— 2 —
Pin No.
Signal
I / O
Function
1~7, 64
P00~P13
Out
Common signal for keyboard
8~12
P20~P22, P32, P33
In
Key signal from keyboard
13
IRQ
In
Timing pulse signal from printer
14
DEBIN
In
Reset pulse (Not used)
15
IRQCNT
In
Auxiliary timing (VDD)
16
P40
Out
Motor control signal
17
P41
Out
Ribbon shift signal for printer
18~30
P42, P43, P50~P53,
Out
Character selective signal for printer
P70~P73, P80~P82
31, 32
P83, P90
Out
Segment signal for display,
Character selective signal for printer
33~39
P91~P93
Out
Common signal for slide switch,
PA0~PA3
Segment signal for display
40
P60
In
Input port (VDD)
41~43
P61~P63
In
Signal from slide switch
44~56
PB0~PB3,
Out
Digit signal for display
PC0~PC3,
PD0~PD3,
PE0
57
VPP
In
GND terminal
58
VDD
In
VDD terminal (+33V)
59, 60
OSC1, OSC2
I/O
Clock signal for CPU
61
VSS
In
VSS terminal (+28V)
62
SYNC
—
Not used
63
RST
In
Signal from slide switch, Reset signal
3. CPU (MN158418YCY) PIN FUNCTION
