 address 12H bit 5) is set high, the line
code violation error counter will count both bipolar violations that are not part of B8ZS encoding and each
occurrence of excess zeros (more than 7 successive zeros in a received B8ZS encoded data stream and more than
15 successive zeros in a non-B8ZS encoded stream). This counter LCV15-LCV0 is 16 bits long (page 4H,
addresses 16H and 17H) and is incremented once for every line code violation received. It should be noted that
when presetting or clearing the LCV error counter, the least significant LCV counter address should be written to
before the most significant location. This counter will suspend operation when terminal frame synchronization is lost
if the control bit OOFP is set (bit 2, address 1AH - Reset Control Word).
There are two maskable interrupts associated with the line code violation error measurement. A single error may
generate an interrupt (enable by setting LCVI high - bit 3 of the Interrupt Mask Word One, page 1H, address 1CH).
A counter overflow interrupt may be enabled by setting control bit LCVO high - bit 3 of Interrupt Mask Word Two
(page 1H, address 1DH).
13.2.6 PRBS Error Counter (PS7-0)
There are two 8 bit counters associated with PRBS comparison; one for errors and one for time. Any errors that are
detected in the receive PRBS will increment the PRBS Error Rate Counter of page 04H, address 10H. Writes to this
counter will clear an 8 bit counter, PSM7-0 (page 01H, address 11H) which counts receive CRC multiframes. A
maskable PRBS counter overflow (PRBSO) interrupt (page 1, address 1DH) is associated with this counter.
13.2.7 CRC Multiframe Counter for PRBS (PSM7-0)
This eight bit counter counts receive CRC multiframes. It can be directly loaded via the microport. The counter will
also be automatically cleared in the event that the PRBS error counter is written to by the microport. This counter is
located on page 04H, address 11H.
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Data Sheet
13.3 E1 Counters
13.4 Errored FAS Counter (EFAS7-EFAS0)
An eight bit Frame Alignment Signal Error counter EFAS7 - EFAS0 is located on page 04H address 13H, and is
incremented once for every receive frame alignment signal that contains one or more errors.
There are two maskable interrupts associated with the frame alignment signal error measurement. FERI (page
01H, address 1CH) is initiated when the least significant bit of the errored frame alignment signal counter toggles,
and FERRO (page 01H, address 1DH) is initiated when the counter changes from FFH to 00H.
13.5 E-bit Counter (EC15-0)
E-bit errors are counted by the MT9076 in order to support compliance with ITU-T requirements. This sixteen bit
counter is located on page 04H, addresses 14H and 15H respectively. It is incremented by single error events, with
a maximum rate of twice per CRC-4 multiframe.
There are two maskable interrupts associated with the E-bit error measurement. EBI (page 1, address 1CH) is
initiated when the least significant bit of the counter toggles, and FEBEO (page 01H, address 1DH) is initiated when
the counter overflows.
13.6 Line Code Violation Error Counter (LCV15-LCV0)
If the control bit EXZ (page 1 address 12H bit 5) is set low, the line code violation error counter will count bipolar
violations that are not part of HDB3 encoding. If the control bit EXZ (page 1 address 12H bit 5) is set high, the line
code violation error counter will count both bipolar violations that are not part of HDB3 encoding and each
occurrence of excess zeros (more than 3 successive zeros in a received HDB3 encoded data stream and more
than 15 successive zeros in a non-HDB3 encoded stream). This counter LCV15-LCV0 is 16 bits long (page 4H,
addresses 16H and 17H) and is incremented once for every line code violation received. It should be noted that
when presetting or clearing the LCV error counter, the least significant LCV counter address should be written to
before the most significant location. This counter will suspend operation when terminal frame synchronization is lost
if the control bit OOFP is set (bit 2, address 1AH - Reset Control Word).
In E1 mode, there are two maskable interrupts associated with the line code violation error measurement. LCVI
(page 01H, address 1CH) is initiated when the l significant bit of the LCV error counter toggles. LCVO (page 01H,
address 1DH) is initiated when the counter changes from FFFFH to 0000H.
13.7 CRC-4 Error Counter (CC15-0)
CRC-4 errors are counted by the MT9076 in order to support compliance with ITU-T requirements. This sixteen bit
counter is located on page 04H, addresses 18H and 19H in E1 mode. It is incremented by single error events,
which is a maximum rate of twice per CRC-4 multiframe.
There is a maskable interrupt associated with the CRC error measurement. CRCIM (page 01H, address 1CH) is
initiated when the least significant bit of the counter toggles, and CRCOM (page 01H, address 1DH) is initiated
when the counter overflows.
13.8 PRBS Error Counter (PS7-0)
There are two 8 bit counters associated with PRBS comparison; one for errors and one for time. Any errors that are
detected in the receive PRBS will increment the PRBS Error Rate Counter of page 04H, address 10H. Writes to this
counter will clear an 8 bit counter, PSM7-0 (page 01H, address 11H) which counts receive CRC multiframes. A
maskable PRBS counter overflow (PRBSO) interrupt (page 1, address 1DH) is associated with this counter.
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Data Sheet
13.9 CRC Multiframe Counter for PRBS (PSM7-0)
This eight bit counter counts receive CRC-4 multiframes. It can be directly loaded via the microport. The counter will
also be automatically cleared in the event that the PRBS error counter is written to by the microport. This counter is
located on page 04H, address 11H.
14.0 Error Insertion
In T1 mode, six types of error conditions can be inserted into the transmit DS1 data stream through control bits,
which are located on page 1, address 19H - Error Insertion Word. These error events include the bipolar violation
errors (BPVE), CRC-6 errors (CRCE), Ft errors (FTE), Fs errors (FSE), payload (PERR) and a loss of signal
condition (LOSE). The LOSE function overrides the B8ZS encoding function.
In E1 mode, six types of error conditions can be inserted into the transmit PCM 30 data stream through control bits,
which are located on page 01H, address 19H. These error events include the bipolar violation errors (BPVE),
CRC-4 errors (CRCE), FAS errors (FASE), NFAS errors (NFSE), payload (PERR) and a loss of signal error (LOSE).
The LOSE function overrides the HDB3 encoding function.
15.0 Per Time Slot Control Words
There are two per time slot control pages (addresses AH and BH) (T1/E1) occupying a total of 24 unique addresses
in T1 mode or a total of 32 unique addresses in E1 mode. Each address controls a matching timeslot on the 24 DS1
channels (T1) or 32 PCM-30 channels (E1) and the equivalent channel data on the receive (DSTo) data. For
example address 0 of the first per time slot control page contains program control for transmit timeslot 0 and DSTo
channel 0.
Per Time Slot Control Word
Bit 7
Bit 0
T1 Mode
TXMSG PCI
RTSL
RTSL
LTSL
LTSL
TTST RRST RPSIG CC
E1 Mode
TXMSG ADI
TTST RRST RPSIG - - -
15.1 Clear Channel Capability
In T1 mode, when bit zero (CC) in the per time slot control word is set no bit robbing for the purpose of signaling will
occur in this channel. This bit is not used in E1 mode.
15.2 Microport Signaling
When bit one (RPSIG) is set, the transmit signaling for the addressed channel can only be programmed by writing
to the transmit signaling page (pages 5H and 6H) via the microport. If zero, the transmit signaling information is
constantly updated with the information from the equivalent channel on CSTi.
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Data Sheet
15.3 Per Time Slot Looping
Any channel or combination of channels may be looped from transmit (sourced from DSTi) to receive (output on
DSTo) STBUS channels. When bit four (LTSL) in the Per Time Slot Control Word is set the data from the equivalent
transmit timeslot is looped back onto the equivalent receive channel.
Any channel or combination of channels may be looped from receive (sourced from the line data) to transmit
(output onto the line) channels. When bit five (RTSL) in the Per Time Slot Control Word is set the data from the
equivalent receive timeslot is looped back onto the equivalent transmit channel.
Remote Timeslot Loopback and Local Timeslot should not be simultaneously activated in the same timeslot.
15.4 PRBS Testing
If the control bit ADSEQ is zero (from master control page 1 - access control word), any channel or combination of
transmit channels may be programmed to contain a generated pseudo random bit sequence (215 -1). The channels
are selected by setting bit three (TTST), in the per time slot control word.
If the control bit ADSEQ is zero, any combination of receive channels may be connected to the PRBS decoder
(215-1). Each error in the incoming sequence causes the PRBS error counter to increment. The receive channels
are selected by setting bit 2 (RRST) in the per time slot control word.
If PRBS is performed during a metallic or external looparound, per time slot control words with TTST set should
have RRST set as well.
15.5 Digital Milliwatt
If the control bit ADSEQ is one, a digital milliwatt sequence (Table 18) in T1 mode or (Table 19) in E1 mode may be
transmitted on any combination of selected channels. The channels are selected by setting bit three (TTST), in the
Per Time Slot Control Word.
Under the same control condition (ADSEQ equal to one), the same digital milliwatt sequence is available to replace
received data on any combination of DSTo channels. This is accomplished by setting bit two (RRST) in the Per
Time Slot Control Word for the corresponding channel.
Bit 1
Bit 2
Bit 3
Bit 4
Bit 5
Bit 6
Bit 7
Bit 8
0
0
0
0
1
1
1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
1
1
0
0
1
1
1
1
1
1
1
1
1
1
0
0
1
1
0
0
1
1
1
1
1
1
1
1
1
0
1
1
0
0
1
1
0
Table 18 - Digital Milliwatt Pattern (T1)
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Data Sheet
Bit 1
Bit 2
Bit 3
Bit 4
Bit 5
Bit 6
Bit 7
Bit 8
0
0
0
0
1
1
1
1
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
1
0
0
1
1
0
1
1
0
0
0
0
0
0
0
0
1
0
0
1
1
0
0
1
0
0
0
0
0
0
0
0
0
1
1
0
0
1
1
0
Table 19 - A-Law Digital Milliwatt Pattern (E1)
15.6 Per Channel Inversion
When bit six (PCI) in the Per Time Slot Control Word is set both transmit and receive data for the selected channel
is inverted before going onto the line / DSTo respectively.
15.7 Transmit Message
When bit seven (TXMSG) in the Per Time Slot Control Word is set the data transmit in the selected channel is
sourced from the transmit message word in Master Control page 1.
16.0 Alarms
The following alarms are detected by the receiver in T1 mode. Each may generate a maskable interrupt:
•
•
D4 Yellow Alarm - in D4 mode there are two possible yellow alarm signals. If control bit D4SECY is set low,
(page 1H, address 11H, bit 1) the criteria for a yellow alarm is an excess of’0’s (more than 285) in bit position
2 of incoming DS0 channels during an integration period of 1.5 milliseconds. It is cleared after more than
3’1’s are detected in bit position 2 of normal data in a 1.5 millisecond integration period. If D4SECY is set
high the secondary yellow alarm is selected. The detection criteria becomes 2 consecutive’1’s in the Sbit
position of the 12th frame.
ESF Yellow Alarm - In ESF mode, there are two possible yellow alarm signals. If control bit JYEL (page 1H,
address 14H, bit 0) is set low the criteria for a yellow alarm is a pattern 00000000 11111111 in seven or more
code words out of ten, If JYEL is set high, the criteria for a yellow alarm is a pattern 11111111 11111111 in
seven or more code words out of ten.
•
•
All Ones - This bit (page 3H, address 11H, bit 3) is set if less than six zeros are received on the incoming line
data during a 3 ms interval
Loss of Signal - a loss of signal condition occurs when the receive signal level is lower than 20 dB or 40 dB
below the nominal signal level for at least a millisecond or when 32 or 192 (control bit L32Z (page 01H,
address 19H, bit 1) consecutive zeros have been received. A loss of signal condition will terminate when an
average ones density of at least 12.5% has been received over a period of 193 contiguous pulse positions
starting with a pulse. The loss of signal is reported in the Receive Signal Status Word - (page 3, address 16H
bit 4).
The following alarms are detected by the receiver in E1 mode. Each may generate a maskable interrupt:
•
•
Remote Alarm Indication (RAI) - bit 3 (A) of the receive NFAS;
Alarm Indication Signal (AIS) - unframed all ones signal for at least a double frame (512 bits) or two double
frames (1024 bits);
•
Channel 16 Alarm Indication Signal - all ones signal in channel 16;
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Data Sheet
•
•
Auxiliary pattern - 101010... pattern for at least 512 bits;
Loss of Signal - a loss of signal condition occurs when the receive signal level is lower than 20 dB or 40 dB
(by setting the bit ELOS on page 02H, address 10H, bit 3) below the nominal signal level for more than a
millisecond or when more than 32 or 192 (control bit L32Z (page 01H, address 19H 9 bit 1) zeros have been
received in a row. A loss of signal condition will terminate when an average ones density of at least 12.5%
has been received over a period of 192 contiguous pulse positions starting with a pulse.
•
Remote signaling Multiframe Alarm - (Y-bit) of the multiframe alignment signal.
The alarm reporting latch (page 04H, address 12H) contains a register whose bits are set high for selected alarms.
These bits stay high until the register is read. This allows the controller to record intermittent or sporadic alarm
occurrences.
16.1 Automatic Alarms
In E1 mode, the transmission of RAI and signaling multiframe alarms can be made to function automatically from
control bits ARAI and AUTY (page 01H, address 10H). When ARAI = 0 and basic frame synchronization is lost
(SYNC = 1), the MT9076 will automatically transmit the RAI alarm signal to the far end of the link. The transmission
of this alarm signal will cease when basic frame alignment is acquired.
When AUTY = 0 and signaling multiframe alignment is not acquired (MFSYNC = 1), the MT9076 will automatically
transmit the multiframe alarm (Y-bit) signal to the far end of the link. This transmission will cease when signaling
multiframe alignment is acquired.
17.0 Detected Events
17.1 T1 Mode
17.1.1 Severely Errored Frame Event
In T1 mode, bit 5 page 3H address 10H toggles whenever a sliding window detects 2 framing errors events (Ft or
ESF) in a sliding window of 6.
17.1.2 Loop Code Detect
T1.403 defines SF mode line loopback activate and deactivate codes. These codes are either a framed or
un-framed repeating bit sequence of 00001 for activation or 001 for deactivation. The standard goes on to say that
these codes will persist for five seconds or more before the loopback action is taken. In T1 mode MT9076 will
detect both framed and unframed line activate and de-activate codes even in the presence of a BER of 3 x 10-3.
Line Loopback Disable Detect - LLDD - in the Alarm Status Word (bit 0 address 11H of page 3H) will be asserted
when a repeating 001 pattern (either framed or unframed) has persisted for 48 milliseconds. Line Loopback Enable
Detect LLED in the Alarm Status Word will be asserted when a repeating 00001 pattern (either framed or unframed)
has persisted for 48 milliseconds.
17.1.3 Pulse Density Violation Detect
In T1 mode, bit 2 of address 11H on page 3H (PDV) toggles if the receive data fails to meet ones density
requirements. It will toggle upon detection of 16 consecutive zeros on the line data, or if there are less than N ones
in a window of 8(N+1) bits - where N = 1 to 23.
17.1.4 Timer Outputs
In T1 mode, MT9076 has a one second timer derived from the 20 MHz oscillator pins. The timer may be used to
trigger interrupts for T1.403/408 performance messaging.
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Data Sheet
17.2 E1 mode
17.2.1 Consecutive Frame Alignment Patterns (CONFAP)
Two consecutive frame alignment signals in error.
17.2.2 Receive Frame Alignment Signals
These bits are received on the PCM 30 and link in bit positions two to eight of time slot 0 - frame alignment signal.
These signals form the frame alignment signal and should be 0011011.
17.2.3 Receive Non Frame Alignment Signal
This signal is received on the PCM 30 and link in bit position two of time slot 0 - non frame alignment signal.
17.2.4 Receive Multiframe Alignment Signals
These signal are received on the PCM 30 and link in bit position one to four of time slot 16 of frame zero of every
signaling multiframe.
18.0 Interrupts
The MT9076 has an extensive suite of maskable interrupts, which are divided into four categories based on the
type of event that caused the interrupt. Each interrupt has an associated mask and interrupt bit. When an
unmasked interrupt event occurs, IRQ will go low and one or more bits of the appropriate interrupt register will go
high(T1/E1). After each interrupt register is read it is automatically cleared. When all interrupt registers are cleared
IRQ will return to a high impedance state. This function can also be accomplished by toggling the INTA bit (page
01H, address 1AH, bit 5).
All the interrupts of the MT9076 in T1 and E1 mode are maskable. This is accomplished through interrupt mask
words zero to three, which are located on page 1, addresses 1BH to 1EH and the (optional) HDLC interrupt mask
located at address 16 of page B.
After a MT9076 reset (RESET pin or RST control bit), all interrupts are masked.
All interrupts may be suspended, without changing the interrupt mask words, by making the SPND control bit of
page 1, address 1AH high.
All interrupts are cleared by forcing the pin TxAO low
18.1 Interrupts on T1 Mode
Interrupt Word Zero (Page 4, Address 1BH)
Bit 7
Bit 0
TFSYNI MFSYNI TSAI
AISI
LOSI
SEI
TxSLPI RxSLPI
Interrupt Mask Word Zero (Page 1, Address 11BH)
Bit 7
Bit 0
TFSYNIM
MFSYNIM BIOMTIM AISIM LOSIM SEFIM TxSLPIM RxSLPIM
Interrupt Word One (Page 4, Address 1CH)
Bit 7
Bit 0
FEI
CRCI
YELI
COFAI
LCVI
PRBSI
PDVI
- - -
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Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Interrupt Mask Word One (Page 1, Address 1CH)
Bit 7
Bit 0
FEIM
CRCIM
YELIM
COFAIM
LCVIM
PRBSIM
PDVIM
---
Interrupt Word Two (Page 4, Address 1DH)
Bit 7
Bit 0
FEO CRCO OOFO COFAO LCVO PRBSO
MFOOFO
- - -
Interrupt Mask Word Two (Page 1, Address 1DH)
Bit 7
Bit 0
FEOM CRCOM OOFOM COFAOM LCVOM PRBSOM PRBSMFOM MFOOFOM
Interrupt Word Three (Page 4, Address 1EH)
Bit 7
Bit 0
HDLC0I
HDLC1I
HDLC2I LCDI 1SECI 5SECI BIOMI SIGI
Interrupt Mask Word Three (Page 1, Address 1EH)
Bit 7
Bit 0
HDLC0IM
HDLC1IM
HDLC2IM LCDIM LSECIM 5SECIM BIOMIM SIGIM
HDLC Interrupt Status Register (Page B,C, & D, Address
17H)
Bit 7
Bit 0
GA RxEOP
TxEOP RxFE TxFL FATxUNDER
RxFF RxOVF
HDLC Interrupt Mask Register (Page B, C, and D Address 16H)
Bit 7
Bit 0
GAIM RxEOPIM TxEOPIM RxFEIM TxFLIM FA:TxUNDERIM RxFFIM RxOVFIM
18.2 Interrupts on E1 Mode
Interrupt Word Zero (Page 4, Address 1BH)
Interrupt Mask Word Zero (Page 1, Address 1BH)
Bit 7
Bit 0 Bit 7
Bit 0
TFSYNI MFSYNI CRCSYNI AISI LOSI CEFI Y1 RxSLPI SYNIM
MFSYM
CSYNIM
AISIM
LOSIM
CEFIM
YIM
SLPIM
Interrupt Word One (Page 4, Address 1CH)
Bit 7
Interrupt Mask Word One (Page 1, Address 1CH)
Bit 0 Bit 7
Bit 0
FERRI CRCERRI EBITI AIS16I LCVI PRBSERRI AUXPI RAII
FERIM
CRCIM
EMIM AISI6IM
LCVIM
PRBSIM
AUXPIM
RAIIM
Interrupt Word Two (Page 4, Address 1DH)
Interrupt Mask Word Two (Page 1, Address 1DH)
Bit 0 Bit 7
Bit 7
Bit 0
FERRO CRCO --- FEBFO LCVO PRBSO PRBSMFO SaI
FEOM
CRCOIM
--- EBOIM LCVCOM
PRBSOM
PRBSMFOM
SaIM
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Zarlink Semiconductor Inc.
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Data Sheet
Interrupt Word Three (Page 4, Address 1EH)
Interrupt Mask Word Three (Page 1, Address 1EH)
Bit 7
Bit 0 Bit 7
Bit 0
HDLC0I HDLC1I HDLC2I JAI 1SECI 5SECI RCRI SIGI
HDLC0IM
HDLC1IM HDLC2IM
LCDIM LSECIM 5SECIM BIOMIM SIGIM
HDLC Interrupt Mask Register (Page B, C, & D, Address 16H)
HDLC Interrupt Status Register (Page B, C & D,
Address 17H)
Bit 7
Bit 0 Bit 7
Bit 0
GA RxEOP TxEOP RxFE TxFL FA:TxUNDER RxFF Rx6VF GAIM RxEOPIM TxEOPIM RxFEIM TxFLIM FA:TxUNDERIM RXFFIM RxOVFIM
19.0 Digital Framer Mode
19.1 T1 Mode
Setting bit 4 in the Configuration Control Word (address 10H of Master Control Page 2) disables the LIU and
converts the MT9076 into a digital T1 transceiver. The digital 2.048 Mb/s ST-BUS backplane maps into transmit and
receive digital 1.544 Mb/s streams. The 1.544 Mb/s transmit streams may be formatted for single phase NRZ (by
setting bit 7 of the LIU Control Word - Master Page 1 high) or two phase NRZ. The data rate conversion (between
2.048 Mb/s and 1.544 Mb/s) is done within the MT9076. The transmit 1.544 MHz clock is internally generated from
a PLL that locks onto the input C4b clock. This clock is then output on pin E1.5o/Exclk (PLCC pin 44 - LQFP pin
22). The digital 1.544 Mb/s transmit data is output on pins TXA and TXB (PLCC pins 37,38 - LQFP pins 12, 13) with
the rising edge of pin Exclk. If the control bit Tx8KEN is set high (page 2H address 10H bit 2) the pin RxMF/TxFP
will generate an 8 KHz positive frame pulse synchronous with the Sbit clocked out on TXA/TXB. Receive digital
data is clocked in on pins RRING and RTIP. This data is clocked in with the rising edge of the input 1.544 MHz clock
S/FR/Exclki (PLCC pin 66, LQFP pin 48).
19.2 E1 mode
Setting bit 4 in the Configuration Control Word (address 10H of Master Control Page 2) disables the LIU and
converts the MT9076 into a digital E1 transceiver. The digital 2.048 Mb/s ST-BUS backplane maps into transmit and
receive digital 2.048 Mb/s streams. The 2.048 Mb/s transmit data streams may be formatted for single phase NRZ
(by setting bit 7 of the LIU Control Word - Master Page 1 high) or two phase NRZ. The transmit 2.048 MHz clock is
derived from the input C4b clock. This clock is then output on pin Exclk (PLCC pin 44 - LQFP pin 22). The digital
2.048 Mb/s transmit data is output on pins TXA and TXB (PLCC pins 37,38 - LQFP pins 12, 13) with the rising edge
of Exclk. If the control bit Tx8KEN is set high (page 2H address 10H bit 2) the pin RxMF/TxFP will generate an
8 KHz positive frame pulse synchronous with the Sbit clocked out on TXA/TXB. Receive digital data is clocked in on
pins RRING and RTIP. This data is clocked in with the rising edge of the input 2.048 MHz clock S/FR/Exclki (PLCC
pin 66, LQFP pin 48).
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Zarlink Semiconductor Inc.
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Data Sheet
20.0 Control and Status Registers
20.1 T1 Mode
20.1.1 Master Control 1 (Page 01H) (T1)
Address
Register
Function
(A4A3A2A1A0)
10H (Table 21)
11H (Table 22)
12H (Table 23)
Framing Mode Select
ESF, SCL96, CXC, RS1-0, FSI, ReFR,
MFReFR
Transmit Alarm Control Word
Data Link Control Word
ESFYEL, TXSECY, D4YEL, TxAO, LUA, LDA,
D4SECY, SO
EDL, BIOMEn, EXZ, TxPDVS, TxSYNC, TRSP,
JTS, H1R64
13H (Table 24)
14H (Table 25)
Transmit Bit Oriented Message
Signaling Control Word
BIOMTx7-0
DSToEn, CSToEn, RBEn, DBEn, MSN, SM1-0,
JYEL
15H (Table 26)
Coding and Loopback Control Word
RxB8ZS, MLBK,TxB8ZS,FBS, DLBK, RLBK,
SLBK, PLBK
16H
Reserved
Set all bits to zero for normal operation
17H (Table 27)
18H (Table 28)
19H (Table 29)
Transmit Elastic buffer Set Delay Word
Transmit Message Word
Error Insertion Word
TxTSD7-0
TXM7-0
BPVE, CRCE, FTE, FSE, LOSE, PERR, L32Z,
LOS/LOF
1AH (Table 30)
1BH (Table 31)
1CH (Table 32)
1DH (Table 33)
1EH (Table 34)
1FH (Table 35)
Reset Control Word
RST, SPND, INTA, CNTCLR, SAMPLE, OOFP,
D20
Interrupt Mask Word Zero
Interrupt Mask Word One
Interrupt Mask Word Two
Interrupt Mask Word Three
LIU Receiver Word
TFSYNIM, MFSYNIM, BIOMTIM, AISIM,
LOSIM, SEFIM, TxSLPIM, RxSLPIM
FEIM, CRCIM, YELIM, LCVIM, COFAIM,
PRBSIM, PDVIM
FEOM, CRCOM, OOFOM, COFAOM, LCVOM,
PRBSOM, PRBSMFOM,MFOOFOM
HDLC0IM,HDLC1IM,HDLC2IM,LCDIM,
1SECIM, 5SECIM, BIOIM, SIGIM
NRZ, Res, RxA1-0, RxEQ2-0
Table 20 - Master Control 1 (Page 1) (T1)
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Zarlink Semiconductor Inc.
