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RMU800A SERVICE MANUAL
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82
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Semiconductor Data
1. Voltage Supply: TA7805F (Display Unit IC501): Providing supply voltage.
2. Voltage Detector: R3111H421C(Display Unit IC502)
2-1.Pin Function
Pin No.
Name
I/O
Function
1 Vout
O
Reset.
2 GND
GND.
3 Vin
I
Supply
voltage.
3. Display CPU: UPD780112(Display Unit IC503)
3-1.Pin Function
Pin No.
Name
I/O
Function
1 AVref
+5V.
2 AVss
GND.
3 IC(vpp)
Internal
connected.
4 VDD
+5V.
5 Vss
GND.
6 X1
7 X2
Connection to crystal.
8 RESET
I CPU
reset.
9 XT1
+5V.
10 XT2
Not
used.
11 SHIFT
Beat
Shift.
12 Mute
MIC
Mute.
13 RSW3
Not
used.
14 RSW2
Not
used.
15
RSW0(DN)
I
Rotary SW0 (down).
16
RSW1(UP)
I
Rotary SW1 (up).
17 LCDBL
O LCD
backlight.
18
LCDCS
O
LCD control signal output.
19
LCDSOD
O
LCD data read.
20
LCDDAT
O
LCD data write.
21
LCDCLK
O
Clock output for LCD driver.
22 EVss
GND.
23 EVdd
+5V.
24
MICDAT
O
Serial data output for keypad MIC.
25 OUT1
Not
used.
26
RXD1
I
Serial data input.
27
TXD1
O
Serial data output.