Rainbow Electronics DS2154 - Manual (Page 56)

DS2154
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DS2154 SYNCHRONIZATION FLOWCHART Figure 13–10
POWER UP
RLOS=1
FAS SYNC
SYNC DECLARED
CRITERIA MET
FASSA=0
CAS MULTIFRAME
SEARCH (IF ENABLED
VIA CCR1.3)
CASSA=1
CAS SYNC
CRITERIA MET
CASSA=0
RLOS=0
RLOS=1
RESYNC IF
RCR1.1=0
INCREMENT CRC4
SYNC COUNTER;
CRC4SA=0
8 MS
TIME
OUT
CRC4 MULTIFRAME
SEARCH (IF ENABLED
VIA CCR 1.0)
CRC4SA=1
CRC4 SYNC CRITERIA
MET; CRC4SA=0;
RESET CRC4 SYNC
COUNTER
SET FASRC
(RIR.1)
FAS RESYNC
CRITERIA MET
CHECK FOR FAS
FRAMING ERROR
(DEPENDS ON
RCR1.2)
CRC4 RESYNC
CRITERIA MET
CHECK FOR >=915
OUT OF 1000 CRC
CRC WORD ERROS
IF CRC4 IS ON
(CCR1.0=1)
CAS RESYNC
CRITERIA MET;
SET CASRC
(RIR.0)
CHECK FOR CAS
MF WORD ERROR
IF CAS IS ON
(CCR1.3=0)
(RIR.2)
FAS SEARCH
FASSA=1