User's Manual

68P80801H45-1 1/20/2002 19
EBTS System Manual - Vol 2 Base Radio Controllers
900 MHz QUAD Channel Base Radio Controller
Table 10 900 MHz QUAD Channel BR Controller Circuitry
Circuit Description
Host Microprocessor Contains integrated circuits that comprise the central controller
of the BRC and station
Non-Volatile Memory Consists of:
• FLASH containing the station operating software
• EEPROM containing the station codeplug data
Volatile Memory Contains SDRAM to store station software used to execute
commands.
Ethernet Interface Provides the BRC with a 10Base2 Ethernet communication port
to network both control and compressed voice data
RS-232 Interface Provides the BRC with an RS-232 serial interface
Digital Signal Processors Performs high-speed modulation/demodulation of
compressed audio and signaling data
TISIC Contains integrated circuits that provide timing reference
signals for the station
TX Reclock Contains integrated circuits that provide highly stable,
reclocked transmit signals and peripheral transmit logic
RX DSP SPI Contains integrated circuits that provide DSP SPI capability
and peripheral receive logic
Station Reference Circuitry Generates the 16.8 MHz and 48 MHz reference signals used
throughout the station
Input Ports Contains 16 signal input ports that receive miscellaneous
inputs from the BR
Output Ports Contains 40 signal output ports, providing a path for sending
miscellaneous control signals to circuits throughout the BR
Remote Station Shutdown Provides software control to cycle power on the BR