Carrier Interface - Nortel Enterprise 1000 Reference Manual

TS16 microprocessor
The functions of this microprocessor include:
• receiving signaling messages supplied by the DS-30X microprocessor,
decoding these messages, and taking subsequent actions
• transmitting messages to the DS-30X microprocessor
• handling PPM
• updating the TS16 select RAM and TS16 data RAM
• providing outpulsing
• receive data from the change-of-state microprocessor
• transmitting AIS for CNET (France) application
Change-of-state microprocessor
The functions of this processor are:
• detecting a valid change of state in TS16.
• when a valid change has been found, passing the new ABCD bits to the
TS16 microprocessor, along with five bits to indicate the associated
channel.

Carrier interface

Tx Direction
The HDB3 encoded multiplexer output is sent to the output selector, which
selects the PCM/Data output or the looped around far end data. The HDB3 is
converted from digital to AMI and sent to the carrier. A transformer provides
isolation and impedance matching (75 ohms or 120 ohms).
Rx Direction
The AMI data of the carrier is converted to digital and fed to the input selector
as well as the output selector for far end loopback. Clock recovery circuitry
within the receiving device extracts the 2.0 MHz clock. This clock is used to
generate the frame and multiframe count and is sent to the clock controller as
a reference.
Succession Communication Server for Enterprise 1000 Circuit Card Reference Guide
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