Datasheet

DS26518 8-Port T1/E1/J1 Transceiver
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9.9.2 E1 Framing
The E1 framing consists of FAS, NFAS detection as shown in Table 9-14.
Table 9-14. E1 FAS/NFAS Framing
CRC-4
FRAME
#
TYPE 1 2 3 4 5 6 7 8
0 FAS C1 0 0 1 1 0 1 1
1 NFAS 0 1 A Sa4 Sa5 Sa6 Sa7 Sa8
2 FAS C2 0 0 1 1 0 1 1
3 NFAS 0 1 A Sa4 Sa5 Sa6 Sa7 Sa8
4 FAS C3 0 0 1 1 0 1 1
5 NFAS 1 1 A Sa4 Sa5 Sa6 Sa7 Sa8
6 FAS C4 0 0 1 1 0 1 1
7 NFAS 0 1 A Sa4 Sa5 Sa6 Sa7 Sa8
8 FAS C1 0 0 1 1 0 1 1
9 NFAS 1 1 A Sa4 Sa5 Sa6 Sa7 Sa8
10 FAS C2 0 0 1 1 0 1 1
11 NFAS 1 1 A Sa4 Sa5 Sa6 Sa7 Sa8
12 FAS C3 0 0 1 1 0 1 1
13 NFAS E1 1 A Sa4 Sa5 Sa6 Sa7 Sa8
14 FAS C4 0 0 1 1 0 1 1
15 NFAS E2 1 A Sa4 Sa5 Sa6 Sa7 Sa8
C = C bits are the CRC-4 remainder; A = alarm bits; Sa = bits for data link.