Pin Description
Mitsubishi microcomputers
M16C / 62A Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
9
Pin Description
Signal name
Function
Pin name
I/O type
I/O port P5
Input/output
Input/output
Input/output
Input/output
Input/output
Input/output
Input
Input/output
Input/output
I/O port P6
I/O port P7
I/O port P8
I/O port P8
5
I/O port P9
I/O port P10
P5
0
to P5
7
P6
0
to P6
7
P7
0
to P7
7
P8
0
to P8
4
,
P8
6
,
P8
7
,
P8
5
P9
0
to P9
7
P10
0
to P10
This is an 8-bit I/O port equivalent to P0. In single-chip mode, P5
7
in
this port outputs a divide-by-8 or divide-by-32 clock of X
IN
or a clock of
the same frequency as X
CIN
as selected by software.
Output
Output
Output
Output
Output
Input
Output
Input
This is an 8-bit I/O port equivalent to P0. When used for input in single-
chip, memory expansion, and microprocessor modes, the port can be
set to have or not have a pull-up resistor in units of four bits by
software. Pins in this port also function as UART0 and UART1 I/O pins
as selected by software.
This is an 8-bit I/O port equivalent to P6 (P7
0
and P7
1
are N channel
open-drain output). Pins in this port also function as timer A
0
–A
3
,
timer B5 or UART2 I/O pins as selected by software.
This is an 8-bit I/O port equivalent to P6. Pins in this port also function
as SI/O3, 4 I/O pins, Timer B0–B4 input pins, D-A converter output pins,
A-D converter extended input pins, or A-D trigger input pins as selected
by software.
This is an 8-bit I/O port equivalent to P6. Pins in this port also function
as A-D converter input pins. Furthermore, P10
4
–P10
7
also function as
input pins for the key input interrupt function.
WRL / WR,
WRH / BHE,
RD,
BCLK,
HLDA,
HOLD,
ALE,
RDY
Output WRL, WRH (WR and BHE), RD, BCLK, HLDA, and ALE
signals. WRL and WRH, and BHE and WR can be switched using
software control.
WRL, WRH, and RD selected
With a 16-bit external data bus, data is written to even addresses
when the WRL signal is “L” and to the odd addresses when the WRH
signal is “L”. Data is read when RD is “L”.
WR, BHE, and RD selected
Data is written when WR is “L”. Data is read when RD is “L”. Odd
addresses are accessed when BHE is “L”. Use this mode when using
an 8-bit external data bus.
While the input level at the HOLD pin is “L”, the microcomputer is
placed in the hold state. While in the hold state, HLDA outputs a “L”
level. ALE is used to latch the address. While the input level of the
RDY pin is “L”, the microcomputer is in the ready state.
P8
0
to P8
4
, P8
6
, and P8
7
are I/O ports with the same functions as P6.
Using software, they can be made to function as the I/O pins for timer
A4 and the input pins for external interrupts. P8
6
and P8
7
can be set
using software to function as the I/O pins for a sub clock generation
circuit. In this case, connect a quartz oscillator between P8
6
(X
COUT
pin) and P8
7
(X
CIN
pin). P8
5
is an input-only port that also functions
for NMI. The NMI interrupt is generated when the input at this pin
changes from “H” to “L”. The NMI function cannot be cancelled using
software. The pull-up cannot be set for this pin.