ds21ft40 Maxim Integrated Products, Inc., ds21ft40 Datasheet - Page 73

• Manufacturer Part Number: ds21ft40
• Description: Ds21ft40 Four X Three 12 Channel E1 Framer
• Manufacturer: Maxim Integrated Products, Inc.

DS21FT40 FRAMER SYNCHRONIZATION FLOWCHART Figure 16-13
RCR1.0 = 0
RLOS = 1
Resync if
Increment CRC4
Sync Counter;
CRC4SA = 0
CRC4 Resync
CAS Resync
Criteria Met;
Set CASRC
Criteria Met
(RIR.2)
Set FASRC
(RIR.0)
(RIR.1)
CRC4 Word Errors
FAS Resync
Criteria Met
Check for >=915
Time
8ms
Out
Out of 1000
Check for CAS
MF Word Error
CRC4 Multiframe Search
(if enabled via CCR1.0)
CRC4 Sync Criteria
Met; CRC4SA = 0;
Sync Counter
(depends on RCR1.2)
Reset CRC4
CRC4SA = 1
Check for FAS
Framing Error
If CRC4 is on
(CCR1.0 = 1)
(CCR1.3 = 0)
If CAS is on
73 of 87
Sync Declared
FAS Search
Criteria Met
FASSA = 1
FASSA = 0
RLOS = 1
Power Up
FAS Sync
RLOS = 0
CAS Multiframe Search
(if enabled via CCR1.3)
Criteria Met
CASSA = 0
CAS Sync
CASSA = 1
DS21FT40