MT9074AL Zarlink Semiconductor, Inc., MT9074AL Datasheet - Page 33

• Manufacturer Part Number: MT9074AL
• Description: T1/E1/J1 Single Chip Transceiver
• Manufacturer: Zarlink Semiconductor, Inc.

MT9074
33
* only if CRC-4 synchronization is selected and automatic CRC-4
** only if automatic CRC-4 interworking is selected.
interworking is de-selected.
only if CRC-4 synchronization is selected and automatic CRC-4
interworking is de-selected
frame alignment. Start CRC-4 processing. E-bits set as
per G.704 and I.431. Indicate CRC synchronization
CRC-to-CRC interworking. Re-align to new basic
>914 CRC errors
in one second
CRC-4 multi-frame alignment
CRC multiframe
8 msec. timer expired*
multiframe alignment.
alignment
Start 400 msec timer.
Find two CRC frame
Start 8 msec timer.
alignment signals.
No CRC
Notes 7& 8.
Note 7.
achieved.
Note 7.
Note 7.
Figure 15 - Synchronization State Diagram
NO
alignment acquired
Basic frame
acquired. Enable traffic RAI=0, E’s=0. Start
loss of primary basic frame alignment
Primary basic frame synchronization
Search for primary basic frame
alignment signal RAI=1, Es=0.
Verify second occurrence of
Verify Bit 2 of non-frame
8 msec
checking. Notes 7 & 8.
frame alignment signal.
Out of synchronization
alignment signal.
multiframe
alignment.
No CRC
RAI = 0
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.
RAI = 1
Parallel search for new basic frame
YES
YES
YES
YES
NO
NO
alignment signal.
Notes 6 & 7.
Check for two consecutive errored
400 msec timer expired
multiframe alignment signals.
Multiframe synchronization
NO
NO
Search for multiframe
acquired as per G.732.
Signaling multi-frame alignment
alignment signal.
Notes 7 & 8.
Note 7.
Note 7.
YES
incorrect frame
Data Sheet
3 consecutive
alignment
signals
YES