Station Control Module Operation - Motorola MTR2000 Installation And Operation Manual

Description

Station Control Module Operation

8
Introduction
The Station Control Module (SCM) is the microprocessor-based controller for the sta-
tion. Major components include an MC68356 microprocessor, which combines a
68302 Integrated Multiprotocol Processor (IMP) with a 56002 Digital Signal Processor
(DSP), a DSP ASIC device, and several Codec filter devices.
Station Control Module Operation
The MC68356 forms the heart of the SCM. The 68302 portion is the Host Micropro-
cessor (µP), which serves as the controller for the SCM and operates from station soft-
ware stored in FLASH memory. This software determines the system capabilities of
the station. The Host µP communicates with the station modules and the SCM cir-
cuitry via address and data buses, three SCI (Serial Communication Interface) ports,
and an SPI bus.
The DSP portion of the MC68356, with the support of the DSP ASIC, perform the nec-
essary digital processing for the station audio and data signals. The DSP circuitry in-
terfaces with the Receiver Module (receive audio), the Exciter Module (VCO
modulation signal), the Wireline Interface Board (wireline audio), and external audio
devices (microphone and speaker).
The 2.1 MHz Reference Oscillator generates the reference signal used by the Receiver
and Exciter Modules.
68P81096E36-H
06/28/05