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Data Sheet
Bit
Name
Functional Description
7
ESF
Extended Super Frame. Setting this bit enables transmission and reception of the 24 frame
superframe DS1 protocol.
6
5
SLC96 SLC96 Mode Select. Setting this bit enables input and output of the Fs bit pattern on the TxDL
and RxDL pins. Frame synchronization is the same as in the case of D4 operation. The
transmitter will insert A and B bits every 6 frames after synchronizing to the Fs pattern clocked
into Txdl. Receive Fs bits are not monitored for the Framing Bit Error Counter.
CXC
Cross Check. Setting this bit in ESF mode enables a cross check of the CRC-6 remainder
before the frame synchronizer pulls into sync. This process adds at least 6 milliseconds to the
frame synchronization time. Setting this bit in D4 (not ESF) mode enables a check of the Fs
bits in addition to the Ft bits during frame synchronization
4 - 3 RS1- 0 Reframe Select 1 - 0. These bits set the criteria for an automatic reframe in the event of
framing bits errors. The combinations available are:
RS1 - 0, RS0 - 0 = sliding window of 2 errors out of 4.
RS1 - 0, RS0 - 1 = sliding window of 2 errors out of 5.
RS1 - 1, RS0 - 0 = sliding window of 2 errors out of 6.
RS1 - 1, RS0 - 1 = no reframes due to framing bit errors.
2
1
FSI
Fs Bit Include. Only applicable in D4 mode (not ESF or SLC96). Setting this bit causes
errored Fs bits to be included as framing bit errors. A bad Fs bit will increment the Framing
Error Bit Counter, and will potentially cause a reframe (if it is the second bad framing bit out of
5). The Fs bit of the receive frame 12 will only be included if D4SECY is set.
ReFR
Reframe. A low - to - high transition on this bit causes an automatic reframe.
0
MFReFR MultiFrame Reframe. Only applicable in D4 or SLC96 mode. A low - to - high transition on this
bit causes an automatic multiframe reframe. The signaling bits are frozen until multiframe
synchronization is achieved. Terminal frame synchronization is not affected.
Table 21 - Framing Mode Select (T1)
(Page 1, Address 10H)
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Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Bit
Name
Functional Description
7
ESFYEL ESF Yellow Alarm. Setting this bit while in ESF mode causes a repeating pattern of eight 1’s
followed by eight 0’s to be inserted onto the transmit FDL (Japan Telecom bit set low - see
Signalling Control Word) or sixteen 1’s (Japan Telecom bit set high).
6
TXSECY Transmit Secondary D4 Yellow Alarm. Setting this bit (in D4 mode) causes the S bit of
transmit frame 12 to be set.
5
4
D4YEL D4 Yellow Alarm. When set bit 2 of all DS0 channels are forced low.
TxAO
Transmit All Ones. When low, this control bit forces a framed or unframed (depending on the
state of Transmit Alarm Control bit 0) all ones to be transmit at TTIP and TRING.
3
2
1
LUA
Loop Up Activate. Setting this bit forces transmission of a framed or unframed (depending on
the state of Transmit Alarm Control bit 0) repeating pattern of 00001.
LDA
Loop Down Activate. Setting this bit forces transmission of a framed or unframed (depending
on the state of Transmit Alarm Control bit 0) repeating pattern of 001.
D4SECY D4 Secondary Alarm. Set this bit for trunks employing the secondary Yellow Alarm. The Fs bit
in the 12th frame will not be used for counting errored framing bits. If a one is received in the Fs
bit position of the 12th frame a Secondary Yellow Alarm Detect bit will be set.
0
SO
Overhead bits Override. If set, this bit forces the overhead bits to be inserted as an overlay on
any of the following alarm conditions: i) transmit all ones, ii) loop up code insertion, iii) loop
down code insertion.
Table 22 - Transmit Alarm Control Word (T1)
(Page 1, Address 11H)
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Data Sheet
Bit
Name
Functional Description
7
EDL
Enable Data Link. Setting this bit multiplexes the serial stream clocked in on pin TxDL into
the FDL bit position (ESF mode) or the Fs position (D4 mode).
6
BIOMEn Bit Oriented Messaging Enable. Setting this bit enables transmission of bit - oriented
messages on the ESF facility data link. The actual message transmit at any one time is
contained in the BIOMTx register (page 1, address 13H). The receive bit - oriented message
register is always active, although the interrupt associated with it may be masked.
5
4
EXZ
Excess Zeros. Setting this bit causes each occurrence of received excess zeros to increment
the Line Code Violation Counter. Excess zeros are defined as 8 or more successive zeros for
B8ZS encoded data, or 16 or more successive zeros for non-B8ZS encoded data.
TxPDVS Transmit Pulse Density Violation Screen. Setting this bit causes ones to be injected into
the transmit data in the event that a violation of the ones density requirement is detected in
the outgoing data.
3
2
TxSYNC Transmit Synchronization. Setting this bit causes the transmit multiframe boundary to be
internally synchronized to the incoming Sbits on DSTi channel 31 bit 0.
TRSP
Transparent Mode. Setting this bit causes unframed data to be transmit from DSTi channels
0 to 23 and channel 31 bit 0 to be transmit transparently onto the DS1 line. Unframed data
received from the DS1 line is piped out on DSTo channels 0 to 23 and channel 31 bit 0.
1
0
JTS
Japan Telecom Synchronization. Setting this bit forces the inclusion of Sbits in the CRC-6
calculation.
H1R64
HDLC Rate Select. Setting this pin high while an HDLC is activated on a timeslot enables
64 Kb/s operation. Setting this pin low while an HDLC is activated enables 56 Kb/s operation
(this prevents data corruption due to forced bit stuffing).
Table 23 - Data Link Control Word (T1)
(Page 1, Address 12H)
Bit
Name
Functional Description
7 - 0 BIOMTx7-0 Transmit Bit Oriented Message. The contents of this register are concatenated with a
sequence of eight 1’s and continuously transmit in the FDL bit position of ESF trunks.
Normally the leading bit (bit 7) and last bit (bit 0) of this register are set to zero.
Table 24 - Transmit Bit Oriented Message (T1)
(Page 1, Address 13H)
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Data Sheet
Bit
Name
Functional Description
7
6
5
DSToEn DSTo Enable. If zero pin DSTo is tristate. If set the pin DSTo is enabled.
CSToEn CSTo Enable. If zero pin CSTo is tristate. If set the pin CSTo is enabled.
RBEn
DBEn
MSN
Robbed Bit signaling Enable. Setting this bit multiplexes the AB or ABCD signaling bits into
bit position 8 of all DS0 channels every 6th frame.
4
3
Debounce Enable. Setting this bit causes incoming signaling bits to be debounced for a
period of 6 to 9 milliseconds before reporting on CSTo or in the Receive signaling Bits Page.
Most Significant Nibble. If set to one the most significant nibble of CSTi and CSTo are
activated. The reporting stream CSTo contains the signaling information for the equivalent
channel in the most significant nibble, and least significant nibble is tristate. If set to zero the
least significant nibble is active for CSTi and CSTo and the most significant nibble of CSTo is
tristate.
2-1
SM1-0
JYEL
signaling Message. These two bits are used to fill the vacant bit positions available on
CSTo when the 3VJET is operating on a D4 trunk. The first two bits of each reporting nibble
of CSTo contain the AB signaling bits. The last two will contain SM1 and SM0 (in that order).
When the 3VJET is connected to ESF trunks four signaling bits (ABCD) are reported and the
bits SM1-0 become unused.
0
Japan Yellow Alarm Set this bit high to selects a pattern of 16 ones (111111111111111) as
the ESF yellow alarm, both for the case when an ESF yellow alarm is to be transmitted, or in
recognizing a received yellow alarm.
Table 25 - Signaling Control Word (T1)
(Page 1, Address 14H)
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Zarlink Semiconductor Inc.
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Data Sheet
Bit
Name
Functional Description
7
6
RxB8ZS Receive B8ZS Enable. If one, receive B8ZS decoding is enabled.
MLBK
Metallic Loopback. If one, then RRTIP/RRING are connected directly to TTIP and TRING
respectively. If zero, then this feature is disabled.
5
4
TxB8ZS Transmit B8ZS Enable. If one, all zero octets are substituted with B8ZS codes.
FBS
Forced Bit Stuffing. If set any transmit DS0 channel containing all zeros has bit 7 forced
high.
3
DLBK
Digital Loopback. If one, then the digital stream to the transmit LIU is looped back in place
of the digital output of the receive LIU. Data coming out of DSTo will be a delayed version of
DSTi. If zero, this feature is disabled.
2
1
0
RLBK
SLBK
PLBK
Remote Loopback. If one, then all time slots received on RRTIP/RRING are connected to
TTIP/TRING on the DS1 side of the 3VJET. If zero, then this feature is disabled.
ST-BUS Loopback. If one, then all time slots of DSTi are connected to DSTo on the ST-BUS
side of the 3VJET. If zero, then this feature is disabled. See Loopbacks section.
Payload Loopback. If one, then all time slots received on RTIP/RRING are connected to
TTIP/TRING on the ST-BUS side of the 3VJET. If zero, then this feature is disabled.
Table 26 - Coding and Loopback Control Word (T1)
(Page 1, Address 15H)
Bit
Name
Functional Description
7-0
TxSD7-0 Transmit Set Delay Bits 7-0. Writing to this register forces a one time setting of the delay
through the transmit slip buffer. The delay is defined as the time interval between the write of
the transmit STBUS channel containing DS1 timeslot 1 and its subsequent read. The delay
is modified by moving the position of the internally generated DS1 frame boundary. The
delay (when set) will always be less than 1 frame (125 uS). This register must be
programmed with a non - zero value.
Table 27 - Transmit Elastic Buffer Set Delay Word (T1)
(Page 1, Address 17H)
Bit
Name
Functional Description
7-0
TxM7-0 Transmit Message Bits 7 - 0. The contents of this register are transmit into those outgoing
DS1 channels selected by the Per Time Slot Control registers.
Table 28 - Transmit Message Word (T1)
(Page 1, Address 18H)
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Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Bit
Name
Functional Description
7
BPVE
Bipolar Violation Error Insertion. A zero-to-one transition of this bit inserts a single bipolar
violation error into the transmit DS1 data. A one, zero or one-to-zero transition has no
function.
6
5
CRCE
FTE
CRC-6 Error Insertion. A zero-to-one transition of this bit inserts a single CRC-6 error into
the transmit ESF DS1 data. A one, zero or one-to-zero transition has no function.
Terminal Framing Bit Error Insertion. A zero-to-one transition of this bit inserts a single
error into the transmit D4 Ft pattern or the transmit ESF framing bit pattern (in ESF mode). A
one, zero or one-to-zero transition has no function.
4
FSE
Signal Framing Bit Error Insertion. A zero-to-one transition of this bit inserts a single error
into the transmit Fs bits (in D4 mode only). A one, zero or one-to-zero transition has no
function.
3
2
1
0
LOSE
PERR
L32Z
Loss of Signal Error Insertion. If one, the 3VJET transmits an all zeros signal (no pulses).
Zero code suppression is overridden. If zero, data is transmitted normally.
Payload Error Insertion. A zero - to - one transition of this bit inserts a single bit error in the
transmit payload. A one, zero or one-to-zero transition has no function.
Digital Loss of Signal Selection. If one, the threshold for digital loss of signal is 32
successive zeros. If zero, the threshold is set to 192 successive zeros.
LOS/LOF Loss of Signal or Loss of Frame Selection. If one, pin LOS will go high when a loss of
signal state exits (criteria as per LLOS status bit). If low, pin LOS will go high when either a
loss of signal or a loss of frame alignment state exits.
Table 29 - Error Insertion Word (T1)
(Page 1, Address 19H)
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Data Sheet
Bit Name
Functional Description
7
RST
Software reset. Setting this bit is equivalent to performing a hardware reset. All counters are
cleared and the control registers are set to their default values. This control bit is internally
cleared after the reset operation is complete.
6
5
SPND Suspend Interrupts. If one, the IRQ output will be in a high-impedance state and all interrupts
will be ignored. If zero, the IRQ output will function normally.
INTA
Interrupt Acknowledge. Setting this pin clears all interrupts and forces the IRQ pin into high
impedance. The control bit itself is then internally cleared.
4
3
CNTCLR Counter Clear. If one, all status error counters are cleared and held low.
SAMPLE One Second Sample. Setting this bit causes the error counters (change of frame alignment, loss
of frame alignment, LCV errors, CRC errors, severely errored frame events and multiframes out
of sync) to be updated on one second intervals coincident with the one second timer (status page
3 address 12H bit 7).
2
OOFP Out of Frame Pause. If set high, this bit will suspend operation of the Line Code VIolation
Counter during an out - of - frame condition; upon achieving terminal frame synchronization the
counter will resume normal operation. If set low, the Line Code Violation counter will continue to
count errors even if terminal frame synchronization is lost.
1
0
--
Reserved. Set to zero for normal operation.
D20
Double20. Set to zero for normal operation. Set high to double clock speed in the HDLC,
speeding up microport accesses from 160 ns between consecutive reads/writes to 80 ns
between consecutive reads/writes.
Table 30 - Reset Control Word (T1)
(Page 1, Address 1AH)
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Data Sheet
Bit
Name
Functional Description
7
TFSYNIM Terminal Frame Synchronization Interrupt Mask. When unmasked an interrupt is initiated
whenever a change of state of loss of terminal frame synchronization condition exists. If 1
-unmasked, 0 - masked.
6
5
MFSYNIM Multiframe Synchronization Interrupt Mask. When unmasked an interrupt is initiated
whenever a change of state of loss of multiframe synchronization condition exist. If 1 -
unmasked, 0 - masked
BIOMTIM Bit Oriented Message Transition Interrupt Mask. When unmasked an interrupt is initiated
whenever a new BIOM arrives or if the current BIOM stops transmission. If 1 - unmasked, 0
-masked.
4
3
2
1
0
AISIM
Alarm Indication Signal Interrupt Mask. When unmasked a change of state of received all
ones condition will initiate an interrupt. If 1 - unmasked, 0 - masked.
LOSIM Loss of Signal Interrupt Mask. When unmasked an interrupt is initiated whenever a change of
state of a loss of signal condition exists. If 1 - unmasked, 0 - masked.
SEFIM
Severely Errored Frame Interrupt Mask. When unmasked an interrupt is initiated when a
sequence of 2 framing errors out of 6 occurs. If 1 - unmasked, 0 - masked.
TxSLPIM Transmit SLIP Interrupt Mask. When unmasked an interrupt is initiated whenever a controlled
frame slip occurs in the transmit elastic buffer. If 1 - unmasked, 0 - masked.
RxSLPIM Receive SLIP Interrupt Mask. When unmasked an interrupt is initiated whenever a controlled
frame slip occurs in the receive elastic buffer. If 1 - unmasked, 0 - masked.
Table 31 - Interrupt Mask Word Zero (T1)
(Page 1, Address 1BH)
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Data Sheet
Bit Name
Functional Description
7
FEIM Framing Bit Error Interrupt Mask. When unmasked an interrupt is initiated whenever an
erroneous framing bit is detected (provided the circuit is in terminal frame sync). If 1 - unmasked,
0 - masked.
6
5
4
3
CRCIM CRC-6 Error Interrupt Mask. When unmasked an interrupt is initiated whenever a local CRC-6
error occurs. If 1 - unmasked, 0 - masked.
YELIM Yellow Alarm Interrupt Mask. When unmasked detection of a yellow alarm triggers an interrupt.
If 1 - unmasked, 0 - masked.
COFAIM Change of Frame Alignment Interrupt Mask. When unmasked an interrupt is initiated whenever
a change of frame alignment occurs after a reframe. If 1 - unmasked, 0 - masked.
LCVIM Line Code Violation Interrupt Mask. When unmasked an interrupt is initiated whenever a line
code violation (excluding B8ZS bipolar violations encoding) is encountered. If 1- unmasked, 0 -
masked.
2
PRBSIM Pseudo Random Bit Sequence Error Interrupt Mask. When unmasked an interrupt will be
generated upon detection of an error with a channel selected for PRBS testing. If 1 - unmasked, 0
- masked.
1
0
PDVIM Pulse Density Violation Interrupt Mask. When unmasked an interrupt is triggered whenever a
sequence excess consecutive zeros is received on the line. If 1 - unmasked, 0 - masked.
- - -
Unused.
Table 32 - Interrupt Mask Word One (T1)
(Page 1, Address 1CH)
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Data Sheet
Bit
Name
Functional Description
7
FEOM
Framing Bit Error Counter Overflow Interrupt Mask. When unmasked an interrupt is
initiated whenever the framing bit error counter changes from FFH to 00H. If 1 - unmasked,
0 - masked.
6
5
CRCOM
OOFOM
CRC-6 Error Counter Overflow Interrupt Mask. When unmasked an interrupt is initiated
whenever the CRC-6 error counter changes from FFH to 00H. If 1 - unmasked, 0 - masked.
Out Of Frame Counter Overflow Interrupt Mask. When unmasked an interrupt is initiated
whenever the out of frame counter changes state from changes from FFH to 00H. If 1 -
unmasked, 0 - masked.
4
3
2
1
0
COFAOM Change of Frame Alignment Counter Overflow Interrupt Mask. When unmasked an
interrupt is initiated whenever the change of frame alignment counter changes from FFH to
00H. If 1 - unmasked, 0 - masked.
LCVOM
Line Code Violation Counter Overflow Interrupt Mask. When unmasked an interrupt is
initiated whenever the line code violation counter changes from FFH to 00H. If 1-
unmasked, 0 - masked.
PRBSOM Pseudo Random Bit Sequence Error Counter Overflow Interrupt Mask. When
unmasked an interrupt will be generated whenever the PRBS error counter changes from
FFH to 00H. If 1 - unmasked, 0 - masked.
PRBSMFOM Pseudo Random Bit Sequence Multiframe Counter Overflow Interrupt Mask. When
unmasked an interrupt will be generated whenever the multiframe counter attached to the
PRBS error counter overflows. FFH to 00H. If 1 - unmasked, 0 - masked.
MFOOFOM Multiframes Out Of Sync Overflow Interrupt Mask. When unmasked an interrupt will be
generated when the multiframes out of frame counter changes from FFH to 00H. If 1 -
unmasked, 0 - masked.
Table 33 - Interrupt Mask Word Two (T1)
(Page 1, Address 1DH)
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Data Sheet
Bit
Name
Functional Description
7
HDLC0IM HDLC0 Interrupt Mask. When unmasked an interrupt is triggered by an unmasked event
in HDLC0. If 1 - unmasked, 0 - masked.
6
5
4
HDLC1IM HDLC1 Interrupt Mask. When unmasked an interrupt is triggered by an unmasked event
in HDLC1. If 1 - unmasked, 0 - masked.
HDLC2IM HDLC2 Interrupt Mask. When unmasked an interrupt is triggered by an unmasked event
in HDLC2. If 1 - unmasked, 0 - masked.
LCDIM
Loop Code Detected Interrupt Mask. When unmasked an interrupt is triggered when
either the loop up (00001) or loop down (001) code has been detected on the line for a
period of 48 milliseconds. If 1 - unmasked, 0 - masked.
3
1SECIM One Second Status Interrupt Mask. When unmasked an interrupt is initiated when the
1SEC status bit (page 3 address 12H bit 7) goes from low to high. If 1 - unmasked, 0 -
masked.
2
1
5SECIM Five Second Status Interrupt Mask. When unmasked an interrupt is initiated when the 5
SEC status bit goes from low to high. If 1 - unmasked, 0 - masked.
BIOMIM Bit Oriented Message Interrupt Mask. When unmasked an interrupt is initiated when a
pattern 111111110xxxxxx0 has been received on the FDL that is different from the last
message. The new message must persist for 8 out the last 10 message positions to be
accepted as a valid new message. If 1- unmasked, 0 - masked.
0
SIGIM
signaling Interrupt Mask. When unmasked an interrupt will be initiated when a change of
state (optionally debounced - see DBEn in the Data Link, signaling Control Word page 1
address 12H) is detected in the signaling bits (AB or ABCD) pattern. If 1 - unmasked, 0 -
masked.
Table 34 - Interrupt Mask Word Three (T1)
(Page 1, Address 1EH)
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Data Sheet
Bit
Name
Functional Description
7
NRZ
NRZ Format Selection. Only used in the digital framer only mode (LIU is disabled). A one
sets the MT9076 to accept a unipolar NRZ format input stream on RxA as the line input,
and to transmit a unipolar NRZ format stream on TxB. A zero causes the MT9076 to accept
a complementary pair of dual rail inputs on RxA/RxB and to transmit a complementary pair
of dual rail outputs on TxA/TxB.
6
5
- - -
Reserved. Set this low for normal operation.
Res
Resistor. Set this bit high to connect a 104 ohm internal resistor between RTIP and
RRING. This is activated where an external 20.8 ohm terminating resistor is in use on a T1
line.
4 - 3
RxA1-0
Automatic Receive Equalizer Control. These bits should be programmed according to
the table below:
00
11
Equalization will be activated using the control bits RxEQ2-0.
The receive equalizer is turned on and will compensate for loop length
automatically. The control bits RxEQ2-0 will be ignored.
01, 10 Reserved for factory purposes.
2 - 0
RxEQ2-0 Receive Equalization Select. Setting these pins forces a level of equalization of the
incoming line data.
RES2 RES1 RES0 Receive Equalization
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
none
8 dB
16 dB
24 dB
32 dB
40 dB
48 dB
reserved
These settings have no effect if either of RxA1 and RxA0 are set to one.
Table 35 - LIU Receiver Word (T1)
(Page 1, Address 1FH)
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Data Sheet
20.1.2 Master Control 2 (Page 02H) (T1)
Address
Register
Names
(A4A3A2A1A0)
10H (Table 37) Configuration Control Word
11H (Table 38) LIU Tx Word
T1/E1, TxEN, LIUEn, ELOS, Tx8KEN, ADSEQ
CPL, TxLB2-0
12H
Reserved
Set all bits to zero for normal operation.
13H (Table 39) Jitter Attenuator Control Word
JFC, JFD2-JFD0, JACL
14H
15H
Reserved
Reserved
Set all bits to zero for normal operation.
Set all bits to zero for normal operation.
16H (Table 40) Equalizer High Threshold
17H (Table 41) Equalizer Low Threshold
18H (Table 42) Serial Config. Word
19H (Table 43) HDLC0 Select
EHT7-0
ELT7-0
IMA, T1DM, G.802, 8Men, 8MTS1-0
En, FDLSEL, CH4-0
En, CH4-0
En, CH4-0
CP6-0
1AH (Table 44) HDLC1 Select
1BH (Table 45) HDLC2 Select
1CH (Table 46) Custom Pulse Word 1
1DH (Table 47) Custom Pulse Word 2
1EH (Table 48) Custom Pulse Word 3
1FH (Table 49) Custom Pulse Word 4
CP6-0
CP6-0
CP6-0
Table 36 - Master Control 2 (Page 02H) (T1)
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Data Sheet
Bit Name
Functional Description
7
T1/E1
T1/E1 mode selection. when this bit is zero, the device is in T1 mode. When set high, the device
is in E1 mode.
6
5
--
Reserved. Must be kept at 0 for normal operation.
TxEN
Transmit Enable. Setting this bit low turns off the TTIP and TRING output line drivers. Setting this
bit high enables them.
4
LIUEn
LIU Enable. Setting this bit low enables the internal LIU front-end. Setting this pin high disables
the LIU. Digital inputs RXA and RXB are sampled by the rising edge of E1.5i (Exclk) to strobe in
the received line data. Digital transmit data is clocked out of pins TXA and TXB with the rising edge
of Exclk
3
2
ELOS
ELOS Enable. Set this bit low to set the analog loss of signal threshold to 40 dB below nominal.
Set this bit high to set the analog loss of signal threshold to 20 dB below nominal.
Tx8KEN Transmit 8 KHz Enable. If one, the pin RxMF/TxFP transmits a positive 8 KHz frame pulse
synchronous with the serial data stream transmit on TXA/TXB. If zero, the pin RxMF/TxFP
transmits a negative frame pulse synchronous with the multiframe boundary of data coming out of
DSTo.
1
0
ADSEQ Digital Milliwatt or Digital Test Sequence. If one, the A law digital milliwatt analog test sequence
will be selected for those channels with per time slot control bits TTST, RRST set. If zero, a PRBS
generator / detector will be connected to channels with TTST, RRST respectively.
--
Reserved. Must be kept at 0 for normal operation.
Table 37 - Configuration Control Word
(Page 2, Address 10H) (T1)
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Data Sheet
Bit
Name
Functional Description
7-5
4
--
--
Reserved. Must be kept at 0 for normal operation.
Reserved. Set low for normal operation.
3
CPL
Custom Pulse Level. Setting this bit low enables the internal ROM values in generating the
transmit pulses. The ROM is coded for different line terminations or build out, as specified in the
LIU Control word. Setting this pin high disables the pre-programmed pulse templates. Each of
the 4 phases that generate a mark derive their D/A coefficients from the values programmed in
the CPW registers.
