Datacom DM991C, Product Manual

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Product Manual - DM991 Series V Family - 204.4092.08 72
1 2 3 4 5 6 7 8
0 C1/Si 0 0 1 1 0 1 1
1 0/Si 1 A Sa4 Sa5 Sa6 Sa7 Sa8
2 C2/Si 0 0 1 1 0 1 1
3 0/Si 1 A Sa4 Sa5 Sa6 Sa7 Sa8
4 C3/Si 0 0 1 1 0 1 1
5 1/Si 1 A Sa4 Sa5 Sa6 Sa7 Sa8
6 C4/Si 0 0 1 1 0 1 1
7 0/Si 1 A Sa4 Sa5 Sa6 Sa7 Sa8
8 C1/Si 0 0 1 1 0 1 1
9 1/Si 1 A Sa4 Sa5 Sa6 Sa7 Sa8
10 C2/Si 0 0 1 1 0 1 1
11 1/Si 1 A Sa4 Sa5 Sa6 Sa7 Sa8
12 C3/Si 0 0 1 1 0 1 1
13 E/Si 1 A Sa4 Sa5 Sa6 Sa7 Sa8
14 C4/Si 0 0 1 1 0 1 1
15 E/Si 1 A Sa4 Sa5 Sa6 Sa7 Sa8
II
SMF
Frame
#
Bits 1 to 8 of timeslot 0 of each interface
I
SMF indicates the sub-multiframe. This calculations are used for the CRC4
calculation.
The Si bit is the international bit
The A bit is used to indicate a remote alarm (active in 1).
Sa4 to Sa8 are bits recommended by the ITU-T for point to point specific
aplications.
Sa4 to Sa8 mut remain on 1 when not being used and traverssing an
international barrier.
The E bit is used to indicate CRC4 error. The normal bi status is 1. When a
CRC4 error is detected, the bit corresponding to the sub-multiframe in which the
error was detected is set to 0.
C1 to C4 are used to transmit CRC4 code.
Timeslot 0, which contains the 0011011 sequence is define as the word FAS
and timeslot 0 which does not have FAS is the NFAS.
Table 20. CRC4 multiframe structure
16.1.2. CAS Multiframe (Channel Associated Signaling)
Usually used over lines that transmit voice channels. Its multiframe alignment is performed by timeslot 16,
with no relation to a possible CRC4 multiframe. Table 21 shows the CAS multiframes structures.
CAS and CRC4 structures are fully independent and can be individually disabled by the user.
In the case of signaling by a common channel, timeslot 16 is used. The signal aligning method in this
channel is part of the signaling protocol in use.