Nortel Networks Video Gaming Accessories 553-3001-211 Manual De Usuario
NT8D15 E&M Trunk card
Page 619 of 894
Functional description
The NT8D15 E&M Trunk card serves various transmission requirements.
The trunk circuits on the card can operate in either A-Law or µ-Law
companding modes. The mode of operation is set by service change entries.
The trunk circuits on the card can operate in either A-Law or µ-Law
companding modes. The mode of operation is set by service change entries.
shows a block diagram of the major functions
contained on the E&M trunk card. Each of these functions is discussed on the
following pages.
following pages.
Common features
The following features are common to all circuits on the NT8D15 E&M
Trunk card:
Trunk card:
•
Analog-to-digital and digital-to-analog conversion of transmission
signals.
signals.
•
Interfaces each of the four PCM signals to one DS30X timeslot in A10
format.
format.
•
Transmit and receive SSD signaling messages over a DS30X signaling
channel in A10 format.
channel in A10 format.
•
Ability to enable and disable individual ports or the entire card under
software control.
software control.
•
Provides outpulsing on the card. Make break ratios are defined in
software and down loaded at power up and by software commands.
software and down loaded at power up and by software commands.
•
Provides indication of card status from self-test diagnostics on faceplate
Light Emitting Diode (LED).
Light Emitting Diode (LED).
•
Supports loopback of PCM signals to DS30X for diagnostic purposes.
•
Card ID provided for auto configuration and determining serial number
and firmware level of card.
and firmware level of card.
•
Software controlled terminating impedance (600, 900, or 1200 ohm) two
and four-wire modes.
and four-wire modes.
•
Allows trunk type to be configured on a per port basis in software.
•
Software controlled 600 ohm balance impedance is provided.
•
Isolation of foreign potentials from transmission and signaling circuit.