2-0 TXLB2-0 Transmit Line Build Out 2 - 0. Setting these bits shapes the transmit pulse as detailed in the
table below:
TX22
TXL1
TXL0
Line Build Out
0 to 133 feet/ 0 dB
133 to 266 feet
266 to 399 feet
399 to 533 feet
533 to 655 feet
-7.5 dB
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
-15 dB
-22.5 dB
After reset these bits are zero.
Table 38 - LIU Tx Word
(Page 2, Address 11H) (T1)
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Data Sheet
Bit
Name
Functional Description
7
6
- - -
Unused.
JFC
Jitter Attenuator FIFO Centre. When this bit is toggled the read pointer on the jitter
attenuator shall be centered. During this centering the jitter on the JA outputs is increased
by 0.0625 U.I. This feature is only available when IMA Mode is activated.
5 - 3 JFD2-JFD0 Jitter Attenuator FIFO Depth Control Bits. These bits determine the depths of the jitter
attenuator FIFO as shown below:
JFD2
JFD1
JFD0
Depth
16
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
32
48
64
80
96
112
128
This feature is only available when IMA Mode is activated.
2
JACL
- - -
Jitter Attenuator FIFO Clear Bit. If one, the Jitter Attenuator, its FIFO and status are reset.
The status registers will identify the FIFO as being empty. However, the actual bit values of
the data in the JA FIFO will not be reset.
This feature is only available when IMA Mode is activated.
1 - 0
Unused.
Table 39 - Jitter Attenuation Control Word
(Page 2, Address 13H) (T1)
Bit
Name
Functional Description
7-0
EHT7-0
Equalizer High Threshold. These bits set the highest possible binary count tolerable
coming out of the equalized signal peak detector before a lower level of equalization is
selected. This register is only used when A/D based automatic equalization is selected
using the Rx LIU Control Word. Recommended value to program is 10111011.
Table 40 - Equalizer High Threshold
(Page 2, Address 16H) (T1)
Bit
Name
Functional Description
7-0
ELT7-0
Equalizer Low Threshold. These bits set the lowest possible binary count tolerable coming
out of the equalized signal peak detector before a higher level of equalization is selected.
This register is only used when A/D based automatic equalization is selected using the Rx
LIU Control Word. Recommended value to program is 00110000.
Table 41 - Equalizer Low Threshold
(Page 2, Address 17H) (T1)
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Data Sheet
Bit
Name
Functional Description
Reserved. Must be kept at 0 for normal operation.
7-6
5
--
IMA
Inverse Mux Mode. Setting this bit high the I/O ports to allow for easy connection to the
Zarlink MT90220. DSTi becomes a serial 1.544 data stream. C4b becomes a 1.544 MHz
clock that clocks DSTi in on the falling edge. RXFP becomes a positive framing pulse that is
high for the first bit (the framing bit) of the serial T1 stream coming from the pin DSto. This
stream is clocked out on the rising edge of Exclk. Set this pin low for all other applications.
4
3
--
Reserved. Must be set to 0 for normal operation.
G.802
G.802. Must be kept at 0 for normal operation. Set high for ST-BUS to DSI channel mapping
as per G.802.
2
8Men
8 Mb/s Bit Rate Select. Setting this bit low enables a serial bit rate on DSTi, CSTi and
DSTo, CSTo of 2.048 Mb/s. Setting this bit high enables a gapped serial bit rate of
8.192 Mb/s on DSTi, CSTi, DSTo and CSTo.
1-0
8MTS1-0 8 Mb/s Time Slot Select. These two bits select the active timeslots on the serial 8.192 Mb/s
channels. During the active timeslots incoming serial data on DSTi and CSTi is clocked into
the device, and data is clocked out onto DSTo and CSTo. During inactive timeslots DSTo
and CSTo are tristate. For all selections every fourth 8 Mb/s timeslot is active for the first 96
timeslots (24 x 8).
The timeslot selection (T1 mode) is as follows:
8MTS1 8MST0
Active timeslots
0 0
0 1
1 0
1 1
0,4,8,12,16,20,24,28,32,36,40,44,48,52,56,60,64,68,72,76,80,84,88,92
1,5,9,13,17,21,25,29,33,37,41,45,49,53,57,61,65,69,73,77,81,85,89,93
2,6,10,14,18,22,26,30,34,38,42,46,50,54,58,62,66,70,74,78,82,86,90,94
3,7,11,15,19,23,27,31,35,39,43,47,51,55,59,63,67,71,75,79,83,87,91,95
Table 42 - Serial Config. Word
(Page 2, Address 18H) (T1)
Bit
Name
Functional Description
7
En
Enable. Set high to attach the HDLC0 controller to the channel specified below. Set low to
disconnect the HDLC0.
6
FDLSEL
Facility Data Link Select. Set this bit to 0 to attach HDLC0 to the 4 kb/s facility data link.
Set this bit to 1 to attach HDLC0 to a payload timeslot.
5
--
Reserved. Must be kept at 0 for normal operation.
4-0
CH4-0
Channel 4-0. This 5 bit number specifies the channel time HDLC0 will be attached to if
enabled. Channel 0 is the first channel in the frame. Channel 23 is the last channel available
in a T1 frame. If enabled in a channel, HDLC data will be substituted for data from DSTi on
the transmit side. Receive data is extracted from the incoming line data before the elastic
buffer.
Table 43 - HDLC0 Select
(Page 2, Address 19H) (T1)
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Data Sheet
Bit
Name
Functional Description
7
En
Enable. Set high to attach the HDLC1 controller to the channel specified below. Set low to
disconnect the HDLC1.
6-5
4-0
--
Reserved. Must be kept at 0 for normal operation.
CH4-0
Channel 4-0. This 5 bit number specifies the channel time HDLC1 will be attached to if
enabled. Channel 0 is the first channel in the frame. Channel 23 is the last channel available
in a T1 frame. If enabled in a channel, HDLC data will be substituted for data from DSTi on
the transmit side. Receive data is extracted from the incoming line data before the elastic
buffer.
Table 44 - HDLC1 Select
(Page 2, Address 1AH) (T1)
Bit
Name
Functional Description
7
En
Enable. Set high to attach the HDLC2 controller to the channel specified below. Set low to
disconnect the HDLC2.
6-5
4-0
- -
Reserved. Must be kept at 0 for normal operation.
CH4-0
Channel 4-0. This 5 bit number specifies the channel time HDLC2 will be attached to if
enabled. Channel 0 is the first channel in the frame. Channel 23 is the last channel available
in a T1 frame. If enabled in a channel, HDLC data will be substituted for data from DSTi on
the transmit side. Receive data is extracted from the incoming line data before the elastic
buffer.
Table 45 - HDLC2 Select
(Page 2, Address 1BH) (T1)
Bit
Name
Functional Description
7
- -
Reserved. Must be kept at 0 for normal operation.
6-0
CP6-0
Custom Pulse. These bits provide the capability for programming the magnitude setting for
the TTIP/TRING line driver A/D converter during the first phase of a mark. The greater the
binary number loaded into the register, the greater the amplitude driven out. This feature is
enabled when the control bit 3 - CPL of the Custom Tx Pulse Enable Register - address 11H
of Page 2 is set high.
Table 46 - Custom Pulse Word 1
(Page 2, Address 1CH) (T1)
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Data Sheet
Bit
Name
Functional Description
Reserved. Must be kept at 0 for normal operation.
7
-
6-0
CP6-0
Custom Pulse. These bits provide the capability for programming the magnitude setting
for the TTIP/TRING line driver A/D converter during the second phase of a mark. The
greater the binary number loaded into the register, the greater the amplitude driven out.
This feature is enabled when the control bit 3 - CPL of the Custom Tx Pulse Enable
Register - address 11H of Page 2 is set high.
Table 47 - Custom Pulse Word 2
(Page 2, Address 1DH) (T1)
Bit
Name
Functional Description
7
- -
Reserved. Must be kept at 0 for normal operation.
6-0
CP6-0
Custom Pulse. These bits provide the capability for programming the magnitude setting for
the TTIP/TRING line driver A/D converter during the third phase of a mark. The greater the
binary number loaded into the register, the greater the amplitude driven out. This feature is
enabled when the control bit 3 - CPL of the Custom Tx Pulse Enable Register - address 11H
of Page 2 is set high.
Table 48 - Custom Pulse Word 3
(Page 2, Address 1EH) (T1)
Bit
Name
Functional Description
7
- -
Reserved. Must be kept at 0 for normal operation.
6-0
CP6-0
Custom Pulse. These bits provide the capability for programming the magnitude setting for
the TTIP/TRING line driver A/D converter during the fourth phase of a mark. The greater the
binary number loaded into the register, the greater the amplitude driven out. This feature is
enabled when the control bit 3 - CPL of the Custom Tx Pulse Enable Register - address 11H
of Page 2 is set high.
CP6-0 Breakdown
CP[6]
Sign bit (0=neg, 1=pos)
(only necessary for T1)
CP[5:0]
Magnitude in binary (pulse amplitude = 0.1 * CP[5:0]V)
Table 49 - Custom Pulse Word 4
(Page 2, Address 1FH) (T1)
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Data Sheet
20.1.3 Master Status 1 (Page03H) (T1)
Address
Register
Function
(A4A3A2A1A0)
10H (Table 51)
11H (Table 52)
Synchronization Status Word
Alarm Status Word
TFSYNC, MFSYNC, SE, LOS
D4YALM, D4Y48, SECYEL, ESFYEL, BLUE,
PDV, LLED, LLDD
12H (Table 53)
13H (Table 54)
14H (Table 55)
15H (Table 56)
16H (Table 57)
17H (Table 58)
18H (Table 59)
19H
Timer Status Word
1SEC, 2SEC, 5SEC
RSLIP, RSLPD, RxFRM, RxFT, RxSBD2-0
RxTS4-0, RxBC2-0
RxBOM7-0
Most Significant Phase Status Word
Least Significant Phase Status Word
Receive Bit Oriented Message
Receive Signal Status Word
LLOS
MSB Transmit Slip Buffer
TSLIP, TSLPD, TxSBMSB
TxTS4-0, TxBC2-0
Unused.
Transmit Slip Buffer Delay
- - -
1AH
- - -
Unused.
1BH
- - -
Unused.
1CH
- - -
Reserved.
1DH (Table 60)
1EH
Analog Peak Detect
- - -
AP7-0
Reserved
1FH (Table 61)
Identification Word
Internally set to 01111000
Table 50 - Master Status 1 (Page 3) (T1)
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Data Sheet
Bit
Name
Functional Description
7
TFSYNC Terminal Frame Synchronization. Indicates the Terminal Frame Synchronization status (1
- loss; 0 - acquired). For ESF links terminal frame synchronization and multiframe
synchronization are synonymous.
6
5
MFSYNC Multiframe Synchronization. Indicates the Multiframe Synchronization status (1 - loss; 0
-acquired). For ESF links multiframe synchronization and terminal frame synchronization
are synonymous.
SE
LOS
- - -
Severely Errored Frame. This bit toggles when 2 of the last 6 received framing bits are in
error. The framing bits monitored are the ESF framing bits for ESF links, the Ft bits for
SLC-96 links and a combination of Ft and Fs bits for D4 links (See Framing Mode Selection
Word - page 1 address 10H).
4
Digital Loss Of Signal. This bit goes high after the detection of a string of consecutive
zeros. It returns low when the incoming pulse density exceeds 12.5% over a 250 ms period.
The threshold for this condition is set by the control bit L32Z. If L32Z is set high the threshold
is 32 successive zeros. If L32Z is set low the threshold is 192 successive zeros.
3 - 0
Unused.
Table 51 - Synchronization Status Word
(Page 3, Address 10H) (T1)
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Data Sheet
Bit
Name
Functional Description
7
D4YALM D4 Yellow Alarm. This bit is set if bit position 2 of virtually every DS0 channel is a zero for a
period of 600 milliseconds. The alarm is tolerant of errors by permitting up to 16 ones in a 48
millisecond integration period. The alarm clears in 200 milliseconds after being removed
from the line.
6
D4Y48
D4 Yellow Alarm - 48 millisecond sample. This bit is set if bit position 2 of virtually every
DS0 channel is a zero for a period of 48 milliseconds. The alarm is tolerant of errors by
permitting up to 16 ones in the integration period. This bit is updated every 48 milliseconds.
5
4
SECYEL Secondary D4 Yellow Alarm. This bit is set if 2 consecutive’1’s are received in the Sbit
position of the 12th frame of the D4 superframe.
ESFYEL
ESF Yellow Alarm. This bit is set if the ESF yellow alarm 0000000011111111 is receive in
seven or more codewords out of ten.
3
2
BLUE
PDV
Blue Alarm. This bit is set if less than 6 zeros are received in a 3 millisecond window.
Pulse Density Violation. This bit toggles if the receive data fails to meet ones density
requirements. If RXB8ZS is set high it will toggle upon detection of 8 zeros. I RxB8ZS is
set low it will toggle upon detection of 16 consecutive zeros on the line data, or if there
are less than N ones in a window of 8(N+1) bits - where N = 1 to 23.
1
0
LLED
LLDD
Line Loopback Enable Detect. This bit will be set when a framed or unframed repeating
pattern of 00001 has been detected during a 48 millisecond interval. Up to fifteen errors are
permitted per integration period.
Line Loopback Disable Detect. This bit will be set when a framed or unframed repeating
pattern of 001 has been detected during a 48 millisecond interval. Up to fifteen errors are
permitted per integration period.
Table 52 - Alarm Status Word
(Page 3, Address 11H) (T1)
Bit
Name
Functional Description
7
6
1SEC
2SEC
One Second Timer Status. This bit changes state once every 0.5 seconds.
Two Second Timer Status. This bit changes state once every second and is synchronous
with the 1SEC timer.
5
5SEC
- - -
Five Second Timer Status. This bit changes state once every 2.5 seconds and is
synchronous with the 1SEC timer.
4-0
Unused.
Table 53 - Timer Status Word
(Page 3, Address 12H) (T1)
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Data Sheet
Bit
Name
Functional Description
7
RSLIP
Receive Slip. A change of state (i.e., 1-to-0 or 0-to-1) indicates that a receive controlled
frame slip has occurred.
6
5
RSLPD
RxFRM
Receive Slip Direction. If one, indicates that the last received frame slip resulted in a
repeated frame, i.e., the system clock (C4b) is faster than network clock (E2o). If zero,
indicates that the last received frame slip resulted in a lost frame, i.e., system clock slower
than network clock. Updated on an RSLIP occurrence basis.
Receive Frame Delay. The most significant bit of the Receive Slip Buffer Phase Status
Word. If one, the delay through the receive elastic buffer is greater than one frame in length;
if zero, the delay through the receive elastic buffer is less than one frame in length.
4
3
- - -
Unused.
RxFT
Receive Frame Toggle. This bit toggles on the falling edge of RxTS4. It is a Wink pulse.
2-0 RxSBD2-0 Receive Sub Bit Delay. The three least significant bits of the Receive Slip Buffer Phase
Status Word. They indicate the clock, half clock and one eighth clock cycle depth of the
phase status word sample point (bits 2, 1,0 respectively).
Table 54 - Most Significant Phase Status Word
(Page 3, Address 13H) (T1)
Bit
Name
Functional Description
7 - 3 RxTS4 - 0 Receive Time Slot. A five bit counter that indicates the number of time slots between the
receive elastic buffer internal write frame boundary and the ST-BUS read frame boundary.
The count is updated every 250 uS.
2 - 0 RxBC2 - 0 Receive Bit Count. A three bit counter that indicates the number of STBUS bit times there
are between the receive elastic buffer internal write frame boundary and the ST-BUS read
frame boundary. The count is updated every 250 uS.
Table 55 - Least Significant Phase Status Word
(Page 3, Address 14H) (T1)
Bit
Name
Functional Description
7 - 0 RxBOM7 - 0 Received Bit Oriented Message. This register contains the eight least significant bits of the
ESF bit oriented message codeword. The contents of this register is updated when a new bit
- oriented message codeword has been detected in 8 out of the last ten codeword positions.
Table 56 - Receive Bit Oriented Message
(Page 3, Address 15H) (T1)
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Data Sheet
Bit
Name
Functional Description
7
LLOS
LIU Loss of Signal indication. This bit will be high when the received signal is less than 40
dB below the nominal value for a period of at least 1 msec. This bit will be low for normal
operation.
6-0
- - -
Unused.
Table 57 - Receive Signal Status Word
(Page 3, Address 16H) (T1)
Bit
Name
Functional Description
7
TSLIP
Transmit Slip. A change of state (i.e., 1-to-0 or 0-to-1) indicates that a transmit controlled
frame slip has occurred.
6
TSLPD Transmit Slip Direction. If one, indicates that the last transmit frame slip resulted in a
repeated frame, i.e., the internally generated 1.544 MHz. transmit clock is faster than the
system clock (C4b). If zero, indicates that the last transmit frame slip resulted in a lost frame,
i.e., the internally generated 1.544 MHz. transmit clock is slower than network clock.
Updated on an TSLIP occurrence basis.
5
TxSBMSB Transmit Slip Buffer MSB. The most significant bit of the phase status word. If one, the
delay through the transmit elastic buffer is greater than one frame in length; if zero, the delay
through the receive elastic buffer is less than one frame in length. This bit is reset whenever
page 1 address 17H - Transmit Slip Buffer Delay - is written to.
4 - 0
- - -
Unused.
Table 58 - MSB Transmit Slip Buffer
(Page 3, Address 17H) (T1)
Bit
Name
Functional Description
7 - 3
TxTS4 - 0 Transmit Time Slot. A five bit counter that indicates the number of STBUS time slots
between the transmit elastic buffer STBUS write frame boundary and the internal transmit
read frame boundary. The count is updated every 250 uS.
2 - 0
TxBC2 - 0 Transmit Bit Count. A three bit counter that indicates the number of STBUS bit times
there are between the transmit elastic buffer STBUS write frame boundary and the internal
read frame boundary. The count is updated every 250 uS.
Table 59 - Transmit Slip Buffer Delay
(Page 3, Address 18H) (T1)
Bit
Name
Functional Description
7 - 0
AP7 - 0
Analog Peak. This status register gives the output value of an 8 bit A/D converter
connected to a peak detector on RTIP/RRING.
Table 60 - Analog Peak Detect
(Page 3, Address 1DH) (T1)
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Data Sheet
Bit
Name
Functional Description
7-0
ID7-0
ID Number. Contains device code 01111000
Table 61 - Identification Word
(Page 3, Address 1FH) (T1)
20.1.4 Master Status 2 (Page 04H) (T1)
Address
Register
Function
(A4A3A2A1A0)
10H (Table 63)
11H (Table 64)
12H (Table 65)
PRBS Error Counter
PS7-0
CRC Multiframe counter for PRBS
Alarm Reporting Latch
PSM7-0
D4YALML, D4Y48L, SECYELL, ESFYELL,
BLUEL, PDVL, LLEDL, LLDDL
13H (Table 66)
14H (Table 67)
Framing Bit Counter
FC7-0
Out of Frame / Change of Frame Alignment OOF3-0/COFA3-0
Counters
15H (Table 68)
16H (Table 69)
Multiframes Out of Sync Counter
MFOOF7-0
Most Significant Line Code Violation Error LCV15 - LCV8
Counter
17H (Table 70)
Least Significant Line Code Violation Error LCV7 - LCV0
Counter
18H (Table 71)
19H (Table 72)
1AH
CRC- 6 Error Counter (Address 18H)
CRC- 6 Error Counter (Address 19H)
CC15-CC8
CC7 - CC0
Unused.
1BH (Table 73)
Interrupt Word Zero
TFSYNI, MFSYNI, BIOMTI, AISI, LOSI, SEI,
TxSLPI, RxSLPI
1CH (Table 74)
1DH (Table 75)
Interrupt Word One
Interrupt Word Two
FEI, CRCI, YELI, COFAI, LCVI, PRBSI, PDVI
FEO, CRCO, OOFO, COFAO, LCVO, PRBSO,
PRBSMFO,MFOOFO
1EH (Table 76)
1FH (Table 77)
Interrupt Word Three
HDLC0I, HDLC1I, HDLC2I, LCDI, 1SECI,
5SECI, BIOMI, SIGI
Overflow Reporting Latch
FEOL, CRCOL, OOFOL, COFAOL, LCVOL,
PRBSOL, PRBSMFOL, MFOOFOL
Table 62 - Master Status 2 (Page 4) (T1)
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Data Sheet
Bit
Name
Functional Description
7 - 0
PS7-0
This counter is incremented for each PRBS error detected on any of the receive channels
connected to the PRBS error detector.
Table 63 - PRBS Error Counter
(Page 4, Address 10H) (T1)
Bit
Name
Functional Description
7 - 0 PSM7-0
This counter is incremented for each received CRC multiframe. It is cleared when the PRBS
Error Counter is written to.
Table 64 - CRC Multiframe Counter for PRBS
(Page 4, Address 11H) (T1)
Bit
Name
Functional Description
7
D4YALML D4 Yellow Alarm Latch. This bit is set if a D4 yellow alarm is detected within a 600
millisecond integration period. It is cleared after a read.
6
5
4
D4Y48L
D4 Yellow Alarm (48 milliseconds) Latch. This bit is set if a D4 yellow alarm is detected
within a 48 millisecond integration period. It is cleared after a read.
SECYELL Secondary D4 Yellow Alarm Latch. This bit is set if an alternate D4 (S bit in 12 the frame)
is detected. It is cleared after a read.
ESFYELL ESF Yellow Alarm Latch. This bit is set upon receipt of a ESF yellow alarm. It is cleared
after a read.
3
2
BLUEL
PDVL
Blue Alarm Latch. This bit is set upon receipt of a blue alarm. It is cleared after a read.
Pulse Density Violation Latch. This bit is set upon receipt of a pulse density violation. It is
cleared after a read.
1
0
LLEDL
LLDDL
Line Loopback Enable Detect Latch. This bit is set upon receipt of a line loopback enable
code. It is cleared after a read.
Line Loopback Disable Detect Latch. This bit is set upon receipt of a line loopback
disable code. It is cleared after a read.
Table 65 - Alarm Reporting Latch
(Page 4, Address 12H) (T1)
Bit
Name
Functional Description
7 - 0 FC7 - 0
Framing Bit Counter. This eight bit counter will be incremented for each error in the
received framing pattern. In ESF mode the ESF framing bits are monitored. In D4 mode Fs
bits may be monitored as well as Ft bits. See - Section 15.5 Framing Bit Counter. The count
is only active if the 3VJET is in synchronization.
Table 66 - Framing Bit Counter
(Page 4, Address 13H) (T1)
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Data Sheet
Bit
Name
Functional Description
7 - 4
OOF3 - 0 Out Of Frame Counter. This four bit counter is incremented with every loss of receive
frame synchronization.
3 - 0 COFA3 - 0 Change of Frame Alignment Counter. This four bit counter is incremented if a
resynchronization is done which results in a shift in the frame alignment position.
Table 67 - Out Of Frame / Change of Frame Alignment Counter
(Page 4, Address 14H) (T1)
Bit
Name
Functional Description
7 - 0 MFOOF7 - 0 Multiframes Out of Synchronization Counter. This eight bit counter will be incremented
once for every multiframe (1.5 milliseconds in D4 mode, 3 milliseconds in ESF mode) in
which basic frame synchronization is lost.
Table 68 - Multiframes Out of Sync Counter
(Page 4, Address 15H) (T1)
Bit
Name
Functional Description
7 - 0 LCV15 - 8
Most Significant Bits of the LCV Counter. The most significant eight bits of a 16 bit
counter that is incremented once for every line code violation error received.
A line code violation is defined as a bipolar violation that is not a part of B8ZS encoding
when the control bit EXZ is set low. A line code violation includes both bipolar violations and
excess zeros when EXZ is set high.
Table 69 - Most Significant Bits of the LCV Counter
(Page 4, Address 16H) (T1)
Bit
Name
Functional Description
7 - 0 LCV7 - 0
Least Significant Bits of the LCV Counter. The least significant eight bits of a 16 bit
counter that is incremented once for every line code violation error received.
A line code violation is defined as a bipolar violation that is not a part of B8ZS encoding
when the control bit EXZ is set low. A line code violation includes both bipolar violations and
excess zeros when EXZ is set high.
Table 70 - Least Significant Bits of the LCV Counter
(Page 4, Address 17H) (T1)
Bit
Name
Functional Description
7 - 0 CC15 - 8
CRC-6 Error Counter Bits Fifteen to Eight. These are the most significant eight bits of the
CRC-6 error counter.
Table 71 - CRC-6 Error Counter
(Page 4, Address 18H) (T1)
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Data Sheet
Bit
Name
Functional Description
7 - 0 CC7 - 0
CRC-6 Error Counter Bits Seven to Zero. These are the least significant eight bits of the
CRC-6 error counter.
Table 72 - CRC-6 Error Counter
(Page 4, Address 19H) (T1)
Bit
Name
Functional Description
7
TFSYNI Terminal Frame Synchronization Interrupt. When unmasked this interrupt bit goes high
whenever a change of state of terminal frame synchronization condition exists. Reading this
register clears this bit.
6
MFSYNI Multiframe Synchronization Interrupt. When unmasked this interrupt bit goes high
whenever a change of state of multiframe synchronization condition exists. Reading this
register clears this bit.
5
4
3
BIOMTI Bit Oriented Message Transition Interrupt. When unmasked, this interrupt goes high
whenever a new BIOM arrives or if the current BIOM stops transmission.
