Functional description 729
•provide pad control for 2-wire and 4-wire facilityconnections
•enable trunk type and function to be configured on a per-port basis
in software
•provide isolation of foreign potentials from transmission and signaling
circuit
•provide software control of A-Law and µ-Law modes
•support loopback of pulse code modulation (PCM) signals to DS-30X for
diagnostic purposes
The E and M Trunkcard passes voice and signaling data over DS-30X
loops, and maintenance data over the card LAN link.
The E and M Trunkcard contains four identical and independently
configurable trunk interface units (also referred to as circuits). Each
unit provides impedance matching and a balance network in a signal
transformer/analog hybrid circuit. Also provided are relays for placing
outgoing call signaling onto the trunk. Signal detection circuits monitor
incoming call signaling. A Codec performs A/D and D/A conversion of trunk
analog voiceband signals to digital PCM signals.
The four units on the card can operate in the A-Law or the µ-Law
companding mode. The mode is selected by making service change
entries. Each unit can be independently configured for 2-wire E and M,
4-wire E and M, and paging trunk types. The trunk type is selected by
service change entries and jumper strap settings. All units on the card
can perform the following features:
•convert transmission signals from analog-to-digital and digital-to-analog
•provide outpulsing on the card: make/break ratios are defined in
software and downloaded at power-up and by software command
•provide 600-ohm balance and termination impedance (2-wire
configuration)
•provide 600-ohm termination impedance (4-wire configuration)
•provide pad control for 2-wire and 4-wire facilityconnections
•allow trunk type and function to be configured on a per port basis in
software
•provide isolation of foreign potentials from transmission and signaling
circuit
•provide software control of A-Law and µ-Law modes
•support loopback of pulse code modulation (PCM) signals to DS-30X for
diagnostic purposes
Nortel Communication Server 1000
Circuit Card Reference
NN43001-311 01.04 Standard
Release 5.0 23May 2008
Copyright© 2003-2008, Nor tel Networks
.