Nortel Networks 553-3001-211 manual Interconnection, Microprocessor

NTAK09 1.5 Mb DTI/PRI card Page 703 of 894

Architecture

Signaling interface

The signaling interface performs an 8 Kbps signaling for all 24 channels and interfaces directly to the DS-30X link. Messages in both directions of transmission are three bytes long.

Interconnection

The interconnection to the carrier is by NTBK04 1.5 Mb carrier cable.

The NTBK04 is twenty feet long. The NT8D97AX, a fifty-foot extension, is also available.

Microprocessor

The NTAK09 is equipped with bit-slice microprocessors that handle the following major tasks:

•Task handler: also referred to as an executive, the task handler provides orderly per-channel task execution to maintain real-time task ordering constraints.

•Transmit voice: inserts digital pads, manipulates transmit AB bits for DS1, and provides graceful entry into T-Link data mode when the data module connected to the DTI/PRI trunk is answering the call.

•Receive voice: inserts digital pads and provides graceful entry into T-Link data mode when the data module connected to the DTI/PRI trunk is originating the call.

•T-Link data: a set of transmit and receive vectored subroutines which provides T-Link protocol conversion to/from the DM-DM protocol.

•Receive ABCD filtering: filters and debounces the receive ABCD bits and provides change of state information to the system.

•Diagnostics

•Self-test

Circuit Card Description and Installation