AISI
Alarm Indication Signal Interrupt. When unmasked this interrupt bit goes high whenever a
change of state of received all ones condition exists. Reading this register clears this bit.
LOSI
Loss of Signal Interrupt. When unmasked this interrupt bit goes high whenever a change of
state of loss of signal (either analog - signal 40 dB below nominal or digital - excess
consecutive 0’s received) condition exists. Reading this register clears this bit.
2
1
0
SEI
Severely Errored Frame Interrupt. When unmasked this interrupt bit goes high whenever a
sequence of 2 framing errors out of 6 occurs. Reading this register clears this bit.
TxSLPI Transmit SLIP Interrupt. When unmasked this interrupt goes high whenever a controlled
frame slip occurs in the transmit elastic buffer. Reading this register clears this bit.
RxSLPI Receive SLIP Interrupt. When unmasked this interrupt bit goes high whenever a controlled
frame slip occurs in the receive elastic buffer. Reading this register clears this bit.
Table 73 - Interrupt Word Zero
(Page 4, Address 1BH) (T1)
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Data Sheet
Bit
Name
Functional Description
7
FEI
Framing Bit Error Interrupt. When unmasked this interrupt bit goes high whenever an
erroneous framing bit is detected (provided the circuit is in terminal frame sync). Reading this
register clears this bit.
6
5
4
CRCI
YELI
CRC-6 Error Interrupt. When unmasked this interrupt bit goes high whenever a local CRC-6
error occurs. Reading this register clears this bit.
Yellow Alarm Interrupt. When unmasked this interrupt bit goes high upon detection of a
yellow alarm. Reading this register clears this bit.
COFAI Change of Frame Alignment Interrupt. When unmasked this interrupt bit goes high
whenever a change of frame alignment occurs after a reframe. Reading this register clears
this bit.
3
2
LCVI
Line Code Violation Interrupt. When unmasked this interrupt bit goes high whenever a line
code violation (excluding B8ZS encoding) is encountered. Reading this register clears this bit.
PRBSI Psuedo Random Bit Sequence Error Interrupt. When unmasked this interrupt bit goes high
upon detection of an error with a channel selected for PRBS testing. Reading this register
clears this bit.
1
0
PDVI
Pulse Density Violation Interrupt. When unmasked this interrupt bit goes high whenever, in
the absence of B8ZS encoding, a sequence of 16 consecutive zeros is received on the line, or
the incoming pulse density is less than N ones in a time frame of 8(N+1) where N = 1 to 23. In
the case of B8ZS coding, the interrupt is set upon detection of 8 consecutive zeros. Reading
this register clears this bit.
- - -
Unused.
Table 74 - Interrupt Word One
(Page 4, Address 1CH) (T1)
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Data Sheet
Bit
Name
Functional Description
7
FEO
Framing Bit Error Counter Overflow Interrupt. When unmasked this interrupt bit goes
high whenever the framing bit error counter changes from FFH to 00H. Reading this
register clears this bit.
6
5
4
3
2
1
0
CRCO
OOFO
COFAO
LCVO
CRC-6 Error Counter Overflow Interrupt. When unmasked this interrupt bit goes high
whenever the CRC-6 error counter changes from FFH to 00H. Reading this register clears
this bit.
Out Of Frame Counter Overflow Interrupt. When unmasked this interrupt bit goes high
whenever the out of frame counter changes state from changes from FFH to 00H. Reading
this register clears this bit.
Change of Frame Alignment Counter Overflow Interrupt. When unmasked this interrupt
bit goes high whenever the change of frame alignment counter changes from FFH to 00H.
Reading this register clears this bit.
Line Code Violation Counter Overflow Interrupt. When unmasked this interrupt bit goes
high whenever the line code violation counter changes from FFH to 00H. Reading this
register clears this bit.
PRBSO
Psuedo Random Bit Sequence Error Counter Overflow Interrupt. When unmasked this
interrupt bit goes high whenever the PRBS error counter changes from FFH to 00H.
Reading this register clears this bit.
PRBSMFO Psuedo Random Bit Sequence Multiframe Counter Overflow Interrupt. When
unmasked this interrupt bit goes high whenever the multiframe counter attached to the
PRBS error counter overflows. FFH to 00H. 1 - unmasked, 0 - masked.
MFOOFO Multiframes Out Of Sync Overflow Interrupt. When unmasked this interrupt bit goes high
whenever the multiframes out of frame counter changes from FFH to 00H. Reading this
register clears this bit.
Table 75 - Interrupt Word Two
(Page 4, Address 1DH) (T1)
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Data Sheet
Bit
Name
Functional Description
7
HDLC0I HDLC0 Interrupt. Whenever an unmasked HDLC0 interrupt occurs this bit goes high.
Reading this register clears this bit.
6
5
4
HDLC1I HDLC1 Interrupt. Whenever an unmasked HDLC1 interrupt occurs this bit goes high.
Reading this register clears this bit.
HDLC2I HDLC2 Interrupt. Whenever an unmasked HDLC2 interrupt occurs this bit goes high.
Reading this register clears this bit.
LCDI
Loop Code Detected Interrupt. When unmasked this interrupt bit goes high whenever
either the loop up (00001) or loop down (001) code has been detected on the line for a
period of 48 milliseconds. Reading this register clears this bit.
3
1SECI
One Second Status Interrupt. When unmasked this interrupt bit goes high whenever the
1SEC status bit (page 3 address 12H bit 7) goes from low to high. Reading this register
clears this bit.
2
1
5SECI
BIOMI
Five Second Status Interrupt. When unmasked this interrupt bit goes high whenever the 5
SEC status bit goes from low to high. Reading this register clears this bit.
Bit Oriented Message Interrupt. When unmasked this interrupt bit goes high whenever a
pattern 111111110xxxxxx0 has been received on the FDL that is different from the last
message. The new message must persist for 8 out the last 10 message positions to be
accepted as a valid new message. Reading this register clears this bit.
0
SIGI
signaling Interrupt. When unmasked this interrupt bit goes high whenever a change of
state (optionally debounced - see DBEn in the Data Link, signaling Control Word page 1
address 12H) is detected in the signaling bits (AB or ABCD) pattern. Reading this register
clears this bit.
Table 76 - Interrupt Word Three
(Page 4, Address 1EH) (T1)
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Data Sheet
Bit
Name
Functional Description
7
FEOL
Framing Bit Error Counter Overflow Latch. This bit is set when the framing bit
counter overflows. It is cleared after being read.
6
5
4
3
2
1
CRCOL
OOFOL
COFAOL
LCVOL
CRC-6 Error Counter Overflow Latch. This bit is set when the crc error counter
overflows. It is cleared after being read.
Out Of Frame Counter Overflow Latch. This bit is set when the out of frame counter
overflows. It is cleared after being read.
Change of Frame Alignment Counter Overflow Latch. This bit is set when the
change of frame alignment counter overflows. It is cleared after being read.
Line Code Violation Counter Overflow Latch. This bit is set when the line code
violation counter overflows. It is cleared after being read.
PRBSOL
Psuedo Random Bit Sequence Error Counter Overflow Latch. This bit is set when
the PRBS error counter overflows. It is cleared after being read.
PRBSMFOL Psuedo Random Bit Sequence Multiframe Counter Overflow Latch. This bit is set
when the multiframe counter attached to the PRBS error counter overflows. It is cleared
after being read.
0
MFOOFOL
Multiframes Out Of Sync Overflow Latch. This bit is set when the multiframes out of
sync counter overflows. It is cleared after being read.
Table 77 - Overflow Reporting Latch
(Page 4, Address 1FH) (T1)
20.1.5 Per Channel Transmit Signalling (Pages 5 and 6) (T1)
Page 05H, addresses 10000 to 11111, and page 06H addresses 10000 to 10111 contain the Transmit signaling
Control Words for DS1 channels 1 to 16 and 17 to 24 respectively. Table 78 illustrates the mapping between the
addresses of these pages and the DS1 channel numbers. Control of these bits for any one channel is through the
processor or controller port when the Per Time Slot Control bit RPSIG bit is high. Table 79 describes bit allocation
within each of these registers.
Page 5 Address:
0
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
10 11 12 13 14 15
Equivalent DS1
channel
10 11 12 13 14 15 16
Page 6 Address:
0
1
2
3
4
5
6
7
8
x
9
x
10 11 12 13 14 15
Equivalent DS1
channel
17 18 19 20 21 22 23 24
x
x
x
x
x
x
Table 78 - Pages 5 and 6 Address Mapping to DS1 Channels (T1)
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Data Sheet
Bit
Name
Functional Description
7 - 4
3
- - -
Unused.
A(n)
Transmit signaling Bits A for Channel n. Where signaling is enabled, these bits are
transmitted in bit position 8 of the 6th DS1 frame (within the 12 frame superframe structure
for D4 superframes and the 24 frame structure for ESF superframes).
2
1
0
B(n)
C(n)
D(n)
Transmit signaling Bits B for Channel n. Where signaling is enabled, these bits are
transmitted in bit position 8 of the 12th DS1 frame (within the 12 frame superframe structure
for D4 superframes and the 24 frame structure for ESF superframes).
Transmit signaling Bits C for Channel n. Where signaling is enabled, these bits are
transmitted in bit position 8 of the 18th DS1 frame within the 24 frame structure for ESF
superframes. In D4 mode these bits are unused.
Transmit signaling Bits D for Channel n. Where signaling is enabled, these bits are
transmitted in bit position 8 of the 24th DS1 frame within the 24 frame structure for ESF
superframes. In D4 mode these bits are unused.
Table 79 - Transmit Channel Associated Signaling (T1) (Pages 5 and 6)
Serial per channel transmit signaling control through CSTi is selected when the Per Time Slot Control bit RPSIG bit
is low. Table 80 describes the bit allocation within each of the 24 active ST-BUS time slots of CSTi.
Bit
Name
Functional Description
7 - 4
A(n),
B(n)
C(n),
D(n)
Transmit signaling Bits for Channel n. When control bit MSN = 1 and RPSIG = 1 this
nibble is used. For ESF links these 4 bits are transmitted on the associated DS1 channel
(see Table 8) in frames 6, 12, 18 and 24. For D4 links bits A are transmit on the associated
Ds1 channel of frame 6 and bits B are transmit on the associated DS1 channel of frame 12.
For D4 links bits C and D are unused.
3 - 0
A(n),
B(n),
C(n),
D(n)
Transmit signaling Bits for Channel n. When control bit MSN = 0 and RPSIG = 1 this
nibble is used. For ESF links these 4 bits are transmitted on the associated DS1 channel
(see Table 8) in frames 6, 12, 18 and 24. For D4 links bits A are transmit on the associated
Ds1 channel of frame 6 and bits B are transmit on the associated DS1 channel of frame 12.
For D4 links bits C and D are unused.
Table 80 - T1 / Transmit Channels Usage - CSTi
NOTE: This table illustrates bit mapping on the serial input stream - it does not refer to an internal register.
20.2 Per Time Slot Control Words (Pages 7 and 8) (T1)
The control functions described by Table 78 are repeated for each DS1 time slot. Page 7 addresses 10000 to 11111
correspond to DS1 time slot 1 to 16, while page 8 addresses 10000 to 10111 correspond to time slots 17 to 24.
Table 81 illustrates the mapping between the addresses of these pages and the DS1 channel numbers.
Page 7 Address:
0
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
10 11 12 13 14 15
Equivalent DS1
channel
10 11 12 13 14 15 16
Table 81 - Pages 7 and 8 Address Mapping to DS1 Channels
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Data Sheet
Page 8 Address:
0
1
2
3
4
5
6
7
8
x
9
x
10 11 12 13 14 15
Equivalent DS1
channel
17 18 19 20 21 22 23 24
x
x
x
x
x
x
Table 81 - Pages 7 and 8 Address Mapping to DS1 Channels
Functional Description
Bit
Name
7
TXMSG Transmit Message Mode. If high, the data contained in the Transmit Message Register
(address 18H, page 1) is transmitted in the corresponding DS1 time slot. If zero, the data on
DSTi is transmitted on the corresponding DS1 time slot.
6
5
4
3
PCI
Per Channel Inversion. When set high the data for this channel sourced from DSTi is
inverted before being transmit onto the equivalent DS1 channel; the data received from the
incoming DS1 channel is inverted before it emerges from DSTo.
RTSL
LTSL
TTST
Remote Time Slot Loopback. If one, the corresponding DS1 receive time slot is looped to
the corresponding DS1 transmit time slot. This received time slot will also be present on
DSTo. If zero, the loopback is disabled.
Local Time Slot Loopback. If one, the corresponding transmit time slot is looped to the
corresponding receive time slot. This transmit time slot will also be present on the transmit
DS1 stream. If zero, this loopback is disabled.
Transmit Test. If one, a test signal, either digital milliwatt (when control bit ADSEQ is one) or
PRBS (215-1) (ADSEQ is zero), will be transmitted in the corresponding DS1 time slot. More
than one time slot may be activated at once. If zero, the test signal will not be connected to
the corresponding time slot.
2
RTST
Receive Test. If one, the corresponding DSTo timeslot will be used for testing. If control bit
ADEQ is one, a digital milliwatt will be transmitted in the corresponding DSTo channel. If
control bit ADSEQ is zero, the receive channel will be connected to the PRBS detector
(215-1).
1
0
RPSIG
CC
Serial Signaling Enable. If set low, the transmit signaling buffer for the equivalent DS1
channel will be sourced from the ST-BUS channel on CSTi associated with it. If set high the
transmit signaling RAM must be programmed via the microport.
Clear Channel. When set high no robbed bit signaling is inserted in the equivalent transmit
DS1 channel. When set low robbed bit signaling is included in every 6th channel.
Table 82 - Per Time Slot Control Words (Pages 7 and 8) (T1)
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Data Sheet
20.2.1 Per Channel Receive Signaling (T1 and E1 mode) (Pages 9 and 0AH)
Page 09H, addresses 10000 to 11111, and page 1AH addresses 10000 to 10111 contain the Receive signaling
Control Words for DS1 channels 1 to 16 and 17 to 24 respectively. Table 83 illustrates the mapping between the
addresses of these pages and the DS1 channel numbers. Table 84 describes bit allocation within each of these
registers.
Page 9 Address:
0
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
10 11 12 13 14 15
Equivalent DS1
channel
10 11 12 13 14 15 16
Page A Address:
0
1
2
3
4
5
6
7
8
x
9
x
10 11 12 13 14 15
Equivalent DS1
channel
17 18 19 20 21 22 23 24
x
x
x
x
x
x
Table 83 - Pages 9 and A Address Mapping to DS1 Channels (T1)
Bit
Name
Functional Description
7 - 4
3
- - -
Unused.
A(n)
Receive signaling Bits A for Channel n. These bits are extracted from bit position 8 of
every channel in received frame 6 (within the 12 frame superframe structure for D4
superframes and the 24 frame structure for ESF superframes). The bits may be debounced
for 6 to 9 milliseconds where control bit DBNCE is set high.
2
1
0
B(n)
C(n)
D(n)
Receive signaling Bits B for Channel n. These bits are extracted from bit position 8 of
every channel in received frame 12 (within the 12 frame superframe structure for D4
superframes and the 24 frame structure for ESF superframes). The bits may be debounced
for 6 to 9 milliseconds where control bit DBNCE is set high.
Receive signaling Bits C for Channel n. These bits are extracted from bit position 8 of
every channel in received frame 18 within the 24 frame structure for ESF superframes. The
bits reported may be debounced for 6 to 9 milliseconds where control bit DBNCE is set high.
In D4 mode these bits are unused.
Receive signaling Bits D for Channel n. These bits are extracted from bit position 8 of
every channel in received frame 24 within the 24 frame structure for ESF superframes. The
bits reported may be debounced for 6 to 9 milliseconds where control bit DBNCE is set high.
In D4 mode these bits are unused.
Table 84 - Receive Channel Associated Signaling (Pages 9 and A) (T1)
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Data Sheet
20.3 E1 Mode
20.3.1 Master Control 1 (Page 01H) (E1)
Address
Register
Function
(A4A3A2A1A0)
10H (Table 86)
Mode Selection Control Word
ASEL, CRCM, AUTC, ARAI, AUTY, CSYN,
REFRM, MFRF
11H (Table 87)
12H (Table 88)
13H (Table 89)
14H (Table 90)
15H (Table 91)
Transmit Alarm Control Word
TS0 Control Word
TE, TAIS16, TxAO, Einv
EXZ, SaBorNi, RxTRSP, TxTRSP, TIU1,TIU0
TMA1-4,X1,Y, X2, X3
Transmit Multiframe Alignment Signal
Interrupt and signaling Control Word
Coding and Loopback Control Word
DSToEn, CSToEn, TxCCS, DBNCE, MSN
RxHDB3, MLBK, TxHDB3, DLBK, RLBK,
SLBK, PLBK
16H (Table 92)
17H (Table 93)
18H (Table 94)
19H (Table 95)
Non Frame Alignment Control Word
Multiframe and Data Link Selection
Transmit Message Word
TALM, TNU4-8
MFSEL, NBTB, Sa4-Sa8
TXM7-0
Error Insertion Word
BPVE, CRCE, FASE, NFSE, LOSE, PERR,
L32Z, LOS/LOF
1AH (Table 96) Signaling Control Word
1BH (Table 97) Interrupt Mask Word Zero
RST, SPND, INTA, CNTCLR, SAMPLE, OOFP
SYNIM, MFSYIM, CSYNIM, AISIM, LOSIM,
CEFIM, YMI, SLPIM
1CH (Table 98) Interrupt Mask Word One
1DH (Table 99) Interrupt Mask Word Two
1EH (Table 100) Interrupt Mask Word Three
1FH (Table 101) LIU Receiver Word
FERIM, CRCIM, EBIM, AIS16IM, LCVIM,
PRBSIM, AUXPIM & RAIM
FEOM, CRCOM, EOM, LCVOM, PRBSOM,
PRBSMFOM, SaIM
HDLC0IM, HDLC1IM, HDLC2IM, JAIM,
1SECIM, 5SECIM, RCRIM, SIGIM
NRZ, RxA1-0, RxEQ2-0
Table 85 - Master Control 1 (Page 1) (E1)
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Data Sheet
Bit
Name
Functional Description
7
ASEL
AIS Select. This bit selects the criteria on which the detection of a valid Alarm Indication
Signal (AIS) is based. If zero, the criteria is less than three zeros in a two frame period (512
bits). If one, the criteria is less than three zeros in each of two consecutive double-frame
periods (512 bits per double frame).
6
CRCM
CRC-4 Modification. If one activates the CRC-4 remainder modification function when the
device is in transparent mode. The received CRC-4 remainder is modified to reflect only the
changes in the transmit DL. If zero, time slot zero data from DSTi will not be modified in
transparent mode.
5
4
AUTC
ARAI
Automatic CRC-interworking. If zero, automatic CRC-interworking is activated. If one it is
deactivated. See Framing Algorithm for a detailed description.
Automatic Remote Alarm Indication. if zero, the Remote Alarm Indication bit (the
A bit) will function automatically. That is, RAI=1 when basic synchronization has
been acquired. And, RAI=0 when basic synchronization has not been acquired. if
one, the remote alarm indication bit is controlled through the TALM bit of the transmit
Non-Frame Alignment Control Word.
3
2
AUTY
CSYN
Automatic Y-Bit Operation. If zero, the Y-bit of the transmit multiframe alignment signal will
report the multiframe alignment status to the far end i.e., zero - multiframe alignment
acquired, one - lost. If one, the Y-bit is under the manual control of the Transmit Multiframe
Alignment Control Word.
CRC-4 Synchronization. If zero, basic CRC-4 synchronization processing is activated, and
the TIU0 Bit and the TIU1 bit programming will be overwritten. If one, CRC-4 synchronization
is disabled, the first bits of channel 0 are used as international use bits and are programmed
by the TIU0 and TIU1.
1
0
REFRM
MFRF
Reframe. If one for at least one frame, and then cleared, the device will initiate a search for a
new basic frame position. Reframing function is activated on the one to zero transition of the
REFRM bit.
Multiframe Reframe. If one, for at least one frame, and then cleared the 3VJET will initiate a
search for a new signaling multiframe position. Reframing function is activated on the one to
zero transition of the MFRM bit.
Table 86 - Mode Selection Control Word (E1)
(Page 1, Address 10H)
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Zarlink Semiconductor Inc.
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Data Sheet
Bit
Name
Functional Description
Reserved. Must be kept at 0 for normal operation.
7
6
- -
TE
Transmit E bits. When zero and CRC-4 synchronization is achieved, the E-bits transmit the
received CRC-4 comparison results to the distant end of the link, as per G.703. That is, when
zero and CRC-4 synchronization is lost, the transmit E-bits will be zero. If one, and CRC-4
synchronization is lost the transmit E-bits will be one.
5
4
3
TAIS16 Transmit AIS Time Slot 16. If one, an all ones signal is transmitted in time slot 16. If zero,
time slot functions normally.
TxAO
Einv
Transmit All Ones. When low, this control bit forces a framed or unframed (depending on
the state of Transmit Alarm Control bit 0) all ones to be transmit at TTIP and TRING.
Ebit Error Inversion. When zero, received Ebits set to zero are counted in the Ebit error
counter and interrupt generator. When one, Ebits set to one are counted in the Ebit error
counter and interrupt generator.
2-0
- - -
Unused.
Table 87 - Transmit Alarm Control Word (E1)
(Page 1, Address 11H)
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Data Sheet
Bit
Name
Functional Description
7
6
5
- - -
- - -
Unused.
Unused.
EXZ
Excess Zeros. Setting this bit causes each occurrence of received excess zeros to
increment the Line Code Violation Counter. Excess zeros are defined as 4 or more
successive zeros for HDB3 encoded data, or 16 or more successive zeros for non-HDB3
encoded data.
4
3
SaBorNi Sa Bit or Nibble. Set this bit to determine the criteria for interrupts due to transitions of Sa
bits. If set to one, a change of state of any Sa bit is the criteria. If set to zero, a change of
state of an Sa nibble is the criteria. Note that the selected event can only trigger an interrupt
if the interrupt mask bit SaIM is set high in the Interrupt Mask Word Two - page 1 address
1DH bit 0.
RxTRSP Receive Transparent Mode. When this bit is set to one, the framing function is disabled on
the receive side. Data coming from the receive line passes through the slip buffer and drives
DSTo with an arbitrary alignment. When zero, the receive framing function operates
normally.
2
1
TxTRSP Transmit Transparent Mode. If one, the MT9076 is in transmit transparent mode. No
framing or signaling is imposed on the data transmit from DSTi onto the line. If zero, it is in
termination mode.
TIU1
Transmit International Use One. When CRC-4 operation is disabled (CSYN=1), this bit is
transmit on the PCM 30 2048 kbit/sec. link in bit position one of time-slot zero of
non-frame-alignment frames. It is reserved for international use and should normally be kept
at one. If CRC processing is used, i.e., CSYN =0, this bit is ignored.
0
TIU0
Transmit International Use Zero. When CRC-4 operation is disabled (CSYN=1), this bit is
transmit on the PCM 30 2048 kbit/sec. link in bit position one of time-slot zero of
frame-alignment frames. It is reserved for international use and should normally be kept at
one. If CRC processing is used, i.e., CSYN =0, this bit is ignored.
Table 88 - TS0 Control Word (E1)
(Page 1, Address 12H)
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Zarlink Semiconductor Inc.
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Data Sheet
Bit
Name
Functional Description
7-4
TMA1-4 Transmit Multiframe Alignment Bits One to Four. These bits are transmitted on the PCM
30 2048 kbit/sec. link in bit positions one to four of time slot 16 of frame zero of every
signaling multiframe. These bits are used by the far end to identify specific frames of a
signaling multiframe. TMA1-4 = 0000 for normal operation.
3
2
X1
This bit is transmitted on the PCM 30 2048 kbit/sec. link in bit position five of time slot 16 of
frame zero of every multiframe. X1 is normally set to one.
Y
This bit is transmitted on the PCM 30 2048 kbit/sec. link in bit position six of time slot 16 of
frame zero of every multiframe. It is used to indicate the loss of multiframe alignment to the
remote end of the link. If one - loss of multiframe alignment; if zero - multiframe alignment
acquired. This bit is ignored when AUTY is zero (page 01H, address 11H).
1, 0
X2, X3 These bits are transmitted on the PCM 30 2048 kbit/sec. link in bit positions seven and eight
respectively, of time slot 16 of frame zero of every multiframe. X2 and X3 are normally set to
one.
Table 89 - Transmit Multiframe Alignment Signal (E1)
(Page 1, Address 13H)
Bit
Name
Functional Description
7
6
5
DSToEn DSTo Enable. If zero pin DSTo is tristate. If set the pin DSTo is enabled.
CSToEn CSTo Enable. If zero pin CSTo is tristate. If set the pin CSTo is enabled.
TxCCS Transmit Common Channel signaling. If one, the transmit channel 16 of the device is in
common channel signaling (CCS) mode. If zero, it is in Channel Associated signaling (CAS)
mode, data for channel 16 is sourced from the internal transmission ABCD register.
4
3
DBNCE Debounce Select. This bit selects the debounce period (1 for 14 msec.; 0 for no debounce).
Note: there may be as much as 2 msec. added to this duration because the state change of
the signaling equipment is not synchronous with the PCM 30 signaling multiframe.
