Nortel NT1R20, Description, Page: 45 / 316

Description Page 21 of 290
Line cards Description
DS-30Y network loops extend between controller cards and superloop
network cards in the common equipment and function in a manner similar to
DS-30X loops (see Figure 5). Essentially, a DS-30Y loop carries the PCM
timeslot traffic of a DS-30X loop. Four DS-30Y network loops form a
superloop with a capacity of 128 channels (120 usable timeslots). See
Meridian 1 system engineering (553-3001-151) for more information on
superloops.
Card LAN link
Maintenance communications is the exchange of control
and status data between IPE line or trunk cards and the CE CPU by way of
the NT8D01 Controller Card. Maintenance data is transported via the card
LAN link. This link is composed of two asynchronous serial buses (called the
Async card LAN link in Figure 6). The output bus is used by the Meridian 1
controller for output of control data to the line card. The input bus is used by
the Meridian 1 controller for input of line card status data.
Figure 7
DS-30X loop data format
29
W0B7 W31DV
DS-30X loop
data words
Frame
sync
Frame sync
DS-30X loop
data bits
5.12 MHz
2.56 MHz
SB = SIGNALING BIT DV = DATA VALID
30 31 0 1 2 3 4
W0B6 W0B5 W0B4 W0B3 W0B2 W0B1 W0B0 W0SB W0DV W1B7
553-6151