Sharp AL-1000 Manual De Servicio página 84

AL-1000/1010
PIN No. Signal name
250 /CPUWR
251 /CPURD
252 GND
253 CPUCLK
254 GND
TEST
255
PORT1
256 /SCANST
(3) Reset circuit
This circuit detects ON/OFF of power to control start/stop of each circuit. The 5V voltage of the main PWB is detected by the reset
IC to generate the reset signal.
When the power voltage reaches the specified level, the circuit operations are started. Before the power voltage falls below the spec-
ified level, the circuit operations are stopped to prevent against malfunctions.
IN/OUT Connected to
IN CPU
IN CPU
Power
IN CPU
Power
AUTO SCAN
IN
TEST
IN CPU (I/O)
R265 R266
C190
C154
CPU write signal
CPU read signal
CPU system clock
High: Normal Low: Test
Scanner process start signal
IC108D
IC105
C155
Rest IC
C156
12-13
Description
To ASIC