MSN
Most Significant signaling Nibble. If one, the CSTo and CSTi channel associated signaling
nibbles will be valid in the most significant portion of each ST-BUS time slot. If zero, the
CSTo and CSTi channel associated signaling nibbles will be valid in the least significant
portion of each ST-BUS time slot.
2,1,0
- - -
Unused.
Table 90 - Interrupt and Signaling Control Word (E1)
(Page 1, Address 14H)
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Data Sheet
Bit
Name
Functional Description
7
RxHDB3 High Density Bipolar 3 Encoding. If one, HDB3 encoding is enabled in the receive
direction. If zero, AMI signal without HDB3 encoding is received.
6
5
MLBK
Metallic Loopback. If one, then the external RRTIP and RRING signals are isolated from the
receiver, and TTIP and TRING are internally connected to the receiver analog input instead. If
zero, metallic loopback is disabled.
TxHDB3 High Density Bipolar 3 Encoding. If one, HDB3 encoding is enabled in the transmit
direction. If zero, AMI signal without HDB3 encoding is transmitted. HDB3 is always decoded
in the receive direction.
4
3
- - -
Unused.
DLBK
Digital Loopback. If one, then the digital stream to the transmit LIU is looped back in place of
the digital output of the receive LIU. Data coming out of DSTo will be a delayed version of
DSTi. If zero, this feature is disabled.
2
1
0
RLBK
SLBK
PLBK
Remote Loopback. If one, then all bipolar data received on RRTIP/RRING are directly routed
to TTIP/TRING on the PCM 30 side of the MT9076. If zero, then this feature is disabled.
ST-BUS Loopback. If one, then all time slots of DSTi are connected to DSTo on the ST-BUS
side of the MT9076. If zero, then this feature is disabled. See Loopbacks section.
Payload Loopback. If one, then all time slots received on RTIP/RRING are connected to
TTIP/TRING on the ST-BUS side of the MT9076 (this excludes time slot zero). If zero, then
this feature is disabled.
Table 91 - Coding and Loopback Control Word (E1)
(Page 1, Address 15H)
Bit
Name
Functional Description
7 - 6
5
- - -
Unused.
TALM
Transmit Remote Alarm. This bit is transmitted on the PCM 30 2048 kbit/sec. link in bit
position three (A bit) of time slot zero of NFAS frames. It is used to signal an alarm to the
remote end of the PCM 30 link (one - alarm, zero - normal). This control bit is ignored when
ARAI is zero (page 01H, address 10H).
4-0
TNU4-8 Transmit National Use Four to Eight (Sa4 - Sa8). These bits are transmitted on the PCM
30 2048 kbit/sec. link in bit positions four to eight of time slot zero of the NFA frame, if
selected by Sa4 - Sa8 control bits of the DL selection word (page 01H, address 10H).
Table 92 - Non Frame Alignment Control Word (E1)
(Page 1, Address 16H)
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Data Sheet
Bit
Name
Functional Description
7
6
- - -
Unused.
MFSEL Multiframe Select. This bit determines which receive multiframe signal (CRC-4 or signaling)
the RxMF (pin 42 in PLCC, 23 in MQFP) signal is aligned with. If zero, RxMF is aligned with
the receive signaling multiframe. If one, RxMF is aligned with the receive CRC-4 multiframe.
5
NBTB
National Bit Transmit Buffer. If one, the transmit NFAS signal originates from the transmit
national bit buffer page 0EH; if zero, the transmit NFAS signal originates from the TNU4-8 bits
of page 1 address 16H.
4-0
Sa4-Sa8 National Bit Data Link Select A one selects the corresponding Sa bits of the NFA signal for
4, 8, 12, 16 or 20 kbits/sec. data link channel. Data link (DL) selection will function in
termination mode only; in transmit transparent mode Sa4 is automatically selected - see
TxTRSP control bit of page 01H, address 11H. If zero, the corresponding bits of transmit
non-frame alignment signal are programmed by the Non-Frame Alignment Control Word
(page 01H, address 12H).
Table 93 - Multiframe and Data Link Selection (E1)
(Page 1, Address 17H)
Bit
Name
Functional Description
7-0
TxM7-0 Transmit Message Bits 7 - 0. The contents of this register are transmit into those outgoing
DS1 channels selected by the Per Time Slot Control registers.
Table 94 - Transmit Message Word (E1)
(Page 1, Address 18H)
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Data Sheet
Bit
Name
Functional Description
7
BPVE
Bipolar Violation Error Insertion. A zero to one transition of this bit inserts a single
bipolar violation error into the transmit PCM 30 data. A one, zero or one to zero transition
has no function.
6
5
CRCE
FASE
CRC-4 Error Insertion. A zero to one transition of this bit inserts a single CRC-4 error into
the transmit PCM 30 data. A one, zero, or one to zero transition has no function.
Frame Alignment Signal Error Insertion. A zero to one transition of this bit inserts a
single error into the time slot zero frame alignment signal of the transmit PCM 30 data. A
one, zero, or one to zero transition has no function.
4
3
NFSE
LOSE
Non-frame Alignment Signal Error Insertion. A zero to one transition of this bit inserts a
single error into bit two of the time slot zero non-frame alignment signal of the transmit
PCM 30 data. A one, zero, or one to zero transition has no function.
Loss of Signal Error Insertion. If one, the MT9076 transmits an all zeros signal (no
pulses) in every PCM 30 time slot. When HDB3 encoding is activated no violations are
transmitted. If zero, data is transmitted normally.
2
1
0
PERR
L32Z
Payload Error Insertion. A zero to one transition of this bit inserts a single error in the
transmit payload. A one, zero, or one to zero transition has no function.
Digital Loss of Signal Selection. If one, the threshold for digital loss of signal is 32
successive zeros. If zero, the threshold is set to 192 successive zeros.
LOS/LOF Loss of Signal or Loss of Frame Selection. If one, pin LOS (pin 61 in PLCC, 57 in
MQFP) will go high when a loss of signal state exits. A loss of signal is defined as either
receipt of a signal attenuated below the analog loss of signal threshold (selectable as
20 dB or 40 dB below nominal) or receipt of 256 consecutive 0’s. If low, pin LOS will go
high when either a loss of signal or a loss of basic frame alignment state exits (bit SYNC on
page 03H address 10H is zero).
Table 95 - Error Insertion Word (E1)
(Page 1, Address 19H)
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Data Sheet
Bit
Name
Functional Description
7
RST
Reset. When this bit is changed from zero to one the device will reset to its default mode.
See the Reset Operation section for the default settings.
6
SPND
INTA
Suspend Interrupts. If one, the IRQ output (pin 12 in PLCC, 85 in MQFP) will be in a
high-impedance state and all interrupts will be ignored. If zero, the IRQ output will function
normally.
5
4
3
Interrupt Acknowledge. A zero-to-one or one-to-zero transition will clear any pending
interrupt and make IRQ high.
CNTCLR Counter Clear. If one, all status counters are cleared and held low. Zero for normal
operation.
SAMPLE One Second Sample. Setting this bit causes the error counters (change of frame alignment,
loss of frame alignment, lcv errors, crc errors, severely errored frame events and multiframes
out of sync) to be updated on one second intervals coincident with the one second timer
(status page 3 address 12H bit 7).
2
OOFP
Out of Frame Pause. If set high, this bit will suspend operation of the Line Code VIolation
Counter during an out - of - frame condition; upon achieving terminal frame synchronization
the counter will resume normal operation. If set low, the Line Code Violation counter will
continue to count errors even if terminal frame synchronization is lost.
1
0
- -
Reserved. Set low for normal operation.
D20
Double 20. Set low for normal operation. Set high to double clock speed in the HDLC to
speed up memory accesses from 160 ns between consecutive reads/writes to 80 ns
between consecutive reads/writes.
Table 96 - Signaling Control Word (E1)
(Page 1, Address 1AH)
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Data Sheet
Bit
Name
Functional Description
7
SYNIM
Synchronization Interrupt Mask. When unmasked (SYNI = 1) an interrupt is initiated
whenever a change of state of loss of basic frame synchronization condition exists. If 1-
unmasked, 0 - masked.
6
5
MFSYIM Multiframe Synchronization Interrupt Mask. When unmasked (MFSYI = 1), an interrupt
is initiated whenever a change of state of multiframe synchronization exists. If 1- unmasked,
0 - masked.
CSYNIM CRC-4 Multiframe Synchronization Interrupt Mask. When unmasked (CSYNI = 1), an
interrupt is initiated whenever a change of state of CRC-4 multiframe synchronization exists.
If 1- unmasked, 0 - masked.
4
3
AISIM
Alarm Indication Signal Interrupt Mask. When unmasked (AISI = 1) a change of state of
received AIS will initiate an interrupt. If 1- unmasked, 0 - masked.
LOSIM
Loss of Signal Interrupt Mask. When unmasked this interrupt bit goes high whenever a
change of state of loss of signal (either analog - received signal 20 or 40 dB below nominal
or digital - 256 consecutive 0’s received) condition exists. If 1- unmasked, 0 - masked.
2
1
0
CEFIM
YIM
Consecutively Errored FASs Interrupt Mask. When unmasked an interrupt is initiated
when two consecutive errored frame alignment signals are received. If 1 - unmasked, 0 -
masked.
Remote signaling Multiframe Alarm Interrupt Mask. When unmasked (YI = 1), an
interrupt is initiated whenever a change of state of when a remote signaling multiframe
alarm signal is received. If 1- unmasked, 0 - masked.
SLPIM
SLIP Interrupt Mask. When unmasked (SLPI = 1), an interrupt is initiated when a controlled
frame slip occurs. If 1- unmasked, 0 - masked.
Table 97 - Interrupt Mask Word Zero (E1)
(Page 1, Address 1BH)
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Data Sheet
Bit
Name
Functional Description
7
FERIM Frame Error Interrupt Mask. When unmasked (FERI = 1), an interrupt is initiated when an
error in the frame alignment signal occurs. If 1- unmasked, 0 - masked.
6
5
4
3
2
1
0
CRCIM CRC-4 Error Interrupt Mask. When unmasked an interrupt is initiated when a local CRC-4
error occurs. If 1 - unmasked, 0 - masked.
EBIM
Receive E-bit Interrupt Mask. When unmasked an interrupt is initiated when a receive E-bit
indicates a remote CRC-4 error. If 1 - unmasked, 0 - masked.
AIS16IM Channel 16 Alarm Indication Signal Interrupt Mask. When unmasked (AIS16I = 1), a
received AIS16 will initiate an interrupt. If 1- unmasked, 0 - masked.
LCVIM Line Code Violation Interrupt Mask. When unmasked an interrupt is initiated when a line
code violation error occurs. If 1 - unmasked, 0 - masked.
PRBSIM PRBS Interrupt Mask. When unmasked (PRBSI = 1), an interrupt is initiated on a single
PRBS detection error. If 1- unmasked, 0 - masked.
AUXPIM Auxiliary Pattern Interrupt Mask. When unmasked (AUXPI = 1), an interrupt is initiated
when the AUXP status bit of page 03H, address 15H goes high. If 1- unmasked, 0 - masked.
RAIIM
Remote Alarm Indication Interrupt Mask. When unmasked (RAII = 1) a received RAI will
initiate an interrupt. If 1- unmasked, 0 - masked.
Table 98 - Interrupt Mask Word One (E1)
(Page 1, Address 1CH)
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Data Sheet
Bit
Name
Functional Description
7
FEOM
Frame Alignment Signal Error Counter Overflow Interrupt Mask. When unmasked an
interrupt is initiated when the frame alignment signal error counter overflows. If 1 -
unmasked, 0 - masked.
6
CRCOIM
CRC-4 Error Counter Overflow Interrupt Mask. When unmasked an interrupt is initiated
when the CRC-4 error counter overflows. If 1 - unmasked, 0 - masked.
5
4
- - -
Unused.
EBOIM
Receive E-bit Counter Overflow Interrupt Mask. When unmasked an interrupt is
initiated when the E-bit error counter overflows. If 1 - unmasked, 0 - masked.
3
2
1
0
LCVCOM Line Code Violation Counter Overflow Interrupt Mask. When unmasked (LCVO = 1),
an interrupt is initiated when the line code violation error counter changes form FFFFH to
0H. If 1- unmasked 0 - masked.
PRBSOM PRBS Counter Overflow Interrupt Mask. When unmasked (PRBSO = 1), an interrupt is
initiated on overflow of PRBS counter (page 04H, address 10H) from FFH to 0H. If 1-
unmasked 0 - masked.
PRBSMFOM PRBS MultiFrame Counter Overflow Interrupt Mask. When unmasked an interrupt will
be generated whenever the multiframe counter attached to the PRBS error counter
overflows. If 1- unmasked 0 - masked.
SaIM
Sa Bits Interrupt Masks. When unmasked an interrupt will be triggered by either a
change of state of any of the received Sa bits Sa5, Sa6, Sa7 or Sa8 (SaBorNi = 1) or a
change of state of any of the received Sa nibbles (SaBorNi = 0). The control bit SaBorNi is
located in page 1 address 12H bit 4. If 1- unmasked 0 - masked.
Table 99 - Interrupt Mask Word Two (E1) (Page 1, Address 1DH)
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Data Sheet
Bit
Name
Functional Description
7
HDLC0IM HDLC0 Interrupt Mask. When unmasked an interrupt is triggered by an unmasked event in
HDLC0. If 1 - unmasked, 0 - masked.
6
5
4
HDLC1IM HDLC1 Interrupt Mask. When unmasked an interrupt is triggered by an unmasked event in
HDLC1. If 1 - unmasked, 0 - masked.
HDLC2IM HDLC2 Interrupt Mask. When unmasked an interrupt is triggered by an unmasked event in
HDLC2. If 1 - unmasked, 0 - masked.
JAIM
Jitter Attenuation Interrupt Mask. When unmasked, an interrupt will be initiated when the
jitter attenuator FIFO comes within four bytes of an overflow or underflow condition. If 1 -
unmasked, 0 - masked.
3
2
1
0
1SECIM One Second Status Interrupt Mask. When unmasked (1SECI = 1), an interrupt is initiated
when the 1SEC status bit changes from zero to one. If 1- unmasked, 0 - masked.
5SECIM Five Second Status Interrupt Mask. When unmasked (5SECI = 1), an interrupt is initiated
when the 5SECI status bit changes from zero to one. If 1- unmasked, 0 - masked.
RCRIM
SIGIM
RCRI Interrupt Mask. Whenever an unmasked (RCRI=1), an interrupt is initiated when RCR
(remote alarm & CRC-4 error) status bit changes from zero to one. If 1- unmasked, 0 - masked.
signaling (CAS) Interrupt Mask. When unmasked and any of the receive ABCD bits of any
channel changes state an interrupt is initiated. If 1 - unmasked, 0 - masked.
Table 100 - Interrupt Mask Word Three (E1) (Page 1, Address 1EH)
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Data Sheet
Bit
Name
Functional Description
7
NRZ
NRZ Format Selection. Only used in the digital framer only mode (LIU is
disabled). A one sets the MT9076 to accept a unipolar NRZ format input
stream on RxA as the line input, and to transmit a unipolar NRZ format
stream on TxB. A zero causes the MT9076 to accept a complementary pair
of dual rail inputs on RxA/RxA and to transmit a complementary pair of dual
rail outputs on TxA/TxB.
6 - 5
4-3
- - -
Reserved. Set these bits low for normal operation.
RxA1-0
Automatic Receive Equalizer Control. These bits should be programmed
according to the table below:
00
11
Equalization will be activated using the control bits RxEQ2-0
The receive equalizer is turned on and will compensate for loop
length automatically. The control bits RxEQ2-0 will be ignored.
01, 10 Reserved for factory purposes.
2-0
RxEQ2-0
Receive Equalization Select. Setting these pins forces a level of
equalization of the incoming line data.
RES2 RES1 RES0 Receive Equalization
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
none
8 dB
16 dB
24 dB
32 dB
40 dB
48 dB
reserved
These settings have no effect if either of RxA1 and RxA0 are set to one.
Table 101 - LIU Receive Word (E1) (Page 1, Address 1FH)
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Data Sheet
20.4 Master Control 2 (Page-2)
20.4.1 Master Control 2 (Page 02H) (E1)
Address
Register
Names
(A4A3A2A1A0)
10H (Table 103) Configuration Control Word
11H (Table 104) LIU Tx Word
T1/E1, TxEN, LIUEn, ELOS, Tx8KEN, ADSEQ
WR, Pk2, Pk1, CPL, TxLB2-0
12H
Reserved
Set all bits to zero for normal operation.
13H (Table 105) Jitter Attenuator Control Word
JFC, JFD2-JFD0, JACL
14H
15H
Reserved
Reserved
Set all bits to zero for normal operation.
Set all bits to zero for normal operation.
16H (Table 106) Equalizer High Threshold
17H (Table 107) Equalizer Low Threshold
18H (Table 108) Serial Bit Rate
EHT7-0
ELT7-0
IMA,8Men,8MTS1-0
En, SaSEL, CH4-0
En, CH4-0
En, CH4-0
CP6-0
19H (Table 109) HDCL0 Select
1AH (Table 110) HDCL1 Select
1BH (Table 111) HDLC2 Select
1CH (Table 112) Custom Pulse Word 1
1DH (Table 113) Custom Pulse Word 2
1EH (Table 114) Custom Pulse Word 3
1FH (Table 115) Custom Pulse Word 4
CP6-0
CP6-0
CP6-0
Table 102 - Master Control 2 (Page 02H) (E1)
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Zarlink Semiconductor Inc.
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Data Sheet
Bit
Name
Functional Description
7
6
5
T1/E1
- -
E1 mode selection. when this bit is one, the device is in E1 mode.
Reserved. Must be kept at 0 for normal operation.
TxEN
Transmit Enable. Setting this bit low turns off the TTIP and TRING output line drivers.
Setting this bit high enables them.
4
LIUEn
LIU Enable.Setting this bit low enables the internal LIU front-end. Setting this pin high
disables the LIU. Digital inputs RXA and RXB are sampled by the rising edge of E2.0i (Exclk)
to strobe in the received line data. Digital transmit data is clocked out of pins TXA and TXB
with the rising edge of C2.0o
3
2
ELOS
ELOS Enable. Set this bit low to set the analog loss of signal threshold to 40 dB below
nominal. Set this bit high to set the analog loss of signal threshold to 20 dB below nominal.
Tx8KEN
Transmit 8 KHz Enable. If one, the pin RxMF/TxFP transmits a positive 8 KHz frame pulse
synchronous with the serial data stream transmit on TXA/TXB. If zero, the pin RxMF/TxFP
transmits a negative frame pulse synchronous with the multiframe boundary of data coming
out of DSTo.
1
0
ADSEQ
- -
Digital Milliwatt or Digital Test Sequence. If one, the A-law digital milliwatt analog test
sequence will be selected by the Per Time Slot Control bits TTST and RTST.If zero, a PRBS
generator / detector will be connected to channels with TTST, RRST respectively
Reserved. Set this bit low for normal operation.
Table 103 - Configuration Control Word
(Page 2, Address 10H) (E1)
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Data Sheet
Bit
Name
Functional Description
7
WR
Winding Ratio. Set this pin low if a 1:2.4 transformer is used on the transmit side. Set this pin
high if a 1:2 transformer is used.
6-4
3
- -
Reserved. Must be kept at 0 for normal operation.
CPL
Custom Pulse Level. Setting this bit low enables the internal ROM values in generating the
transmit pulses. The ROM is coded for different line terminations or build out, as specified in the
LIU Control word. Setting this pin high disables the pre-programmed pulse templates. Each of
the 4 phases that generate a mark derive their D/A coefficients from the values programmed in
the CPW registers.
2 - 0 TX2-0 Transmit pulse amplitude. Select the TX2 –TX0 bits according to the line type, value of
termination resistors (RT), and transformer turns ratio used.
TX2 TX1 TX0
Line Impedance (ohms)
RT(ohms) Transformer Ratio WR (bit 7)
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
120
120
120
75
-
75
75
75
0
6.8
6.8
5.1
-
6
6
5.1
1:2.4
1:2
1:2.4
1:2.4
-
1:2
1:2
1:2.4
0
0
0
0
-
1
1
0
After reset, these bits are zero.
Table 104 - LIU Tx Word
(Page 2, Address 11H) (E1)
117
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Bit
Name
Functional Description
7
6
- - -
Unused.
JFC
Jitter Attenuator FIFO Centre. When this bit is toggled the read pointer on the jitter
attenuator shall be centered. During this centering the jitter on the JA outputs is increased
by 0.0625 U.I.
5 - 3 JFD2-JFD0 Jitter Attenuator FIFO Depth Control Bits. These bits determine the depths of the jitter
attenuator FIFO as shown below:
JFD2
JFD1
JFD0
Depth
16
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
32
48
64
80
96
112
128
2
JACL
- - -
Jitter Attenuator FIFO Clear Bit. If one, the Jitter Attenuator, its FIFO and status are reset.
The status registers will identify the FIFO as being empty. However, the actual bit values of
the data in the JA FIFO will not be reset.
1 - 0
Unused.
Table 105 - Jitter Attenuation Control Word
(Page 2, Address 13H) (E1)
Bit
Name
Functional Description
7-0
EHT7-0
Equalizer High Threshold. These bits set the highest possible binary count tolerable
coming out of the equalized signal peak detector before a lower level of equalization is
selected. This register is only used when A/D based automatic equalization is selected using
the Rx LIU Control Word. The recommended value to program is 10111011.
Table 106 - Equalizer High Threshold
(Page 2, Address 16H) (E1)
Bit
Name
Functional Description
7-0
ELT7-0
Equalizer Low Threshold. These bits set the lowest possible binary count tolerable coming
out of the equalized signal peak detector before a higher level of equalization is selected.
This register is only used when A/D based automatic equalization is selected using the Rx
LIU Control Word. The recommended value to program is 00110000.
Table 107 - Equalizer Low Threshold
(Page 2, Address 17H) (E1)
118
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Bit
Name
Functional Description
Reserved. Must be kept at 0 for normal operation.
7 - 6
5
- -
IMA
Inverse Mux Mode. Setting this bit high the I/O ports to allow for easy connection to the
Zarlink MT90220. DSTi becomes a serial 2.048 data stream. C4b becomes a 2.048 MHz
clock that clocks DSTi in on the falling edge. RXFP becomes a positive framing pulse that is
high for the first bit of the serial E1 stream coming from the pin DSTo. The data from DSTo is
clocked out on the rising edge of Exclk. Set this pin low for all other applications.
4 - 3
2
- -
Reserved. Must be kept at 0 for normal operation.
8Men
8 Mb/s Bit Rate Select. Setting this bit low enables a serial bit rate on DSTi, CSTi and
DSTo,CSTo of 2.048 Mb/s. Setting this bit high enables a gapped serial bit rate of 8.192 Mb/s
on DSTi, CSTi, DSTo and CSTo.
1 - 0 8MTS1- 0 8 Mb/s Time Slot Select. These two bits select the active timeslots on the serial 8.192 Mb/s
channels. During the active timeslots incoming serial data on DSTi and CSTi is clocked into
the device, and data is clocked out onto DSTo and CSTo. During inactive timeslots DSTo and
CSTo are tristate. For all selections every fourth 8 Mb/s timeslot is active.
The timeslot selection is as follows:
8MTS1 8MST0
Active timeslots
0
0
1
1
0
1
0
1
0,4,8,12,16,20,24,28,32,36,40,44,48,52,56,60,64,68,72,76,80,84,88,92
96,100,104,108,112,116,120,124
1,5,9,13,17,21,25,29,33,37,41,45,49,53,57,61,65,69,73,77,81,85,89,93
97,101,105,109,113,117,121,125
2 ,6,10,14,18,22,26,30,34,38,42,46,50,54,58,62,66,70,74,78,82,86, 90,
94, 98,102,106,110,114,118,122,126
3,7,11,15,19,23,27,31,35,39,43,47,51,55,59,63,67,71,75,79,83,
87,91,95,99,103,107,111,115,119,123,127
Table 108 - Serial Bit Rate
(Page 2, Address 18H) (E1)
Bit
Name
Functional Description
7
En
Enable. Set high to attach the HDLC0 controller to the channel specified below. Set
low to disconnect the HDLC0.
6
SaSEL
Sa Bits Select. Set this bit to 0 to attach HDLC0 to the Sa bits. Set this bit to 1 to
attach HDLC0 to a payload timeslot.
5
- -
Reserved. Must be kept at 0 for normal operation.
4-0
CH4-0
Channel 4-0. This 5 bit number specifies the channel time HDLC0 will be attached
to if enabled. Channel 0 is the first channel in the frame. Channel 31 is the last
channel in an E1 frame. If enabled in a channel, HDLC data will be substituted for
data from DSTi on the transmit side. Receive data is extracted from the incoming
line data before the elastic buffer.
Table 109 - HDLC0 Select
(Page 2, Address 19H) (E1)
119
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Bit
Name
Functional Description
7
En
Enable. Set high to attach the HDLC1 controller to the channel specified below. Set
low to disconnect the HDLC1.
6-5
4-0
- -
Reserved. Must be kept at 0 for normal operation.
CH4-0
Channel 4-0. This 5 bit number specifies the channel time HDLC1 will be attached
to if enabled. Channel 0 is the first channel in the frame. Channel 31 is the last
channel in an E1 frame. If enabled in a channel, HDLC data will be substituted for
data from DSTi on the transmit side. Receive data is extracted from the incoming
line data before the elastic buffer. Channel 0 selection is unavailable to this
controller.
