R8C/3MQ Group 1. Overview
R01DS0044EJ0200 Rev.2.00 Page 9 of 47
Jun 29, 2012
1.5 Pin Functions
Tables 1.6 and 1.7 list Pin Functions.
I: Input O: Output I/O: Input and output
Table 1.6 Pin Functions (1)
Item Pin Name I/O Type Description
Power supply input VCC, VSS1 — Apply 1.8 to 3.6 V to the VCC pin.
Apply 0 V to the VSS1 pin.
Reset input
RESET
I Input “L” on this pin resets the MCU.
MODE MODE I Connect this pin to VCC via a resistor.
XIN clock input XIN I These pins are provided for XIN clock oscillation circuit I/O.
Connect a crystal oscillator between the XIN and XOUT pins.
XIN clock output XOUT I/O
XCIN clock input XCIN I These pins are provided for XCIN clock oscillation circuit I/O.
Connect a crystal oscillator between the XCIN and XCOUT
pins.
XCIN clock output XCOUT O
INT
interrupt input INT0, INT1, INT3
I
INT
interrupt input pins.
INT0 is used as an input pin for timer RB and timer RC.
Key input interrupt
input
KI0
to KI7
I Key input interrupt input pins.
Timer RA TRAIO I/O Timer RA I/O pin.
TRAO O Timer RA output pin.
Timer RB TRBO O Timer RB output pin.
Timer RC TRCCLK I External clock input pin.
TRCTRG I External trigger input pin.
TRCIOA, TRCIOB,
TRCIOC, TRCIOD
I/O Timer RC I/O pins.
Timer RE TREO O Divided clock output pin.
Serial interface CLK0 I/O Transfer clock I/O pin.
RXD0 I Serial data input pin.
TXD0 O Serial data output pin.
SSU SSI I/O Data I/O pin.
SCS
I/O Chip-select signal I/O pin.
SSCK I/O Clock I/O pin.
SSO I/O Data I/O pin.
I
2
C bus
SCL I/O Clock I/O pin
SDA I/O Data I/O pin
I/O ports P0_4, P1_0 to P1_7,
P3_0, P3_1,
P3_3 to P3_5, P3_7,
P4_3 to P4_5
I/O CMOS I/O ports. Each port has an I/O select direction
register, allowing each pin in the port to be directed for input
or output individually.
Any port set to input can be set to use a pull-up resistor or not
by a program.
