4
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
MITSUBISHI MICROCOMPUTERS
38C8 Group
Apply voltage of 4.0–5.5 V to VCC, and 0 V to VSS. (at high-speed mode)
Reset input pin for active “L.”
Input and output pins for the main clock generating circuit.
Feedback resistor is built in between XIN pin and XOUT pin.
Connect a ceramic resonator or a quartz-crystal oscillator between the XIN and XOUT pins to set the
oscillation frequency.
If an external clock is used, connect the clock source to the XIN pin and leave the XOUT pin open.
This pin determines the oscillation between XIN and XOUT. The oscillation method can be selected from
either by an oscillator or by a resistor.
Input and output pins for sub-clock generating circuit. (Connect a quartz-crystal oscillator between the
XCIN and XCOUT pins to set the oscillation frequency. The clock generated the externals cannot be input
directly.)
Reference voltage input pin for LCD.
The input voltage to this pin is boosted threefold by voltage multiplier.
LCD drive power source pins.
LCD common output pins.
LCD segment/common output pins.
LCD segment output pins.
8-bit I/O port.
CMOS compatible input level.
CMOS 3-state output structure.
4-bit I/O port.
CMOS compatible input level.
CMOS 3-state output structure.
1-bit input port.
CMOS compatible input level.
7-bit I/O port.
CMOS compatible input level.
CMOS 3-state output structure.
I/O direction register allows each pin to be individually
programmed as either input or output.
External capacitor connect pins for a voltage multiplier of LCD.
Non-function pins.
Leave the VSS (NC) pin open.
A-D converter analog input pin
Key-on wake-up interrupt input pin
A-D converter analog input pin
External interrupt pin
A-D trigger input pin
Timer function I/O pin
Serial I/O I/O pin
Pin
VCC, VSS
RESET
XIN
XOUT
OSCSEL
XCIN
XCOUT
VLIN
VL1 – VL5
COM0 –
COM15
SEG0/COM16–
SEG7/COM23,
SEG60COM31–
SEG67/COM24
SEG8–SEG59
P00–P07
P14–P17
P10/AIN4–
P13/AIN7
P20–P27
P30/AIN0 –
P33/AIN3
P40/INT0
P41/INT1/ADT
P42/CNTR0/
BEEP+,
P43/CNTR1/
BEEP-
P44/RxD,
P45/TxD,
P46/SCLK,
P47/SRDY
C1,
C2,
C3
VSS (NC), NC
Name
Power source
Reset input
Clock input
Clock output
RC oscillation
select
Sub-clock input
Sub-clock output
Power source
input for LCD
LCD power
source
Common output
Segment output/
Common output
Segment output
I/O port P0
I/O port P1
I/O port P2
I/O port P3
Input port P4
I/O port P4
Voltage multiplier
Function except a port function
PIN DESCRIPTION
Table 1 Pin description
Function