Table 110 - HDLC1 Select
(Page 2, Address 1AH) (E1)
Bit
Name
Functional Description
7
En
Enable. Set high to attach the HDLC2 controller to the channel specified below. Set low to
disconnect the HDLC2.
6-5
4-0
- -
Reserved. Must be kept at 0 for normal operation.
CH4-0
Channel 4-0. This 5 bit number specifies the channel time HDLC2 will be attached to if
enabled. Channel 0 is the first channel in the frame. Channel 31 is the last channel in an E1
frame. If enabled in a channel, HDLC data will be substituted for data from DSTi on the
transmit side. Receive data is extracted from the incoming line data before the elastic buffer.
Channel 0 selection is unavailable to this controller.
Table 111 - HDLC2 Select
(Page 2, Address 1BH) (E1)
Bit
Name
Functional Description
7
- -
Reserved. Must be kept at 0 for normal operation.
6-0
CP6-0
Custom Pulse. These bits provide the capability for programming the magnitude setting for
the TTIP/TRING line driver A/D converter during the first phase of a mark. The greater the
binary number loaded into the register, the greater the amplitude driven out. This feature is
enabled when the control bit 3 - CPL of the Custom Tx Pulse Enable Register - address 11H
of Page 2 is set high
Table 112 - Custom Pulse Word 1
(Page 2, Address 1CH) (E1)
120
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Bit
Name
Functional Description
Reserved. Must be kept at 0 for normal operation.
7
- -
6-0
CP6-0
Custom Pulse. These bits provide the capability for programming the magnitude setting for
the TTIP/TRING line driver A/D converter during the second phase of a mark. The greater
the binary number loaded into the register, the greater the amplitude driven out. This feature
is enabled when the control bit 3 - CPL of the Custom Tx Pulse Enable Register - address
11H of Page 2 is set high
Table 113 - Custom Pulse Word 2
(Page 2, Address 1DH) (E1)
Bit
Name
Functional Description
7
- -
Reserved. Must be kept at 0 for normal operation.
6-0
CP6-0
Custom Pulse. These bits provide the capability for programming the magnitude setting for
the TTIP/TRING line driver A/D converter during the third phase of a mark. The greater the
binary number loaded into the register, the greater the amplitude driven out. This feature is
enabled when the control bit 3 - CPL of the Custom Tx Pulse Enable Register - address 11H
of Page 2 is set high
Table 114 - Custom Pulse Word 3
(Page 2, Address 1EH) (E1)
Bit
Name
Functional Description
7
- -
Reserved. Must be kept at 0 for normal operation.
6-0
CP6-0
Custom Pulse. These bits provide the capability for programming the magnitude setting for
the TTIP/TRING line driver A/D converter during the fourth phase of a mark. The greater the
binary number loaded into the register, the greater the amplitude driven out. This feature is
enabled when the control bit 3 - CPL of the Custom Tx Pulse Enable Register - address 11H
of Page 2 is set high
Table 115 - Custom Pulse Word 4
(Page 2, Address 1FH) (E1)
121
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
20.5 Master Status 1 (Page 03H) (E1)
Address
Register
Function
(A4A3A2A1A0)
10H (Table 117)
11H (Table 118)
Synchronization Status Word
Alarm Status Word 1
Timer Status Word
SYNC MFSYNC CRCSYN REB1 REB2
CRCRF RED CRCIWK
CRCS1 CRCS2 RFAIL LOSS AIS16S AISS
RAIS RCRS
12H (Table 119)
13H (Table 120)
1SEC, 2SEC, 400T, 8T, CALN, KLVE, T1,T2
Most Significant Phase Status Word
RSLIP, RSLPD, RxFRM, AUXP, RxFT,
RxSBD2-0
14H (Table 121)
15H (Table 122)
16H (Table 123)
17H (Table 124)
18H (Table 125)
19H (Table 126)
1AH (Table 127)
1BH (Table 128)
Least Significant Phase Status Word
Receive Frame Alignment Signal
Receive Signal Status Word
Jitter Attenuator Status Word
Receive Non-frame Alignment Signal
Receive Multiframe Alignment Signal
Sa Bits Report Word
RxTS4-0, RxBC2-0
RIU0 &RFA2-8
LLOS
JACS, JACF, JAE, JAF4, JAFC, JAE4, JAF
RIU1, RNFAB, RALM, &RNU4-8
RMAI1-4, X1, Y, X2, & X3
Sa5, Sa6nibble, C8Sa6, CSa6, RxSa3-0
Alarm Status Word 2
RAIS, AISS, AIS16S, LOSS, AUXPS,
MFALMS, SLIPS
1CH
---
Analog Peak Detector
---
Reserved.
AP7-0
1DH (Table 129)
1EH
Reserved.
Set to 01111000
1FH (Table 130)
Identification Word
Table 116 - Master Status 1 (Page 3) (E1)
122
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Bit
Name
Functional Description
7
SYNC
Receive Basic Frame Alignment. SYNC indicates the basic frame alignment status (1 -
loss; 0 - acquired).
6
5
4
3
2
MFSYNC Receive Multiframe Alignment. MFSYNC indicates the multiframe alignment status (1 -
loss; 0 -acquired).
CRCSYN Receive CRC-4 Synchronization. CRCSYN indicates the CRC-4 multiframe alignment
status (1 - loss; 0 - acquired).
REB1
REB2
Receive E-Bit One Status. REB1 indicates the status of the received E1 bit of the last
multiframe.
Receive E-Bit Two Status. REB2 indicates the status of the received E2 bit of the last
multiframe.
CRCRF
CRC-4 Reframe. A one indicates that the receive CRC-4 multiframe synchronization could
not be found within the time out period of 8 msec. after detecting basic frame
synchronization. This will force a reframe when the maintenance option is selected and
automatic CRC-4 interworking is de-selected.
1
0
RED
RED Alarm. RED goes high when basic frame alignment has been lost for at least
100 msec. This bit will be low when basic frame alignment is acquired (I.431).
CRCIWK CRC-4 Interworking. CRCIWK indicates the CRC-4 interworking status (1 - CRC-to-CRC;
0 - CRC-to-non-CRC).
Table 117 - Synchronization Status Word
(Page 3, Address 10H) (E1)
123
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MT9076B
Data Sheet
Bit
Name
Functional Description
7
CRCS1 Receive CRC Error Status One. If one, the evaluation of the last received submultiframe 1
resulted in an error. If zero, the last submultiframe 1 was error free. Updated on a
submultiframe 1 basis.
6
5
CRCS2 Receive CRC Error Status Two. If one, the evaluation of the last received submultiframe 2
resulted in an error. If zero, the last submultiframe 2 was error free. Updated on a
submultiframe 2 basis.
RFAIL
Remote CRC-4 Multiframe Generator/Detector Failure. If one, then each of the previous
five seconds have an E-bit error count of greater than 989, and for this same period the
receive RAI bit was zero (no remote alarm), and for the same period the SYNC bit was equal
to zero (basic frame alignment has been maintained). If zero, indicates normal operation.
4
LOSS
Loss of Signal Status. If one, indicates the presence of a loss of signal condition. If zero,
indicates normal operation. A loss of signal condition occurs when excess consecutive bit
periods are zero. The threshold for this condition is set by the control bit L32Z. If L32Z is set
high the threshold is 32 successive zeros. If L32Z is set low the threshold is 192 successive
zeros. A loss of signal condition terminates when an average ones density of at least 12.5%
has been received over a period of 192 contiguous pulse positions starting with a pulse.
3
2
AIS16S Alarm Indication Signal 16 Status. If one, indicates an all ones alarm is being received in
channel 16. If zero, normal operation. Updated on a frame basis.
AISS
RAIS
Alarm Indication Status Signal. If one, indicates that a valid AIS or all ones signal is being
received. If zero, indicates that a valid AIS signal is not being received. The criteria for AIS
detection is determined by the control bit ASEL.
1
0
Remote Alarm Indication Status. If one, there is currently a remote alarm condition (i.e.,
received A bit is one). If zero, normal operation. Updated on a non-frame alignment frame
basis.
RCRS
RAI and Continuous CRC Error Status. If one, there is currently an RAI and continuous
CRC error condition. If zero, normal operation. Updated on a multiframe basis.
Table 118 - Alarm Status Word 1
(Page 3, Address 11H) (continued) (E1)
124
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MT9076B
Data Sheet
Bit
Name
Functional Description
7
1SEC One Second Timer Status. This bit changes state once every 0.5 second and is synchronous
with the 2SEC timer. This feature is not available when the device is operated in freerun
mode.
6
5
4
3
2SEC Two Second Timer Status. This bit changes state once every second and is synchronous
with the 1SEC timer.This feature is not available when the device is operated in freerun mode.
400T
8T
400 msec. Timer Status. This bit changes state when the 400 msec. CRC-4 multiframe
alignment timer expires.
8 msec. Timer Status. This bit changes state when the 8 msec. CRC-4 multiframe alignment
timer expires.
CALN CRC-4 Alignment. This bit changes state every millisecond. When CRC-4 multiframe
alignment has been achieved state changes of this bit are synchronous with the receive
CRC-4 synchronization signal.
2
1
0
KLVE
Keep Alive. This bit is high when the AIS status bit has been high for at least 100 msec. This
bit will be low when AIS goes low (I.431).
T1
Timer One. This bit will be high upon loss of terminal frame synchronization persisting for
100 msec. This bit shall be low when T2 becomes high. Refer to I.431 Section 5.9.2.2.3.
T2
Timer Two. This bit will be high when the MT9076 acquires terminal frame synchronization
persisting for 10 msec. This bit shall be low when non-normal operational frames are
received. I.431 Section 5.9.2.2.3.
Table 119 - Timer Status Word
(Page 3, Address 12H) (E1)
125
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MT9076B
Data Sheet
Bit
Name
Functional Description
7
RSLIP
Receive Slip. A change of state (i.e., 1-to-0 or 0-to-1) indicates that a receive controlled
frame slip has occurred.
6
RSLPD
Receive Slip Direction. If one, indicates that the last received frame slip resulted in a
repeated frame, i.e., system clock is faster than network clock. If zero, indicates that the
last received frame slip resulted in a lost frame, i.e., system clock is slower than network
clock. Updated on an RSLIP occurrence basis.
5
4
RXFRM
AUXP
Receive Frame Delay. The most significant bit of the Receive Slip Buffer Phase Status
Word. If one, the delay through the receive elastic buffer is greater than one frame in
length; if zero, the delay through the receive elastic buffer is less than one frame in length.
Auxiliary Pattern. This bit will go high when a continuous 101010... bit stream (Auxiliary
Pattern) is received on the PCM 30 link for a period of at least 512 bits. If zero, auxiliary
pattern is not being received. This pattern will be decoded in the presence of a bit error
rate of as much as 10-3.
3
RxFT
Receiver Frame Toggle. This bit toggles on the falling edge of RxTS4.
2-0
RxSBD2-0 Receive Sub Bit Delay. The three least significant bits of the Receive Slip Buffer Phase
Status Word. They indicate the clock, half clock and one eight clock cycle depth of the
phase status word sample point (bits 2, 1, o respectively).
Table 120 - Most Significant Phase Status Word
(Page 3, Address 13H) (E1)
Bit
Name
Functional Description
7 - 3 RxTS4 - 0 Receive Time Slot. A five bit counter that indicates the number of time slots between the
receive elastic buffer internal write frame boundary and the ST-BUS read frame boundary.
The count is updated every 250 uS.
2 - 0 RxBC2 - 0 Receive Bit Count. A three bit counter that indicates the number of STBUS bit times there
are between the receive elastic buffer internal write frame boundary and the ST-BUS read
frame boundary. The count is updated every 250 uS.
Table 121 - Least Significant Phase Status Word
(Page 3, Address 14H) (E1)
Bit
Name
Functional Description
7
RIU0
Receive International Use Zero. This is the bit which is received on the PCM 30
2048 kbit/sec. link in bit position one of the frame alignment signal. It is used for the CRC-4
remainder or for international use.
6 - 0
RFA2-8 Receive Frame Alignment Signal Bits 2 to 8. These bit are received on the PCM 30
2048 kbit/sec. link in bit positions two to eight of frame alignment signal. These bits form the
frame alignment signal and should be 0011011.
Table 122 - Receive Frame Alignment Signal
(Page 3, Address 15H) (E1)
126
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MT9076B
Data Sheet
Bit
Name
Functional Description
7
LLOSS LIU Loss of Signal indication. This bit will be high if the received signal is below the
threshold selected by ELOS (page 2, address 10H) for a period of at least 1 msec. This bit
will be low for normal operation.
6-0
- - -
Unused.
Table 123 - Receive Signal Status Word
(Page 3, Address 16H) (E1)
Bit
Name
Functional Description
7
JACS
Jitter Attenuated Clock Slow. If one it indicates that the dejittered clock period is increased
by 1/16 UI. If zero the clock is at normal speed.
6
JACF
Jitter Attenuated Clock Fast. If one it indicates that the dejittered clock period is decreased
by 1/16 UI. If zero the clock is at normal speed.
5
4
JAE
Jitter Attenuator FIFO Empty. If one it indicates that the JA FIFO is empty.
JAF4
Jitter Attenuator FIFO with 4 Full Locations. If one it indicates that the JA FIFO has at
least 4 full locations.
3
2
JAFC
JAE4
Jitter Attenuator Center Full. If one it indicates that the JA FIFO is at least half full.
Jitter Attenuator FIFO with 4 Empty Locations. If one it indicates that the JA FIFO has at
most 4 empty locations.
1
0
JAF
- - -
Jitter Attenuator FIFO Full. If one it indicates that the JA FIFO is full.
Unused.
Table 124 - Jitter Attenuator Status Word
(Page 3, Address 17H) (E1)
127
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Bit
Name
Functional Description
7
RIU1
Receive International Use 1. This bit is received on the PCM 30 2048 kbit/sec. link in bit
position one of the non-frame alignment signal. It is used for CRC-4 multiframe alignment or
international use.
6
5
RNFAB Receive Non-frame Alignment Bit. This bit is received on the PCM 30 2048 kbit/sec. link in
bit position two of the non-frame alignment signal. This bit should be one in order to
differentiate between frame alignment frames and non-frame alignment frames.
RALM
Receive Alarm. This bit is received on the PCM 30 2048 kbit/sec. link in bit position three
(the A bit) of the non-frame alignment signal. It is used as a remote alarm indication (RAI)
from the far end of the PCM 30 link (1 - alarm, 0 - normal).
4-0
RNU4-8 Receive National Use Four to Eight. These bits are received on the PCM 30 2048 kbit/sec.
link in bit positions four to eight (the Sa bits) of the non-frame alignment signal.
Table 125 - Receive Non-Frame Alignment Signal
(Page 3, Address 18H) (E1)
Bit
Name
Functional Description
7-4 RMAI1-4 Receive Multiframe Alignment Bits One to Four. These bits are received on the PCM 30
2048 kbit/sec. link in bit positions one to four of time slot 16 of frame zero of every signaling
multiframe. These bit should be 0000 for proper signaling multiframe alignment.
3
X1
Receive Spare Bit X1. This bit is received on the PCM 30 2048 kbit/sec. link in bit position
five of time slot 16 of frame zero of every signaling multiframe.
2
Y
Receive Y-bit. This bit is received on the PCM 30 2048 kbit/sec. link in bit position six of time
slot 16 of frame zero of every signaling multiframe. The Y bit may indicate loss of multiframe
alignment at the remote end (1 -loss of multiframe alignment; 0 - multiframe alignment
acquired).
1-0
X2, X3 Receive Spare Bits X2 and X3. These bits are received on the PCM 30 2048 kbit/sec. link in
bit positions seven and eight respectively, of time slot 16 of frame zero of every signaling
multiframe.
Table 126 - Receive Multiframe Alignment Signal
(Page 3, Address 19H) (E1)
128
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Bit
Name
Functional Description
7
Sa5
Sa 5 Bit. The Sa5 bit is latched and reported here upon receipt of the eighth of
consecutive instance of a new Sa6 nibble.
6
5
CSa6nibble Changed Sa6 Nibble. This bit changes state upon detection of a change of state of
incoming Sa6 nibbles.
C8Sa6
CSa6
Changed Eight Sa6 Bit. This bit toggles upon receipt of the eighth of consecutive
instance of a new Sa6 nibble.
4
Changed Sa6 Bit. This bit toggles in the event of a change of state in the received Sa6 bit.
3 - 0
RxSa 3-0 Receive Sa Nibble Three to Zero. This register contains the contents of the last Sa6
nibble received. It is updated upon receipt of the eighth of consecutive instance of a new
Sa6 nibble.
Table 127 - Sa Bits Report Word
(Page 3, Address 1AH) (E1)
Bit
Name
Functional Description
7
RAIS
Remote Alarm Indication Status. If one, there is currently a remote alarm condition (i.e.,
received A bit is one). If zero, normal operation. Updated on a non-frame alignment frame
basis.
6
AISS
Alarm Indication Status Signal. If one, indicates that a valid AIS or all ones signal is being
received. If zero, indicates that a valid AIS signal is not being received. The criteria for AIS
detection is determined by the control bit ASEL.
5
4
AIS16S Alarm Indication Signal 16 Status. If one, indicates an all ones alarm is being received in
channel 16. If zero, normal operation. Updated on a frame basis.
LOSS
Loss of Signal Status. If one, indicates the presence of a loss of signal condition. If zero,
indicates normal operation. A loss of signal condition occurs when an excess consecutive bit
periods are zero. The threshold for this condition is set by the control bit L32Z. If L32Z is set
high the threshold is 32 successive zeros. If L32Z is set low the threshold is 192 successive
zeros. A loss of signal condition terminates when an average ones density of at least 12.5%
has been received over a period of 192 contiguous pulse positions starting with a pulse.
3
AUXPS Auxiliary Pattern Status. This bit goes on high when a continuous 101010... bit stream
(Auxiliary Pattern) is received on the PCM 30 link for a period of at least 512 bits. If zero,
auxiliary pattern is not being received. This pattern will be decoded in the presence of a bit
error rate of as much as 10-3.
2
1
0
MFALMS Multiframe Alarm Status. This bit goes high in the event of receipt of a multiframe alarm. It
goes low when the received multiframe alarm bit goes low.
RSLIPS Receive Slip Status. A change of state (i.e., 1-to-0 or 0-to-1) indicates that a receive
controlled frame slip has occurred.
- - -
Unused.
Table 128 - Alarm Status Word 2
(Page 3, Address 1BH) (E1)
129
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Bit
Name
Functional Description
7 - 0
AP7-0
Analog Peak Detector. This status register gives the output value of a 8 bit A/D converter
connected to a peak detector on RTIP/RRING.
Table 129 - Analog Peak Detector
(Page 3, Address 1DH) (E1)
Bit
7-0
Name
ID7-0
Functional Description
ID Number. Contains device code 01111000
Table 130 - Identification Word
(Page 3, Address 1FH) (E1)
130
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
21.0 Master Status 2 (Page-4)
21.1 Master Status 2 (Page 04H) (E1)
Address
Register
Function
(A4A3A2A1A0)
10H (Table 132) PRBS Error Counter
PS7-0
11H (Table 133) CRC Multiframe counter for PRBS
12H (Table 134) Alarm Reporting Latch
PSM7-0
RAI, AIS, AIS16, LOS, AUXP, MFALM, RSLIP
13H (Table 135) Errored Frame Alignment Signal Counter
14H (Table 136) E-bit Error Counter Ebt
EFAS7-0
EC15-EC8
EC7-EC0
15H (Table 137) E-bit Error Counter Ebt
16H (Table 138) Most Significant Line Code Violation Error LCV15 - LCV8
Counter
17H (Table 139) Least Significant Line Code Violation Error LCV7 - LCV0
Counter
18H (Table 140) CRC- 4 Error Counter CEt
19H (Table 141) CRC- 6 Error Counter CEt
1AH
CC15-CC8
CC7 - CC0
Unused.
1BH (Table 142) Interrupt Word Zero
TFSYNI, MFSYNI, CRCSYNI,AISI, LOSI,
CEFI,YI, RxSLPI
1CH (Table 143) Interrupt Word One
1DH (Table 144) Interrupt Word Two
1EH (Table 145) Interrupt Word Three
1FH (Table 146) Overflow Reporting Latch
FERRI, CRCERRI, EBITI, AIS16I, LCVI,
PRBSERRI, AUXPI, RAII,
FERRO,CRCO,FEBEO,LCVO,PRBSO,PRBS
MFO, SaI
HDLC0I,HDLC1I,HDLC2,JAI,1SECI,5SECI,RC
RI,SIGI
FERROL,CRCOL,FEBEOL,LCVOL, PRBSOL,
PRBSMFOL
Table 131 - Master Status 2 (Page 4) (E1)
Bit
Name
Functional Description
7 - 0
PS7-0
This counter is incremented for each PRBS error detected on any of the receive channels
connected to the PRBS error detector.
Table 132 - PRBS Error Counter
(Page 4, Address 10H) (E1)
131
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Data Sheet
Bit
Name
Functional Description
7 - 0
PSM7-0 This counter is incremented for each received CRC multiframe. It is cleared when the
PRBS Error Counter is written to.
Table 133 - CRC Multiframe Counter for PRBS
(Page 4, Address 11H) (E1)
Bit
Name
Functional Description
7
RAI
Remote Alarm Indication. This bit is set to one in the event of receipt of a remote alarm,
i.e., A(RAI) = 1. It is cleared when the register is read.
6
5
4
3
2
1
0
AIS
Alarm Indication Signal. This bit is set to one in the event of receipt of an all ones alarm.
It is cleared when the register is read.
AIS16
LOS
AIS Time Slot 16 Alarm. This bit is set to one in the event of receipt of an all ones alarm
in the time slot 16. It is cleared when the register is read.
Loss of Signal. This bit is set to one in the event of loss of received signal. It is cleared
when the register is read.
AUXP
Auxiliary Alarm. This bit is set to one in the event of receipt of the auxiliary alarm pattern.
It is cleared when the register is read.
MFALM Multiframe Alarm. This bit is set to one in the event of receipt of a multiframe alarm. It is
cleared when the register is read.
RSLIP
- - -
Received Slip. This bit is set to one in the event of receive elastic buffer slip. It is cleared
when the register is read.
Unused.
Table 134 - Alarm Reporting Latch
(Page 4, Address 12H) (E1)
Bit
Name
Functional Description
7 - 0
EFAS7 - 0 Errored FAS Counter. An 8 bit counter that is incremented once for every receive frame
alignment signal that contains one or more errors.
Table 135 - Errored Frame Alignment Signal Counter
(Page 4, Address 13H) (E1)
Bit
Name
Functional Description
1-0
EC15-8 E bit Error Counter. The most significant bits of the E bit error counter.
Table 136 - E-bit Error Counter
(Page 4, Address 14H) (E1)
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Zarlink Semiconductor Inc.
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Data Sheet
Bit
Name
Functional Description
7 - 0
EC7-0 E bit Error Counter. The least significant 8 bits of the E-bit error counter.
Table 137 - E-bit Error Counter
(Page 4, Address 15H) (E1)
Bit
Name
Functional Description
7 - 0
LCV15 - 8 Most Significant Bits of the LCV Counter. The most significant eight bits of a 16 bit
counter that is incremented once for every line code violation received. A line code is
defined as a bipolar violation that is not a part of HDB3 encoding where the control bit EXZ
is set low. Where EXZ is set high a violation is defined as either a non-HDB3 bipolar
violation or an occurrence of excess zeros.
Table 138 - Most Significant Bits of the LCV Counter
(Page 4, Address 16H) (E1)
Bit
Name
Functional Description
7 - 0
LCV7 - 0 Least Significant Bits of the LCV Counter. The least significant eight bits of a 16 bit
counter that is incremented once for every line code violation received. A line code is
defined as a bipolar violation that is not a part of HDB3 encoding where the control bit EXZ
is set low. Where EXZ is set high a violation is defined as either a non-HDB3 bipolar
violation or an occurrence of excess zeros.
Table 139 - Least Significant Bits of the LCV Counter
(Page 4, Address 17H) (E1)
Bit
Name
Functional Description
7-0
CC15 - 8 CRC-4 Error Counter These are the most significant eight bits of the CRC-6 error counter.
Table 140 - CRC-4 Error Counter CEt
(Page 4, Address 18H) (E1)
Bit
Name
Functional Description
7 - 0
CC7 - 0 CRC-6 Error Counter. These are the least significant eight bits of the CRC-4 error counter.
Table 141 - CRC-6 Error Counter CEt
(Page 4, Address 19H) (E1)
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Data Sheet
Bit
Name
Functional Description
7
TFSYNI Terminal Frame Synchronization Interrupt. When unmasked this interrupt bit goes high
whenever a change of state of terminal frame synchronization condition exists. Reading this
register clears this bit.
6
5
MFSYNI Multiframe Synchronization Interrupt. When unmasked this interrupt bit goes high
whenever a change of state of multiframe synchronization condition exists. Reading this
register clears this bit.
CRCSYNI CRC-4 Synchronization Interrupt. When unmasked this interrupt bit goes high whenever
change of state of CRC-4 synchronization condition exists. Reading this register clears this
bit.
4
3
AISI
Alarm Indication Signal Interrupt. When unmasked this interrupt bit goes high whenever a
change of state of received all ones condition exists. Reading this register clears this bit.
LOSI
Loss of Signal Interrupt. When unmasked this interrupt bit goes high whenever a loss of
signal (either analog - received signal 20 or 40 dB below nominal or digital - excess
consecutive 0’s received) condition exists.
