Circuit Descriptions - Sharp AL-1550 Service Manual

2. Circuit descriptions

A. Main PWB (MCU)
(1) CPU signal table
The additional signal is as follows:
Pin No. Signal name
31
109
115
116
117
118
The signals of function change are as follows:
Pin No. Signal name
119 MRMT3
120 MRMT2
121 MRMT1
122 MRMT0
(2) ASIC signal table
The additional signal is as follows:
Pin No. Signal name
201
202
203
208
209 SMSEL
227
(3) Input signal table
The additional signals are as follows:
Signal name
SPF
2nd
In/Out
SPPD
SIN3
DMT3 Motor Output
DMT2 Motor Output
DMT1 Motor Output
DMT0 Motor Output
In/Out
Motor output
Motor output
Motor output
Motor output
In/Out
SGS Output
SRRC Output
SPUS Output
SPFS Output
Output
CPFS2 Output
SPID SPF paper entry detection signal
SDOD SPF open/close detection signal
SDSW SPF cover open/close detection signal
CED2 2nd cassette section cassette presence detection
PPD3 2nd cassette section paper transport detection
Input
Input
Mirror motor/SPF motor control signal
Mirror motor/SPF motor control signal
Mirror motor/SPF motor control signal
Mirror motor/SPF motor control signal
Connection
TR array IC
TR array IC
TR array IC
TR array IC
TR array IC
TR array IC
Descriptions
10 – 3
AL-1550
During operation
SPF paper transport detection signal
Sensor input 3
Duplex motor control signal
Duplex motor control signal
Duplex motor control signal
Duplex motor control signal
During operation
Descriptions
SPF gate solenoid control
signal. "H": Gate solenoid
ON (R-SPF only)
SPF resist roller clutch
control signal. "H": Clutch
ON (R-SPF only)
SPF pickup solenoid control
signal. "H": Solenoid ON
SPF paper feed solenoid
control signal. "H": Solenoid
ON (R-SPF only)
SPF/mirror motor relay
switch signal. "L": Mirror
motor, "H": SPF motor
2nd cassette paper feed
solenoid control signal. "H":
Solenoid ON