Nortel Networks 553-3001-211 Card interfaces, Voice and signaling interfaces, Power interface

NT1R20 Off-Premise Station Analog Line card Page 159 of 894

Card interfaces

Voice and signaling interfaces

The eight line interfaces provided by the NT1R20 OPS analog line card connect to conventional, 2-wire (tip and ring), analog line facilities. Incoming analog voice and signaling information from a line facility is converted by the OPS analog line card to digital form and routed to the CPU over DS-30 network loops. Conversely, digital voice and signaling information from the CPU is sent over DS-30 network loops to the OPS analog line card where it is converted to analog form and applied to the line facility.

The OPS analog line card uses only eight of the 30 available timeslots for its eight line interfaces. The OPS analog line card can be configured in software to format PCM data in the µ-law or A-law conventions.

Maintenance communication

Maintenance communication is the exchange of control and status data between line or trunk cards and the CPU. Maintenance data is transported through the card LAN link.

The card LAN link supports the following functions on the NT1R20 OPS analog line card:

•polling

•reporting of self-test status

•CPU initiated card reset

•reporting of card ID (card type and hardware vintage)

•reporting of firmware version

•reporting of line interface unit configuration

•enabling/disabling of the DS-30X network loop busy

•reporting of card status

Power interface

Power is provided to the NT1R20 OPS analog line card by the NTAK78 ac/dc or NTAK72 DC power supply.

Circuit Card Description and Installation