Functional Description - Avaya Nortel Communication Server 1000 Reference

NT8D09 Analog Message Waiting Line card

Functional description

The NT8D09 Analog Message Waiting Line card contains a microprocessor that provides the
following functions:
• self-identification
• self-test
• control of card operation
• status report to the controller
• maintenance diagnostics
The NT8D09 Analog Message Waiting Line card also provides:
• 600 ohms balanced terminating impedance
• analog-to-digital and digital-to-analog conversion of transmission and reception signals
for 16 audio phone lines
• transmission and reception of Scan and Signaling Device (SSD) signaling messages over
a DS-30X signaling channel in A10 format
• on-hook/off-hook status and switchhook flash detection
• 20 Hz ringing signal connection and automatic disconnection when the station goes off-
hook
• synchronization for connecting and disconnecting the ringing signal to zero crossing of
ringing voltage
• loopback of SSD messages and Pulse Code Modulation (PCM) signals for diagnostic
purposes
• correct initialization of all features at power-up
• direct reporting of digit dialed (500-type telephones) by collecting dial pulses
• connection of –150 V DC at 1 Hz to activate message waiting lamps
• lamp status detection
• disabling and enabling of selected units for maintenance
Figure 100: Analog message waiting line card - block diagram
diagram of the major functions contained on the analog message waiting line card. Each of
these functions are described in the following sections.
366 Circuit Card Reference
Comments? infodev@avaya.com
on page 367 shows a block
July 2011