STANDARD PRODUCT
PM4328 TECT3
DATASHEET
PMC-2011596
ISSUE 1
HIGH DENSITY T1/E1 FRAMER
AND M13 MULTIPLEXER
Figure 7: 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
FAS
found
NFAS
FAS
found
not found
not found
next frame
next frame
NFAS_Find
NFAS_Find_Par
NFAS
FAS
not found
next frame
NFAS
FAS
not found
next frame
found
found
next fram e
next frame
FAS_Find_2_Par
FAS_Find_2
FAS
8ms expire
FAS
found
found
Start 400ms timer
next frame
next frame
and 8ms timer
Start 8ms timer
BFA_Par
8ms expire and
NOT( 400ms expire)
400ms
expire
CRCMFA
Reset BFA to
CRCMFA_Par
most recently
found alignment
CRCto CRC
CRCto non-CRC
Interworking
Interworking
CRCMFA_Par
PROPRIETARY AND CONFIDENTIAL
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PMC [ PMC-SIERRA, INC ]