2
CEFI
YI
Consecutively Errored Frame Alignment Interrupt. When unmasked this interrupt bit
goes high whenever the last two frame alignment signals have errors. Reading this register
clears this bit.
1
0
Receive Y-bit Interrupt. When unmasked this interrupt goes high whenever loss of
multiframe alignment occurs. Reading this register clears this bit.
RxSLPI Receive SLIP Interrupt. When unmasked this interrupt bit goes high whenever a controlled
frame slip occurs in the receive elastic buffer. Reading this register clears this bit.
Table 142 - Interrupt Word Zero
(Page 4, Address 1BH) (E1)
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Data Sheet
Bit
Name
Functional Description
7
FERRI
Errored Framing Alignment Signal Interrupt. When unmasked this interrupt bit goes
high whenever an erroneous bit in frame alignment signal is detected (provided the circuit
is in terminal frame sync). Reading this register clears this bit.
6
5
4
3
CRCERRI CRC-4 Error Interrupt. When unmasked this interrupt bit goes high whenever a local
CRC-4 error occurs. Reading this register clears this bit.
EBITI
AIS16I
LCVI
Receive E-bit Error Interrupt. When unmasked this interrupt bit goes high upon
detection of a wrong E-bit in multiframe. Reading this register clears this bit.
Alarm Indication Signal Interrupt. When unmasked this interrupt bit goes high whenever
all ones in time slot 16 occur.Reading this register clears this bit.
Bipolar Violation Interrupt. When unmasked this interrupt bit goes high whenever a line
code violation (excluding HDB3 encoding) is encountered. Reading this register clears this
bit.
2
PRBSERRI Pseudo Random Bit Sequence Error Interrupt. When unmasked this interrupt bit goes
high upon detection of an error with a channel selected for PRBS testing. Reading this
register clears this bit.
1
0
AUXPI
Auxiliary Pattern Alarm Interrupt. When unmasked this interrupt bit goes high whenever
a sequence of 512 bit consecutive 101010. occur. Reading this register clears this bit.
RAII
Remote alarm Indication Interrupt. When unmasked this interrupt bit goes high
whenever the bit 3 of non-frame alignment signal is high. Reading this register clears this
bit.
Table 143 - Interrupt Word One
(Page 4, Address 1CH) (E1)
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Zarlink Semiconductor Inc.
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Data Sheet
Bit
Name
Functional Description
7
FERRO
Errored Framing Alignment Signal Counter Overflow Interrupt. When unmasked this
interrupt bit goes high whenever the errored frame alignment signal counter changes from
FFH to 00H. Reading this register clears this bit.
6
CRCO
CRC Error Counter Overflow Interrupt. When unmasked this interrupt bit goes high
whenever the CRC error counter changes from FFH to 00H. Reading this register clears
this bit.
5
4
- - -
Unused.
FEBEO
E-bit Counter Overflow Interrupt. When unmasked this interrupt bit goes high whenever
the E-bit counter changes from FFH to 00H. Reading this register clears this bit.
3
2
1
0
LCVO
Line Code Violation Counter Overflow Interrupt. When unmasked this interrupt bit goes
high whenever the line code violation counter changes from FFH to 00H. Reading this
register clears this bit.
PRBSO
Pseudo Random Bit Sequence Error Counter Overflow Interrupt. When unmasked
this interrupt bit goes high whenever the PRBS error counter changes from FFH to 00H.
Reading this register clears this bit.
PRBSMFO Pseudo Random Bit Sequence Multiframe Counter Overflow Interrupt. When
unmasked this interrupt bit goes high whenever the multiframe counter attached to the
PRBS error counter overflows. FFH to 00H. 1 - unmasked, 0 - masked.
SaI
Sa Bit Interrupt. When unmasked this interrupt goes high whenever either a change of
state of any of the received Sa bits Sa5, Sa6, Sa7 or Sa8 (SaBorNi = 1) or a change of
state of any of the received Sa nibbles (SaBorNi = 0). The control bit SaBorNi is located in
page 1 address 12H bit 4.
Table 144 - Interrupt Word Two
(Page 4, Address 1DH) (E1)
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Data Sheet
Bit
Name
Functional Description
7
HDLC0I HDLC0 Interrupt. Whenever an unmasked HDLC0 interrupt occurs, this bit goes high.
Reading this register clears this bit.
6
5
4
HDLC1I HDLC1 Interrupt. Whenever an unmasked HDLC1 interrupt occurs, this bit goes high.
Reading this register clears this bit.
HDLC2I HDLC2 Interrupt. Whenever an unmasked HDLC2 interrupt occurs, this bit goes high.
Reading this register clears this bit.
JAI
Jitter Attenuator Error Interrupt. Whenever an unmasked JAI interrupt occurs.
If jitter attenuator FIFO comes within four bytes of an overflow or underflow, this bit goes
high. Reading this register clears this bit.
3
1SECI
One Second Status Interrupt. When unmasked this interrupt bit goes high whenever the
1SEC status bit (page 3 address 12H bit 7) goes from low to high. Reading this register
clears this bit.
2
1
0
5SECI
RCRI
SIGI
Five Second Status Interrupt. When unmasked this interrupt bit goes high whenever the 5
SEC status bit goes from low to high. Reading this register clears this bit.
RCRI Interrupt. Whenever an unmasked RCRI interrupt occurs. If remote alarm and CRC
error occur this bit goes high. Reading this register clears this bit.
Signaling Interrupt. When unmasked this interrupt bit goes high whenever a change of
state (optionally debounced - see DBEn in the Data Link, signaling Control Word) is
detected in the signaling bits (AB or ABCD) pattern. Reading this register clears this bit.
Table 145 - Interrupt Word Three
(Page 4, Address 1EH) (E1)
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Data Sheet
Bit
Name
Functional Description
7
FERROL
Errored Frame Alignment Signal Counter Overflow Latch. This bit is set when
the errored frame alignment signal counter overflows. It is cleared after being read.
6
5
CRCOL
CRC Error Counter Overflow Latch. This bit is set when the crc error counter
overflows. It is cleared after being read.
FEBEOL
E bit Counter Overflow Latch. This bit is set when E bit counter overflows. It is
cleared after being read.
4
3
- - -
LCVOL
Line Code Violation Counter Overflow Latch. This bit is set when the line code
violation counter overflows. It is cleared after being read.
2
1
PRBSOL
Pseudo Random Bit Sequence Error Counter Overflow Latch. This bit is set
when the PRBS error counter overflows. It is cleared after being read.
PRBSMFOL
Pseudo Random Bit Sequence Multiframe Counter Overflow Latch. This bit is
set when the multiframe counter attached to the PRBS error counter overflows. It is
cleared after being read
0
- - -
Unused.
Table 146 - Overflow Reporting Latch
(Page 4, Address 1FH) (E1)
21.2 Per Channel Transmit signaling (Pages 5 and 6) (E1)
Page 05H, addresses 10000 to 11111, and page 06H addresses 10000 to 10111 contain the Transmit signaling
Control Words for Channel Associated signaling (CAS) channels 2 to 16 and 18 to 32 respectively. Table 147
illustrates the mapping between the addresses of these pages and the CAS channel numbers. Control of these bits
for any one channel is through the processor or controller port when the Per Time Slot Control bit RPSIG bit is high.
Table 148 describes bit allocation within each of these registers.
Page 5-6 Address:
0
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
10 11 12 13 14 15
Equivalent CAS
channel
10 11 12 13 14 15 16
Page 6 Address:
0
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15
Equivalent CAS
channel
17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32
Table 147 - Page 5, 6 Address Mapping to CAS signaling Channels (E1)
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Data Sheet
Bit
Name
Functional Description
7 - 4
3 - 0
- - -
Unused.
A(n)
B(n)
C(n)
D(n)
Transmit signaling Bits for Channel n. These bits are transmitted on the PCM 30
2048 kbit/sec. Link in bit positions one to four of time slot 16 in frame n (when
n = 1 to 15), and are the A, B, C, D signaling bits associated with channel n.
Table 148 - Transmit Channel Associated Signalling (E1) (Pages 5 and 6)
Serial per channel transmit signaling control through CSTI is selected when RPSIG bit is zero. Table 149 describes
the function of CSTI time slots 1 to 30. if MSN bit is high, CSTI time slots 17 to 31 are selected. if MSN bit is low,
CSTI time slots 1 to 15 are selected.
Bit
Name
Functional Description
7 - 4
A(n),
B(n),
C(n),
D(n)
Transmit signaling Bits for Channel n. These bits are transmitted on the PCM 30
2048 kbit/sec. Link in bit positions one to four of time slot 16 in frame n (where
n = 1 to 15), and are the A, B, C, D signaling bits associated with channel n.
3 - 0
A(n),
B(n),
C(n),
D(n)
Transmit signaling Bits for Channel n. These bits are transmitted on the PCM 30
2048 kbit/sec. Link in bit positions one to four of time slot 16 in frame n (where
n = 1 to 15), and are the A, B, C, D signaling bits associated with channel n.
Table 149 - E1 / Transmit Channels Usage - CSTi
NOTE: This table illustrates bit mapping on the serial input stream - it does not refer to an internal register.
21.3 Per Time Slot Control Words (Pages 7 and 8) (E1)
The control functions described by Table 151 are repeated for each PCM-30 channel. Page 07H addresses 10H to
1FH correspond to time slots 0 to 15, while page 08H addresses 10H to 1FH correspond to time slots 16 to 31.
Table 150 illustrates the mapping between the addresses of these pages and the CEPT channel numbers.
Page 8H Address:
0
0
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
10 11 12 13 14 15
10 11 12 13 14 15
Equivalent PCM 30
Timeslots
Page 9H Address:
0
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15
Equivalent PCM 30
Timeslots
16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Table 150 - Mapping between the addresses of these pages and the CEPT channel numbers
139
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Data Sheet
Bit
Name
Functional Description
7
TXMSG Transmit Message Mode. if high, the data from the corresponding address location of Tx
message mode buffer is transmitted in the corresponding PCM 30 time slot. If zero, the data
on DSTI is transmitted on the corresponding PCM 30 time slot.
6
5
ADI
Alternate Digit Inversion. If one, the corresponding transmit time slot data on DSTI has
every second bit inverted. If zero, this bit has no effect on channel data.
RTSL
Remote Time Slot Loopback. If one, the corresponding PCM 30 receive time slot is
looped to the corresponding PCM 30 transmit timeslot. This received time slot will also be
present on DSTO. If zero, the loopback is disabled.
4
3
LTSL
TTST
Local Time Slot Loopback. If one, the corresponding transmit time slot is looped to the
corresponding receive time slot. This transmit time slot will also be present on the transmit
PCM 30 stream. If zero, this loopback is disabled.
Transmit Test. If one, a test signal, either digital milliwatt (when control bit ADSEQ is one)
or PRBS (215-1) (ADSEQ is zero), will be transmitted in the corresponding PCM 30 time
slot. More than one time slot may be activated at once. If zero, the test signal will not be
connected to the corresponding time slot.
2
1
0
RTST
RPSIG
- - -
Receive Test. If one, the corresponding DSTo time slot will be used for testing. If control bit
ADSEQ is one, a digital milliwatt signal will be transmit onto the DSTo channel. If ADSEQ is
zero the receive channel will be connected to the PRBS detector (215-1).
Serial Signaling Enable. If one, the transmit CAS signaling will be controlled by
programming Page 05H. If zero, the transmit CAS signaling will be controlled through the
CSTI stream.
Unused.
Table 151 - Per Time Slot Control Words (Pages 7 and 8) (E1)
21.4 Per Channel Receive signaling (Pages 9 and 0AH) (E1)
Page 09H, addresses 10001 to 11111, and page 0AH addresses 10001 to 11111 contain the Receive signaling
Control Words for CAS channels 2 to 16 and 18 to 32. Table 153 illustrates the mapping between the addresses of
these pages and the CAS channel numbers. Table 154 describes bit allocation within each of these registers.
Page 9 Address:
0
0
1
1
2
2
3
3
4
4
5
5
6
6
7
7
8
8
9
9
10 11 12 13 14 15
10 11 12 13 14 15
Equivalent PCM 30
Timeslots
Page A Address:
0
1
2
3
4
5
6
7
8
9
10 11 12 13 14 15
Equivalent PCM 30
Timeslots
16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Table 152 - Page 9 and A Address Mapping to CAS Channels (E1)
140
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Bit
Name
Functional Description
7 - 4
3 - 0
- - -
Unused
Receive signaling Bits for Channel n. These bits are received on the PCM 30
2048 kbit/sec. Link in bit positions one to four of time slot 16 in frame n (where n = 1 to 30)
and are the A, B, C, D signaling bits associated with channel n.
A(n)
B(n)
C(n)
D(n)
Table 153 - Receive Channel Associated signaling (Pages 9 and A) (E1)
Serial per channel receive signaling status bits appear on ST-BUS stream CSTo. Table 157 describes the bit
allocation within each of the 30 active ST-BUS time slot of CSTo.
Bit
Name
Functional Description
7 - 4
A(n),
B(n),
C(n),
D(n)
Transmit signaling Bits for Channel n. These bits are transmitted on the PCM 30
2048 kbit/sec. Link in bit positions one to four of time slot 16 in frame n (where
n = 1 to 15), and are the A, B, C, D signaling bits associated with channel n.
3 - 0
A(n),
B(n),
C(n),
D(n)
Transmit signaling Bits for Channel n. These bits are transmitted on the PCM 30
2048 kbit/sec. Link in bit positions one to four of time slot 16 in frame n (where
n = 1 to 15), and are the A, B, C, D signaling bits associated with channel n.
Table 154 - Receive CAS Channels (CSTo) (E1)
141
Zarlink Semiconductor Inc.
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Data Sheet
22.0 HDLC Control and Status
(Page B for HDLC0, Page C for HDLC1 and Page D for HDLC2)
Register
Address
Function
Control (Write/Verify)
Status (Read)
10H (Table 156)
11H (Table 157)
Address Recognition 1
Address Recognition 2
TX FIFO
- --
- --
ADR16-10,A1EN
ADR26-20, A2EN
BIT7-0
12H (Table
RX FIFO
158/Table 159)
13H (Table 160)
HDLC Control 1
- --
- --
ADREC, RxEN, TxEN, EOP, FA,
Mark-idle, TR, FRUN
14H (Table 161)
HDLC Status
INTGEN, Idle-Chan, RQ9, RQ8,
TxSTAT2, TxSTAT1, RxSTAT2,
RxSTAT1
15H (Table 162)
16H (Table 163)
HDLC Control 2
Interrupt Mask
- --
- --
INTSEL, CYCLE, TxCRCI, SEVEN,
RxFRST, TxFRST
GaIM, RxEOPIM, TxEOPIM, RxFEIM,
TxFLIM, FA:TxUNDERIM, RxFFIM,
RxOVFIM
17H (Table 164)
- --
Interrupt Status (*)
Ga, RxEOP, TxEOP, RxFE, TxFL,
FA:TxUNDER, RxFF, RxOVF
18H (Table 165)
19H (Table 166)
1AH (Table 167)
1BH (Table 168)
- --
- --
Rx CRC MSB
Rx CRC LSB
- --
CRC15-CRC8
CRC7-CRC0
TxCNT7-0
Low TX byte count
Test Control
- --
HRST, RTLOOP, CRCTST, FTST,
ARTST, HLOOP
1CH (Table 169)
1DH (Table 170)
1EH (Table 171)
1FH (Table 172)
- --
Test Status
RxCLK, TxCLK, VCRC, VADDR
RSV, RFD2-0,RSV, TFD2-0
RSV, RFFS2-0, RSV, TFLS2-0
TxCNT15-8
HDLC Control 3
HDLC Control 4
- --
- --
- --
Extended TX byte
count
Table 155 - HDLC0, HDLC1, HDLC2 Control and Status (Pages B, C, and D)
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MT9076B
Data Sheet
Bit
Name
Functional Description
7 - 2
ADR16-11 Address 16 - 11. A six bit address used for comparison with the first byte of the received
address. ADR16 is MSB.
1
0
ADR10
A1EN
Address 10. This bit is used in address comparison if a seven bit address is being
checked for (control bit four of control register 2 is set).
First Address Comparison Enable. When this bit is high, the above six (or seven) bit
address is used in the comparison of the first address byte.
If address recognition is enabled, any packet failing the address comparison will not be
stored in the RX FIFO. A1EN must be high for All-call (1111111) address recognition for
single byte address. When this bit is low, this bit mask is ignored in address comparison
Table 156 - HDLC Address Recognition Register 1
(Pages B, C, and D, Address 10H)
Bit
Name
Functional Description
7 - 1
ADR26-20 Address 26 - 20. A seven bit address used for comparison with the second byte of the
received address. ADR26 is MSB. This mask is ignored (as well as first byte mask) if all
call address (1111111) is received.
0
A2EN
Second Address Comparison Enable. When this bit is set high, the above seven bit
address is used in the comparison of the second address byte.
If address recognition is enabled, any packet failing the address comparison will not be
stored in the RX FIFO. A2EN must be high for All-call address recognition. When this bit
is low, this bit mask is ignored in address comparison.
Table 157 - HDLC Address Recognition Register 2
(Pages B,C, and D, Address 11H)
Bit
Name
Functional Description
7 - 0
BIT7-0 This eight bit word is tagged with the two status bits from the control register 1 (EOP and FA),
and the resulting 10 bit word is written to the TX FIFO. The FIFO status is not changed
immediately after a write or read occurs. It is updated after the data has settled and the
transfer to the last available position has finished.
Table 158 - TX FIFO Write Register
(Pages B, C, and D, Address 12H)
Bit
Name
Functional Description
7 - 0
BIT7-0 This is the received data byte read from the RX FIFO. The status bits of this byte can be read
from the status register. The FIFO status is not changed immediately when a write or read
occurs. It is updated after the data has settled and the transfer to the last available position
has finished.
Table 159 - RX FIFO Read Register
(Pages B, C, and D, Address 12H)
143
Zarlink Semiconductor Inc.
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Data Sheet
Bit
Name
Functional Description
7
ADREC
Address Recognition. When high this bit will enable address recognition. This forces the
receiver to recognize only those packets having the unique address as programmed in the
Receive Address Recognition Registers or if the address is an All call address.
6
5
RxEN
TxEN
Receive Enable. When low this bit will disable the HDLC receiver. The receiver will disable
after the rest of the packet presently being received is finished. The receiver internal clock
is disabled.
When high the receiver will be immediately enabled and will begin searching for flags,
Go-aheads etc.
Transmit Enable. When low this bit will disable the HDLC transmitter. The transmitter will
disable after the completion of the packet presently being transmitted. The transmitter
internal clock is disabled.
When high the transmitter will be immediately enabled and will begin transmitting data, if
any, or go to a mark idle or interframe time fill state.
4
3
EOP
FA
End of Packet. Forms a tag on the next byte written the TX FIFO, and when set will
indicate an end of packet byte to the transmitter, which will transmit an FCS following this
byte. This facilitates loading of multiple packets into TX FIFO. Reset automatically after a
write to the TX FIFO occurs.
Frame Abort. Forms a tag on the next byte written to the TX FIFO, and when set will
indicate to the transmitter that it should abort the packet in which that byte is being
transmitted. Reset automatically after a write to the TX FIFO.
2
1
Mark-Idle Mark - Idle. When low, the transmitter will be in an idle state. When high it is in an
interframe time fill state. These two states will only occur when the TX FIFO is empty.
TR
Transparent Mode. When high this bit will enable transparent mode. This will perform the
parallel to serial conversion without inserting or deleting zeros. No CRC bytes are sent or
monitored nor are flags or aborts. A falling edge of TxEN for transmit and a falling edge of
RxEN for receive is necessary to initialize transparent mode. This will also synchronize the
data to the transmit and receive channel structure. Also, the transmitter must be enabled
through control register 1 before transparent mode is entered.
0
FRUN
Freerun. When high the HDLC TX and RX are continuously enabled providing the RxEN
and TxEN bits are set.
Table 160 - HDLC Control Register 1
(Pages B, C, and D, Address 13H)
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Data Sheet
Bit
Name
Functional Description
7
INTGEN
Interrupt Generated. Set to 1 when an interrupt (in conjunction with the Interrupt Mask
Register) has been generated by the HDLC. This is an asynchronous event. It is reset
when the interrupt Register is read.
6
Idle Chan Idle Channel. Set to a 1 when an idle Channel state (15 or more ones) has been detected
at the receiver. This is an asynchronous event. On power reset, this may be 1 if the clock
(RXC) was not operating. Status becomes valid after the first 15 bits or the first zero is
received.
5 - 4
RQ9, RQ8 Byte Status bits from RX FIFO. These bits determine the status of the byte to be read
from RX FIFO as follows:
RQ9 RQ8 Byte Status
0
0
1
1
0
1
0
1
Packet Byte
First Byte
Last byte of a good packet.
Last byte of a bad packet.
3 - 2
TxSTAT2-1 These bits determine the status of the TX FIFO as follows:
TxSTAT2 TxSTAT1 TX FIFO Status
0
0
0
1
TX FIFO full up to the selected status level or more.
The number of bytes in the TX FIFO has reached or
exceeded the selected interrupt threshold level.
TX FIFO empty.
The number of bytes in the TX FIFO is less than the
selected interrupt threshold level.
1
1
0
1
1 - 0 RxSTAT2 - 1 These bits determine the status of the RX FIFO as follows:
RxSTAT2 RxSTAT1 RX FIFO Status
0
0
0
1
RX FIFO empty
The number of bytes in the RX FIFO is less
than the interrupt threshold level.
RX FIFO full.
The number of bytes in the RX FIFO has reached or
exceeded the interrupt threshold level.
1
1
0
1
Table 161 - HDLC Status Register
(Pages B, C, and D Address 14H)
145
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Bit
Name
Functional Description
7
INTSEL Interrupt Selection. When high, this bit will cause bit 2 of the Interrupt Register to reflect a
TX FIFO underrun (TXunder). When low, this interrupt will reflect a frame abort (FA).
6
5
CYCLE Cycle. When high, this bit will cause the transmit byte count to reload one minus the value
initially loaded into the Transmit Byte Count Register.
TxCRCI Transmit CRC Inhibited. When high, this bit will inhibit transmission of the CRC. That is, the
transmitter will not insert the computed CRC onto the bit stream after seeing the EOP tag
byte. This is used in V.120 terminal adaptation for synchronous protocol sensitive UI frames.
4
SEVEN Seven Bit Address Recognition. When high, this bit will enable seven bits of address
recognition in the first address byte. The received address byte must have bit 0 equal to 1
which indicates a single address byte is being received.
3
2
1
- -
- -
Reserved, must be zero for normal operation.
Reserved, must be zero for normal operation.
RxFRST RX FIFO Reset. When high, the RX FIFO will be reset. This causes the receiver to be
disabled until the next reception of a flag. The status register will identify the FIFO as being
empty. However, the actual bit values in the RX FIFO will not be reset.
0
TxFRST TX FIFO Reset. When high, the TX FIFO will be reset. The Status Register will identify the
FIFO as being empty. This bit will be reset when data is written to the TX FIFO. However, the
actual bit values of data in the TX FIFO will not be reset. It is cleared by the next write to the
TX FIFO.
Table 162 - HDLC Control Register 2
(Pages B, C, and D, Address 15H)
Bit
Name
Functional Description
7-0
GaIM
This register is used with the Interrupt Register to mask out the interrupts that are
RxEOPIM TxEOPIM not required by the microprocessor. Interrupts that are masked out will not drive the
RxFEIM
TxFLIM
FA:TxUNDERRIM
RxFFIM
pin IRQ low; however, they will set the appropriate bit in the Interrupt Register. An
interrupt is disabled when the microprocessor writes a 0 to a bit in this register.
This register is cleared on power reset.
RxOVFIM
Table 163 - HDLC Interrupt Mask Register
(Pages B, C, and D, Address 16H)
146
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Bit
Name
Functional Description
7
GA
Go Ahead. Indicates a go-ahead pattern was detected by the HDLC receiver. This bit is
reset after a read.
6
RxEOP
End Of Packet Detected. This bit is set when an end of packet (EOP) byte was written into
the RX FIFO by the HDLC receiver. This can be in the form of a flag, an abort sequence or
as an invalid packet. This bit is reset after a read.
5
4
TxEOP
RxFE
Transmit End Of Packet. This bit is set when the transmitter has finished sending the
closing flag of a packet or after a packet has been aborted. This bit is reset after read.
End Of Packet Read. This bit is set when the byte about to be read from the RX FIFO is the
last byte of the packet. It is also set if the Rx FIFO is read and there is no data in it. This bit
is reset after a read.
3
2
TXFL
FA:
TX FIFO Low. This bit is set when the Tx FIFO is emptied below the selected low threshold
level. This bit is reset after a read.
Frame Abort/TX FIFO Underrun. When Intsel bit of Control Register 2 is low, this bit (FA) is
TxUNDER set when a frame abort is received during packet reception. It must be received after a
minimum number of bits have been received (26) otherwise it is ignored.
When INTSEL bit of Control Register 2 is high, this bit is set for a TX FIFO underrun
indication. If high it Indicates that a read by the transmitter was attempted on an empty Tx
FIFO.
This bit is reset after a read.
1
0
RXFF
RX FIFO Full. This bit is set when the Rx FIFO is filled above the selected full threshold
level. This bit is reset after a read.
