Nortel Networks Circuit Card 311 - Manual (Page 977)

Architecture 977
The incoming serial bit stream is converted to 8-bit parallel bytes to be
directed to padding control. The signaling bits are extracted and inserted
by the A07 signaling interface circuitry. Timeslots 0 and 16 are currently
unused for PCM.
Digital PAD
The software selects A-Law or µ-Law and one of 32 possible PAD values
for each channel. These values are provided in a PROM through which the
data is routed. The idle code for A-Law is 54H and for µ-Law is 7FH. The
unequipped code is FFH for both A-Law and µ-Law.
As the idle code and unequipped code can be country dependent, the
software instructs the NTBK50 to use different codes for each direction. The
32 digital pads available are illustrated in
Table 405 "Digital Pad - values and
offset allocations" (page 977) . The values shown are attenuation levels
(1.0dB is 1 dB of loss and –1.0 dB is 1 dB of gain.
Table 405
Digital Pad - values and offset allocations
PAD SET 0 PAD SET 1
Offset PAD Offset PAD
0 0.6 dB 0 0.0 dB
1 1.0 dB 1 -1.0 dB
2 2.0 dB 2 -2.0 dB
3 3.0 dB 3 -3.0 dB
4 4.0 dB 4 -4.0 dB
5 5.0 dB 5 -5.0 dB
6 6.1 dB 6 -6.0 dB
7 7.0 dB 7 -7.0 dB
8 8.0 dB 8 -8.0 dB
9 9.0 dB 9 -9.0 dB
10 10.0 dB 10 -10.0 dB
11 11.0 dB 11 spare
12 12.0 dB 12 spare
13 13.0 dB 13 spare
14 14.0 dB 14 Idle Code
15 spare 15 Unassigned Code
Nortel Communication Server 1000
Circuit Card Reference
NN43001-311 01.04 Standard
Release 5.0 23 May 2008
Copyright © 2003-2008, Nortel Networks
.