Instruction manual

FUNCTIONAL DESCRIPTION
TDM
BUS
LEADS
CIRCUIT
PACK
ADDRESS
LEADS
Figure 3-20. Pooled Modem (TN758)
● Common Circuitry
The Pooled Modem contains the same common circuitry as port CPs.
● Conversion Resources
The two conversion resources (port circuits) are identical and each contain the
following:
— Microprocessor
— Transmit and Receive I-channel Controller (TRIC)
— Universal Synchronous/Asynchronous Receiver and Transmitter (USART)
— Data USART Clock (DUCK)
— Digital Signal Processor (DSP).
The microprocessor controls an on-board data module and modem.
This
microprocessor communicates with the port circuit microprocessor over a serial
control channel.
This channel allows the on-board microprocessor to send
messages to the port circuit microprocessor specifying call startup information,
option settings,
information requests,
various test modes, and call termination
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