STANDARD PRODUCT
PM4351 COMET
DATA SHEET
PMC-1970624
ISSUE 10
COMBINED E1/T1 TRANSCEIVER
Figure 8
- CRC Multiframe Alignment Algorithm
Out of Frame
3 consecutive FASor NFAS
errors; manual reframe; or
excessive CRC errors
FAS_Find_1_Par
FAS_Find_1
NFAS
not found
next frame
FAS
found
NFAS
not found
next frame
FAS
found
NFAS_Find
NFAS_Find_Par
NFAS
FAS
NFAS
FAS
found
next frame
not found
next frame
found
next frame
not found
next frame
FAS_Find_2_Par
FAS_Find_2
FAS
8ms expire
FAS
found
next frame
found
next frame
Start 400ms timer
and 8ms timer
Start 8ms timer
BFA_Par
BFA
8ms expire and
NOT(400ms expire)
400ms
expire
CRCMFA
Reset BFA to
most recently
CRCMFA_Par
found alignment
CRC to CRC
Interworking
CRC to non-CRC
Interworking
CRCMFA_Par
(Optional setting)
PROPRIETARY AND CONFIDENTIAL
43