Description Of Lsi - Sharp R-1750 Service Manual

R-1750
R-1751
R-1752
R-1754
LSI(IZA958DR)
The I/O signal of the LSI(IZA958DR) is detailed in the following table.
Pin No. Signal
1 TIOCA2 OUT
2 A20 OUT
3 Vcc
4 TMO0 OUT
5 PB1
6 PB2
7 PB3
8 PB4
9 PB5
10 PB6 OUT
11 PB7 OUT
12 RESO OUT
13 Vss
14 TxD0 OUT
15 P91 OUT
16 RxD0 OUT
17 P93 OUT
18 P94 OUT
19 P95 OUT
20 P40 OUT

DESCRIPTION OF LSI

I/O
Power level data output signal for inverter unit.
The power level will be decided by the time ratio
of T1 and T2.
Terminal not used.
IN Power source voltage : +5.0V.
The power source voltage to drive LSI is input to Vcc terminal. Connected to Vcc.
Signal to sound buzzer.
A: key touch sound (short beep). B: Completion sound (melody or long beep).
IN Signal coming from touch key.
When either G11 line on key matrix is touched, a corresponding signal out of P93, P94,
P95, P40, P41, P42, P43 and P44 will be input into PB1. When no key is touched, the
signal is held at "H" level.
IN Signal similar to PB1.
When either G12 line on key matrix is touched, a corresponding signal will be input into PB2.
IN Signal similar to PB1.
When either G13 line on key matrix is touched, a corresponding signal will be input into PB3.
IN Signal similar to PB1.
When either G6 line on key matrix is touched, a corresponding signal will be input into PB4.
IN Signal similar to PB1.
When either G5 line on key matrix is touched, a corresponding signal will be input into PB5.
Terminal not used. Connected to test point.
Turntable motor driving signal.
To turn on and off relay(RY2). "H" level: During
Turntable On. "L" level: During Turntable OFF or
during the oven is off condition.
Terminal not used.
IN Power source voltage: GND(0V).
The power source voltage to drive LSI is input to Vss terminal.
Data signal is output to a memory IC (IC4).
Clock signal is output to a memory IC (IC4).
Oven lamp, fan motor and stirrer motor driving signal
To turn on and off shut off relay (RY1). The
square waveform voltage is delivered to the
RY1 driving circuit.
Key strobe signal.
Signal applied to key unit section. A pulse signal is input to PB1-PB5 terminal while one
of G1 line keys on key matrix is touched.
Key strobe signal.
Signal applied to key unit section. A pulse signal is input to PB1-PB5 terminal while one
of G2 line keys on key matrix is touched.
Key strobe signal.
Signal applied to key unit section. A pulse signal is input to PB1-PB5 terminal while one
of G3 line keys on key matrix is touched.
Key strobe signal.
Signal applied to key unit section. A pulse signal is input to PB1-PB5 terminal while one
of G14 line keys on key matrix is touched.
Description
28
16.7 msec.
H : +5V
L : GND
T1 T2
H : +5V
ON
L : GND
OFF
16.7 msec.
H : +5V
L : GND
During cooking