bt8375kpf Conexant Systems, Inc., bt8375kpf Datasheet - Page 187

• Manufacturer Part Number: bt8375kpf
• Description: Single Chip Transceivers For T1/e1 And Integrated Service Digital Network Isdn Primary Rate Interfaces Systems
• Manufacturer: Conexant Systems, Inc.

Bt8370/8375/8376
Fully Integrated T1/E1 Framer and Line Interface
Table 3-17. Criteria for E1 Loss/Recovery of Transmit Frame Alignment
N8370DSE
FAS
MFAS
CAS
Mode
Basic Frame Alignment (BFA) is recovered when the following search criteria are satisfied:
During FAS only modes, BFA is recovered when the following search criteria is satisfied:
NOTE(S):
frame N+2.
Transmit Loss of Frame (TLOF) alignment is declared when:
pattern in FAS frames, as well as bit 2 equaling 1 in NFAS frames.
MFAS—CRC Multiframe Alignment is recovered when the following search criteria are satisfied:
MFAS errors do not cause Transmit Loss of Frame (TLOF) alignment.
CAS Multiframe Alignment is recovered when the following search criteria are satisfied:
CAS errors do not cause Transmit Loss of Frame (TLOF) alignment.
Three consecutive FAS pattern errors are detected, when the FAS pattern consists of a 7-bit (x0011011)
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FAS pattern (0011011) is found in frame N.
Frame N+1 contains bit 2 equal to 1.
Frame N+2 also contains FAS pattern (0011011).
FAS pattern (0011011) is found in frame N.
No mimics of the FAS pattern present in frame N+1.
FAS pattern (0011011) is found in frame N+2.
BFA is recovered, identifying FAS and NFAS frames.
Within 6 ms after BFA, bit 1 of NFAS frames contains the first MFAS pattern (001011xx).
Within 8 ms after BFA, bit 1 of NFAS frames contains the second MFAS pattern (001011xx), aligned
to first MFAS.
BFA is recovered, identifying TS0 through TS31.
MAS (0000xxxx) Multiframe Alignment Signal pattern is found in the first 4 bits of TS16, and 8 bits
of TS16 in preceding frame contains nonzero value.
If FAS pattern is not found in frame N+2 or FAS mimic is found in frame N+1, the search restarts in
Conexant
Description
3.12 Transmitter Registers
3-69