RxOVF
RX FIFO Overflow. Indicates that the 128 byte RX FIFO overflowed (i.e., an attempt to write
to a 128 byte full RX FIFO). The HDLC will always disable the receiver once the receive
overflow has been detected. The receiver will be re-enabled upon detection of the next flag,
but will overflow again unless the RX FIFO is read. This bit is reset after a read.
Table 164 - HDLC Interrupt Status Register
(Pages B, C, and D, Address 17H)
Bit
Name
Functional Description
7-0
CRC15-8 The MSB byte of the CRC received from the transmitter. These bits are as the
transmitter sent them; that is, most significant bit first and inverted. This register is updated
at the end of each received packet and therefore should be read when end of packet is
detected.
Table 165 - Receive CRC MSB Register
(Pages B, C, and D, Address 18H)
147
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Bit
Name
Functional Description
7-0
CRC7-0 The LSB byte of the CRC received from the transmitter. These bits are as the transmitter
sent them; that is, most significant bit first and inverted. This register is updated at the end of
each received packet and therefore should be read when end of packet is detected.
Table 166 - Receive CRC LSB Register
(Pages B, C, and D, Address 19H)
Bit
7-0
Name
Functional Description
TxCNT7-0
Low Transmit Byte Count Register. This register, along with the Extended
Transmit Byte Count Register indicates the length of the packet about to be
transmitted. For a packet size of 255 or less it is only necessary to write this
register. When this register reaches the count of one, the next write to the Tx FIFO
will be tagged as an end of packet byte. The counter decrements at the end of the
write to the Tx FIFO. If the Cycle bit of Control Register 2 is set high, the counter will
cycle through the programmed value continuously.
Table 167 - Low Transmit Byte Count Register
(Pages B, C, and D, Address 1AH)
148
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Bit
Name
Functional Description
7
HRST
HDLC Reset. When this bit is set to one, the HDLC will be reset. This is similar to
RESET being applied, the only difference being that this bit will not be reset. This bit
can only be reset by writing a zero twice to this location or applying RESET.
6
RTLOOP
RT Loopback. When this bit is high, receive to transmit HDLC loopback will be
activated. Receive data, including end of packet indication, but not including flags or
CRC, will be written to the TX FIFO as well as the RX FIFO. When the transmitter is
enabled, this data will be transmitted as though written by the microprocessor. Both
good and bad packets will be looped back. Receive to transmit loopback may also
be accomplished by reading the RX FIFO using the microprocessor and writing
these bytes, with appropriate tags, into the TX FIFO.
5
4
3
- -
- -
Reserved. Must be set to 0 for normal operation.
Reserved. Must be set to 0 for normal operation.
CRCTST
CRC Remainder Test. This bit allows direct access to the CRC Comparison
Register in the receiver through the serial interface. After testing is enabled, serial
data is clocked in until the data aligns with the internal comparison (16 RXC clock
cycles) and then the clock is stopped. The expected pattern is F0B8 hex. Each bit
of the CRC can be corrupted to allow more efficient testing.
2
FTST
FIFO Test. This bit allows the writing to the RX FIFO and reading of the TX FIFO
through the microprocessor to allow more efficient testing of the FIFO
status/interrupt functionality. This is done by making a TX FIFO write become a RX
FIFO write and a RX FIFO read become a TX FIFO read. In addition, EOP/FA and
RQ8/RQ9 are re-defined to be accessible (i.e., RX write causes EOP/FA to go to
RX fifo input; TX read looks at output of TX fifo through RQ8/RQ9 bits).
1
0
ARTST
HLOOP
Address Recognition Test. This bit allows direct access to the Address
Recognition Registers in the receiver through the serial interface to allow more
efficient testing. After address testing is enabled, serial data is clocked in until the
data aligns with the internal address comparison (16 RXc clock cycles) and then
clock is stopped.
TR Loopback. When high, transmit to receive HDLC loopback will be activated.
The packetized transmit data will be looped back to the receive input. RXEN and
TXEN bits must also be enabled.
Table 168 - HDLC Test Control Register
(Pages B, C, and D, Address 1BH)
149
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Bit
Name
Functional Description
7-4
3
- -
These bits are reserved.
RxCLK
Receive Clock. This bit represents the receiver clock generated after the RXEN
control bit, but before zero deletion is considered.
2
1
TxCLK
VCRC
Transmit Clock. This bit represents the transmit clock generated after the TXEN
control bit, but before zero insertion is considered.
Valid CRC. This is the CRC recognition status bit for the receiver. Data is clocked
into the register and then this bit is monitored to see if comparison was successful
(bit will be high).
0
VADDR
Valid Address. This is the address recognition status bit for the receiver. Data is
clocked into the Address Recognition Register and then this bit is monitored to see
if comparison was successful (bit will be high).
Table 169 - HDLC Test Status Register
(Pages B, C, and D, Address 1CH)
150
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Bit
Name
Functional Description
7
- --
Unused.
These bits select the Rx FIFO full status level:
6-4
RFD2-0
RFD2
RFD1
RFD0
Full Status Level
0
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
16
32
0
0
48
0
64
1
80
1
96
1
1
112
128
3
- --
Unused.
2-0
TFD2-0
These bits select the Tx HDLC FIFO full status level:
TFD2
TFD1
TFD0
Full Status Level
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
16
32
48
64
80
96
112
128
Table 170 - HDLC Control Register 3
(Pages B, C, and D, Address 1DH)
151
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Bit
Name
Functional Description
7
- --
Unused.
These bits select the RXFF (Rx FIFO Full) interrupt threshold level:
6-4
RFFS2-0
RFFS2
RFFS1
RFFS0
RX FIFO Full Interrupt threshold Level.
0
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
64
72
0
0
80
0
88
1
96
1
104
112
120
1
1
3
- --
Unused.
2-0
TFLS2-0
These bits select the TXFL (Tx FIFO Low) interrupt threshold level:
TFLS2
TFLS1
TFLS0
TX FIFO Low Interrupt threshold Level.
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
8
16
24
32
40
48
56
64
Table 171 - HDLC Control Register 4
(Pages B, C, and D, Address 1EH)
152
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
Bit
Name
Functional Description
7-0
TxCNT15-8 Extended Transmit Byte Count Register. This register, along with the Transmit Byte
Count Register indicates the length of the packet about to be transmitted. Values
programmed into this register are not internally updated until the next write to the Low
Transmit Byte Count Register. When the internal counter decrements to one, the next
write to the Tx FIFO will be tagged as an end of packet byte. The counter decrements at
the end of the write to the Tx FIFO. If the Cycle bit of Control Register 2 is set high, the
counter will cycle through the programmed value continuously.
Table 172 - Extended Transmit Byte Count Register
(Pages B,C, and D, Address 1FH)
23.0 Transmit National Bit Buffer (Page 0EH)
Page 0EH, address 10H to 14H contain the five bytes of the transmit national bit buffer (TNBB0 - TNBB4
respectively). This feature is functional only when control bit NBTB (page 01H, address 17H) is one.
Bit
Name
Functional Description
7 - 0
TNBBn.F1 Transmit San+4 Bits Frames 1 to 15. This byte contains the bits transmitted in bit position
n+4 of channel zero of frames 1, 3, 5, 7, 9, 11, 13 and 15 when CRC-4 multiframe
-
TNBBn.F15 alignment is used, or of consecutive odd frames when CRC-4 multiframe alignment is not
used. n = 0 to 4 inclusive and corresponds to a byte of the receive national bit buffer.
Table 173 - Transmit National Bit Buffer Bytes Zero to Four (Page 0EH)
24.0 Receive National Bit Buffer (Page 0FH)
Page 0FH, addresses 10H to 14H contain the five bytes of the receive national bit buffer (RNBB0 - RNBB4
respectively).
Bit
Name
Functional Description
7 - 0
RNBBn.F1 Receive San+4 Bits Frames 1 to 15. This byte contains the bits received in bit position n+4
of channel zero of frames 1, 3, 5, 7, 9, 11, 13 and 15 when CRC-4 multiframe alignment is
-
RNBBn.F15 used, or of consecutive odd frames when CRC-4 multiframe alignment is not used. n = 0 to
4 inclusive and corresponds to a byte of the receive national bit buffer.
Table 174 - Receive National Bit Buffer Bytes Zero to Four (Page 0FH)
153
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
25.0 AC/DC Electrical Characteristics
Absolute Maximum Ratings* - Voltages are with respect to ground (VSS) unless otherwise stated.
Parameter
Symbol
Min.
Max.
Units
1
2
3
4
5
6
Supply Voltage
VDD
VI
-0.3
-0.3
7
V
Voltage at Digital Inputs
Current at Digital Inputs
Voltage at Digital Outputs
Current at Digital Outputs
Storage Temperature
VDD + 0.3
30
V
mA
V
II
VO
IO
-0.3
VDD + 0.3
30
mA
°C
TST
-65
150
* Exceeding these values may cause permanent damage. Functional operation under these conditions is not implied.
Recommended Operating Conditions - Voltages are with respect to ground (VSS) unless otherwise stated.
Characteristics
Sym.
Min.
Typ.‡
Max. Units
Test Conditions
1
2
Operating Temperature
Supply Voltage
TOP
VDD
-40
3.0
85
°C
V
3.3
3.6
‡
Typical figures are at 25°C and are for design aid only: not guaranteed and not subject to production testing.
DC Electrical Characteristics† - Voltages are with respect to ground (VSS) unless otherwise stated.
Characteristics
Supply Current
Sym.
Min.
Typ.‡
Max.
Units
Test Conditions
1
IDD
85
98
mA
Outputs unloaded.
Transmitting an all 1’s
signal.
2
3
Input High Voltage (Digital
Inputs)
VIH
VIL
2.0
0
VDD
0.8
V
V
Input Low Voltage (Digital
Inputs)
4
5
Input Leakage (Digital Inputs)
IIL
1
1
12*
A
VI= 0 to VDD
Output High Voltage (Digital
Outputs)
VOH
0.8VDD
VSS
VDD
V
IOH = 7 mA, VOH = 2.4 V
6
7
Output Low Voltage (Digital
Outputs)
VOL
IOZ
0.4
12
V
IOL = 2 mA, VOl = 0.4 V
VO = 0 to VDD
High Impedance Leakage
(Digital I/O)
A
† Characteristics are for clocked operation over the ranges of recommended operating temperature and supply voltage.
‡ Typical figures are at 25°C and are for design aid only: not guaranteed and not subject to production testing.
30 A for inputs of boundary scan test port: Osc1,Tdi, Tms, Tclk and Trst.
154
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
AC Electrical Characteristics† - Motorola Microprocessor Timing
Characteristics
Sym.
Min. Typ.‡ Max. Units
Test Conditions
1
2
3
4
5
6
7
8
9
DS low
tDSL
tDSH
tCSS
tRWS
tADS
tCSH
tRWH
tADH
tDDR
tDHR
tDAZ
tDSW
tDHW
70
60
0
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
DS High
CS Setup
R/W Setup
1
Address Setup
CS Hold
4
0
R/W Hold
7
Address Hold
Data Delay Read
4
75
75
75
CL=50 pF
CL=50 pF
10 Data Hold Read
11 Data Active to High Z Delay
12 Data Setup Write
13 Data Hold Write
7
9
†
Characteristics are for clocked operation over the ranges of recommended operating temperature and supply voltage.
‡ Typical figures are at 25°C and are for design aid only: not guaranteed and not subject to production testing.
tCYC
tDSL
VTT
VTT
VTT
DS
tDSH
tCSS
tCSH
CS
tRWH
tRWS
R/W
A0-A4
tADS
tADH
VTT
tDDR
tDAZ
VALID DATA
D0-D7
READ
VTT,VCT
tDHW
tDHR
tDSW
D0-D7
WRITE
VALID DATA
VTT
Note: DS and CS may be connected together.
Figure 15 - Motorola Microport Timing
155
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
AC Electrical Characteristics† - Intel Microprocessor Timing
Characteristics
Sym.
Min.
Typ.‡ Max. Units
Test Conditions
1
2
3
4
5
6
7
8
9
RD low
tRDL
tRDH
tCSS
tCSH
tADS
tADH
tDDR
tDAZ
tDSW
tDHW
70
60
0
ns
ns
ns
ns
ns
ns
RD High
CS Setup
CS Hold
0
Address Setup
Address Hold
4
4
Data Delay Read
Data Active to High Z Delay
Data Setup Write
75
75
ns
ns
ns
ns
CL=50 pF
7
9
10 Data Hold Write
‡Typical figures are at 25°C and are for design aid only: not guaranteed and not subject to production testing.
tCYC
tRDL
RD
VTT
VTT
VTT
tRDH
tCSS
tCSH
CS
tCSH
WR
tADH
tADH
tADS
A0-A4
VTT
tDDR
tDAZ
VALID DATA
D0-D7
READ
VTT
tDSW
tDHW
D0-D7
WRITE
VALID DATA
VTT
Figure 16 - Intel Microport Timing
156
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
AC Electrical Characteristics - JTAG Port Timing
Characteristic Sym. Min.
TCK period width
Typ.
Max. Units
Test Conditions
1
2
3
tTCLK
tTCLKL
tTCLKH
tDISU
tDIH
100
40
40
12
12
12
12
ns BSDL spec’s 12 MHz
TCK period width LOW
ns
ns
TCK period width HIGH
TDI setup time to TCK rising
TDI hold time after TCK rising
TMS setup time to TCK rising
TMS hold time after TCK rising
TDO delay from TCK falling
TRST pulse width
tMSSU
tMSH
tDOD
50
tTRST
25
tmssu
tmsh
TMS
tdih
ttclk
tdisu
TDI
ttclkl
ttclkh
TCK
tdod
TDO
ttrst
TRST
Figure 17 - JTAG Port Timing
157
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
AC Electrical Characteristics - Transmit Data Link Timing (T1 mode)
Characteristic
Sym. Min.
Typ.
Max. Units
Test Conditions
1
2
3
Data Link Clock Pulse Width
Data Link Setup
tDW
324
ns 150 pF
tTDS
tTDH
35
35
ns
ns
Data Link Hold
tDW
VTT,VCT
TxDLCLK
TxDL
tDLH
tDLS
VTT
Figure 18 - Transmit Data Link Timing Diagram (T1 mode)
AC Electrical Characteristics - Transmit Data Link Timing (E1 mode)
Characteristic
Sym. Min.
Typ.
Max. Units
Test Conditions
1
2
3
Data Link Clock Output Delay
Data Link Setup
tTDC
tTDS
tTDH
72
35
35
ns 150 pF
ns
ns
Data Link Hold
C4b
VTT
tTDC
VTT,VCT
TxDLCLK
TxDL
tDLH
tDLS
VTT
Figure 19 - Transmit Data Link Timing Diagram (E1 mode)
158
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
F0b
TIME SLOT 0
Bits 4,3,2,1,0
Example A - 20 kb/s
TxDLCLK
TxDL
Example B - 12 kb/s
TxDLCLK
TxDL
Figure 20 - Transmit Data Link Functional Timing (E1 mode)
AC Electrical Characteristics - Receive Data Link Timing (T1 mode)
Characteristic
Sym. Min.
Typ.
Max. Units
Test Conditions
50 pF
1
2
3
Data Link Clock Output Delay
Data Link Output Delay
RxFP Output Delay
tRDC
tRDD
tRFD
160
45
ns
ns
ns
50 pF
50 pF
45
RxFP
RxDLCLK
RxDL
Figure 21 - Receive Data Link Functional Timing (T1 mode)
159
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
tRFD
RxFP
E1.5o
VTT,VCT
tRFD
VTT
tRDC
VTT,VCT
RxDLCLK
RxDL
tRDD
VTT,VCT
Figure 22 - Receive Data Link Diagram (T1 mode)
AC Electrical Characteristics - Receive Data Link Timing (E1 mode)
Characteristic
Sym. Min.
Typ.
Max. Units
Test Conditions
50 pF
1
2
3
Data Link Clock Output Delay
Data Link Output Delay
RxFP Output Delay
tRDC
tRDD
tRFD
160
45
ns
ns
ns
50 pF
50 pF
45
RxFP
TIME SLOT 0
Bits 4,3,2,1,0
Example A - 20 kb/s
RxDLCLK
RxDL
Example B - 12 kb/s
RxDLCLK
RxDL
Figure 23 - Receive Data Link Functional Timing (E1 mode)
160
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
VTT
E2o
tRDC
tRDC
VTT,VCT
RxDLCLK
RxDL
tRDD
VTT,VCT
Figure 24 - Receive Data Link Timing Diagram (E1 mode)
AC Electrical Characteristics - ST-BUS Timing (E1 or T1 mode)
Characteristic
Sym. Min.
Typ.
Max. Units
Test Conditions
1
2
3
4
5
6
7
8
9
C4b Clock Width High or Low
C4b Clock Width High or Low
Frame Pulse Hold
t4W
tFPS
tFPH
tFPS
tFPL
tSIS
80
25
10
10
75
10
10
75
75
122
150
35
ns 2.048 Mb/s mode
ns 8.192 Mb/s mode
30.5
ns
Frame Pulse Setup
Frame Pulse Low
ns 2.048 Mb/s mode
ns
Serial Input Setup
ns
Serial Input Hold
tSIH
ns
Serial Output Delay
Frame Pulse Delay
tSOD
tFDD
ns 150 pF
ns
ST-BUS
Bit Cells
Channel 31
Bit 0
Channel 0
Bit 7
Channel 0
Bit 6
Channel 0
Bit 5
F0b
C4b
Figure 25 - ST-BUS Functional Timing Diagram - 2.048 Mb/s Mode
161
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
ST-BUS
Bit Cells
Channel 127
Bit 0
Channel 0
Bit 7
Channel 0
Bit 6
Channel 0
Bit 5
F0b
C4b
Figure 26 - ST-BUS Functional Timing Diagram - 8.192 Mb/s Mode
ST-BUS Bit
Stream
Bit Cell
Bit Cell
tFPH
Bit Cell
F0b
(Input)
VTT
tFPL
tFPS
t4WI
t4WI
C4b
(Input)
VTT
tSIH
All Input
Streams
VTT
tSIS
tSOD
All Output
Streams
VTT,VCT
Figure 27 - ST-BUS Timing Diagram (Input Clocks)
162
Zarlink Semiconductor Inc.
MT9076B
Data Sheet
ST-BUS Bit
Stream
Bit Cell
Bit Cell
Bit Cell
F0b
(Output)
VTT
t4WO
tFPD
tFPD
C4b
(Output)
VTT
t4WO
tSIH
All Input
Streams
VTT
tSIS
tSOD
All Output
Streams
VTT,VCT
Figure 28 - ST-BUS Timing Diagram (Output Clocks)
AC Electrical Characteristics - Multiframe Timing (T1 or E1 mode)
Characteristic
Sym. Min.
Typ.
Max. Units
Test Conditions
1
2
3
Receive Multiframe Output Delay
Transmit Multiframe Setup
Transmit Multiframe Hold
tMOD
tMS
50
50
50
ns 150 pF
ns
ns * 256 C2 periods -100 nsec
tMH
*
Frame 0
Bit 5 Bit 4
Frame 12 or 24
Bit 5 Bit 4
DSTo
BIt Cells
Bit 7
Bit 6
Bit 0
Bit 7
Bit 6
Bit 0
Bit 7
F0b
C4b
(4.096 MHz)
RxMF
Figure 29 - Receive Multiframe Functional Timing (T1 mode)
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Zarlink Semiconductor Inc.
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Data Sheet
Frame 15
Bit 5 Bit 4
Frame 0
Bit 4
DSTo
BIt Cells
Bit 7
Bit 6
Bit 0
Bit 7
Bit 6
Bit 5
Bit 0
Bit 7
F0b
C4b
(4.096 MHz)
RxMF
(Tx8KEN = 0)
Figure 30 - Receive Multiframe Functional Timing (E1 mode)
Frame N
Bit 5 Bit 4
Frame 0
Bit 4
DSTi
Bit Cells
Bit 7
Bit 6
Bit 0
Bit 7
Bit 6
Bit 5
Bit 0
Bit 7
F0b
C4b
(4.096 MHz)
TxMF
Figure 31 - Transmit Multiframe Functional Timing (T1 mode or E1 mode)
VTT
F0b
tMOD
VTT
C4b
tMOD
RxMF(1,2)
VTT,VCT
tMH2
tMH
tMS
TxMF(1)
VTT
Note (1) : These two signals do not have a defined phase relationship
Note (2): Control bit Tx8KEN set low.
Figure 32 - Multiframe Timing Diagram (T1 mode or E1 mode)
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Data Sheet
AC Electrical Characteristics - TXA/TXB (E1 or T1 mode)
Characteristic Sym. Min.
Serial Output Delay
TxFP Output Delay
Typ.
Max.
Units
Test Conditions
150 pF
150 pF
1
2
tSOD
20
20
ns
ns
tTFOD
Channel 23
Bit 0
Sbit
Channel 0
Bit 7
Channel 0
Bit 6
TXA/TXB
RxMF/TxFP
(Tx8KEN= 1)
E1.5o/Exclk
(LIUEN = 1)
Figure 33 - TXA/TXB Functional Timing (T1 mode)
Channel 0
Bit 6
Channel 0
Bit 5
Channel 31
Bit 0
Channel 0
Bit 7
TXA/TXB
RxMF/TxFP
(Tx8KEN= 1)
E1.5o/Exclk
(LIUEN = 1)
Figure 34 - TXA/TXB Functional Timing (E1 mode)
TxFP
(Output)
VTT
tTFOD
tTFOD
E1.5o
VTT
(Output)
tSOD
tSOD
VTT
TXA/TXB
(Output)
Figure 35 - TXA/TXB Timing Diagram (T1 mode or E1 mode)
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Data Sheet
AC Electrical Characteristics - IMA Timing (E1 or T1 mode)
Characteristic
Sym. Min.
Typ.
Max. Units
Test Conditions
E1 mode
1
2
3
4
5
6
C4b Clock Width High or Low
Frame Pulse Setup
Frame Pulse Hold
t4W
tFPS
tFPS
tSIS
80
10
10
4
122
150
ns
ns
ns
ns
ns
ns
Serial Input Setup
Serial Input Hold
tSIH
tSOD
4
Serial Output Delay
45
150 pF
Channel 23
Sbit
Channel 0
Bit 7
Channel 0
Bit 6
DSTi
Bit 0
F0b
C4b
1.544 MHz
Figure 36 - Tx IMA Functional Timing (T1 mode)
Channel 23
Bit 0
Channel 23
Bit 1
Sbit
DSTo
RXFP
Exclk
1.544 MHz
Figure 37 - Rx IMA Functional Timing (T1 mode)
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Zarlink Semiconductor Inc.
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Data Sheet
Channel 31
Bit 0
Channel 0
Bit 6
Channel 0
Bit 7
Channel 0
Bit 5
DSTi
F0b
C4b
2.048 MHz
Figure 38 - Tx IMA Functional Timing (E1 mode)
Channel 0
Bit 6
DSTo
RXFP
Channel 0
Bit 7
Channel 31
Bit 0
Exclk
2.048 MHz
Figure 39 - Rx IMA Functional Timing (E1 mode)
ST-BUS Bit
Stream
Bit Cell
Bit Cell
F0b
(Input)
VTT
tFPH
tFPS
C4b
(Input)
VTT
tSIS
VTT
DSTi
tSIH
Figure 40 - Tx IMA Timing Diagram (T1 mode or E1 mode)
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Data Sheet
ST-BUS Bit
Stream
Bit Cell
Bit Cell
RxFP
(Output)
VTT
Exclk
(Output)
VTT
tSIS
VTT
DSTo
tSOD
Figure 41 - Rx IMA Timing Diagram (T1 mode or E1 mode)
1.5 ms
FRAME
12
FRAME
1
FRAME
11
FRAME
12
Sbit
FRAME
• • • • • • • •
1
CHANNEL
1
CHANNEL
2
CHANNEL
CHANNEL
24
Sbit
• • • •
23
125 s
Least
Significant
Bit (Last)
Most
Significant
Bit (First)
BIT
1
BIT
2
BIT
3
BIT
4
BIT
5
BIT
6
BIT
7
BIT
8
5.2 s
Figure 42 - D4 Format
2.0 ms
FRAME
15
FRAME
0
FRAME
14
FRAME
15
FRAME
0
• • • • • • • •
TIME SLOT
0
TIME SLOT
1
TIME SLOT
30
TIME SLOT
31
• • • •
125 s
Least
Significant
Bit (Last)
Most
Significant
Bit (First)
BIT
1
BIT
2
BIT
3
BIT
4
BIT
5
BIT
6
BIT
7
BIT
8
(8/2.048) s
Figure 43 - PCM 30 Format
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Data Sheet
125s
CHANNEL
31
CHANNEL
30
CHANNEL
0
CHANNEL
0
CHANNEL
31
• • •
Most
Significant
Least
Significant
Bit (Last)
BIT
7
BIT
6
BIT
3
BIT
2
BIT
1
BIT
5
BIT
0
BIT
4
Bit (First)
3.906 s
Figure 44 - ST-BUS Stream Format - 2.048 Mb/s
125s
CHANNEL
127
CHANNEL
126
CHANNEL
0
CHANNEL
CHANNEL
127
0
• • •
Most
Significant
Least
Significant
Bit (Last)
BIT
0
BIT
7
BIT
6
BIT
3
BIT
2
BIT
1
BIT
5
BIT
4
Bit (First)
0.977s
Figure 45 - ST-BUS Stream Format 8.192 Mb/s
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Zarlink Semiconductor Inc.
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