8 - 5
program written to ROM (IC11). The microprocessor (IC1) outputs chip
select data using the address bus. IC2, IC6, IC7 or IC8 designates
memory IC and ports for the chip select data. The designated IC
supplies data to the microprocessor or any external device according to
the request made by the microprocessor. ROM (IC11) stores a program
that controls the microprocessor (IC1). EEPROM (IC9) stores memory
channel data and configuration data. RAM (IC10) temporarily stores
individual data. I/O ports (IC25, IC26, and IC27) monitor various
statuses (such as operation switches, remote input, and alarm), and send
control outputs (switching of audio signal, PLL circuit control, remote
output, etc.)
IC1
CPU
IC2,6,7 & 8
Chip Select
IC11
ROM
IC9
EEPROM
IC10
RAM
IC12,14…
Out port
IC22,25…
In port
IC32
Timer
CONTROL BUS
ADDRESS BUS
DATA BUS
Fig. 8.3 Control circuit Block diagram
