Rainbow Electronics DS2143Q - Manual (Page 30)

DS2143/DS2143Q
031397 30/40
DS2143 SYNCHRONIZATION FLOWCHART
POWER UP
RLOS=1
FAS SYNC
SYNC DECLARED
CRITERIA MET
FASSA=0
CAS MULTIFRAME
SEARCH (IF ENABLED
VIA CCR.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.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
WORD ERRORS
IF CRC4 IS ON
(CCR.0=1)
CAS RESYNC
CRITERIA MET;
SET CASRC
(RIR.0)
CHECK FOR CAS
MF WORD ERROR
IF CAS IS ON
(CCR.3=0)