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

• Card-LAN / echo / test port interface
• 80C51FA Microcontroller

DS-30X interface

NTBK50 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.
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 238: Digital Pad - values and offset allocations
attenuation levels (1.0dB is 1 dB of loss and –1.0 dB is 1 dB of gain.
Table 238: 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 555. The values shown are
PAD SET 1
Offset
0 0.0 dB
1 -1.0 dB
2 -2.0 dB
3 -3.0 dB
4 -4.0 dB
5 -5.0 dB
6 -6.0 dB
7 -7.0 dB
8 -8.0 dB
9 -9.0 dB
10 -10.0 dB
11 spare
Architecture
PAD
July 2011 555