cx28394 Conexant Systems, Inc., cx28394 Datasheet - Page 179

• Manufacturer Part Number: cx28394
• Description: Quad/x16/octal-t1/e1/j1 Framers
• Manufacturer: Conexant Systems, Inc.

CX28394/28395/28398
Quad/x16/Octal—T1/E1/J1 Framers
Table 3-16. T1 Transmit Framer Modes (T1/E1N = 1)
Table 3-17. Criteria for E1 Loss/Recovery of Transmit Frame Alignment
100054E
FAS
MFAS
CAS
TFRAME
0000
100X
1100
0100
0101
0001
1101
Mode
FT Only
SF
SF + JYEL
SLC
ESF + No CRC
ESF + Mimic CRC
ESF + Force CRC
Framer 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 are satisfied:
NOTE(S):
restarts in frame N+2.
Transmit Loss of Frame (TLOF) alignment is declared when:
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.
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•
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•
•
•
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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.
Three consecutive FAS pattern errors are detected, where FAS pattern consists of a 7-bit (x0011011)
pattern in FAS frames as well as bit 2 equalling one in NFAS frames.
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 8ms 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, then the search
Ones
Yes
Yes
Yes
Fs
–
–
–
F-bit Overhead Insertion
Conexant
FPS
Yes
Yes
Yes
–
–
–
–
Description
CRC6
Ones
Yes
Yes
–
–
–
–
Yes
Yes
Yes
Yes
Ft
–
–
–
3.12 Transmitter Registers
YEL
YB2
YB2
YB2
YB2
YB2
YB2
YJ
Yellow Alarms
3.0 Registers
MYEL
YF
YF
YF
–
–
–
–
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