Ds-30X Interface - Avaya Nortel Communication Server 1000 Reference

DS-30X interface

The NTAK79 interfaces to one DS-30X bus which contains 32 byte-interleaved timeslots
operating at 2.56 Mb. Each timeslot contains 10 bits in A10 message format; eight are assigned
to voice/data (64 kbps), one to signaling (8 kbps), and one is a data valid bit (8 kbps).
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. The
DS-30X timeslot number is mapped to the PCM-30 channel number. Timeslots 0 and 16 are
currently unused for PCM.
Digital PAD
Software selects A-Law or Mu-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 Mu-Law is 7FH. The unequipped code is FFH for both A-Law and Mu-Law. As the
idle code and unequipped code can be country dependent, the software instructs the NTAK79
to use different codes for each direction. The 32 digital pads available are listed in
Digital pad values and offset allocations
levels; 1.0 dB is 1 dB of loss and –1.0 dB is 1 dB of gain.
Table 231: Digital pad values and offset allocations
Offset
0
1
2
3
4
5
6
7
8
9
10
11
Circuit Card Reference
PAD SET 0
PAD
0.6 dB
1.0 dB
2.0 dB
3.0 dB
4.0 dB
5.0 dB
6.1 dB
7.0 dB
8.0 dB
9.0 dB
10.0 dB
11.0 dB
on page 527. The values shown are attenuation
PAD SET 1
Offset
0
1
2
3
4
5
6
7
8
9
10
11
Architecture
Table 231:
PAD
0.0 dB
–1.0 dB
–2.0 dB
–3.0 dB
–4.0 dB
–5.0 dB
–6.0 dB
–7.0 dB
–8.0 dB
–9.0 dB
–10.0 dB
spare
July 2011 527