D-channel interface – Nortel Networks 1000 User Manual
Page 771
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Architecture
771
combinations each for µ255 to µ255, µ255 to A-law, A-law to µ255, and
A-law to A-law. These values are selected to meet the EIA loss and level
plan.
Table 322
Digital pad values and offset allocations
Offset
PAD set 0
PAD set 1
0
0dB
-7db
1
2dB
-8db
2
3dB
-9db
3
4dB
-10db
4
5dB
0.6db
5
6.1dB
7db
6
8dB
9db
7
-1dB
10db
8
-3dB
11db
9
-4dB
12db
A
idle code, 7F
3db
B
unassigned code, FF
14db
C
1dB
spare
D
-2dB
spare
E
-5db
spare
F
-6db
spare
D-channel interface
The D-channel interface is a 64 Kbps maximum, full-duplex, serial
bit-stream configured as a DCE device. The data signals include receive
data output, transmit data input, receive clock output, and transmit clock
output. The receive and transmit clocks can vary slightly from each other
as determined by the transmit and receive carrier clocks.
Feature selection through software configuration for the D-channel
includes:
•
56 Kbps
•
64 Kbps clear
•
64 Kbps inverted (64 Kbps restricted)
DCHI can be enabled and disabled independent of the PRI card, as long
as the PRI card is inserted in its cabinet slot. The D-channel data link
cannot be established however, unless the PRI loop is enabled.
Nortel Communication Server 1000
Circuit Card Reference
NN43001-311
02.06
Standard
27 August 2008
Copyright © 2003-2008 Nortel Networks
.