R8C/1A Group, R8C/1B Group
1. Overview
Rev.1.30
Dec 08, 2006
Page 12 of 315
REJ09B0252-0130
1.6
Pin Functions
Table 1.5 lists Pin Functions, Table 1.6 lists Pin Name Information by Pin Number of PLSP0020JB-A,
PRDP0020BA-A Packages and Table 1.7 lists Pin Name Information by Pin Number of PWQN0028KA-
B Package.
I: Input
O: Output
I/O: Input and output
Table 1.5
Pin Functions
Type
Symbol
I/O Type
Description
Power Supply Input VCC, VSS
I
Apply 2.7 V to 5.5 V to the VCC pin.
Apply 0 V to the VSS pin.
Analog Power
Supply Input
AVCC, AVSS
I
Power supply for the A/D converter
Connect a capacitor between AVCC and AVSS.
Reset Input
RESET
I
Input “L” on this pin resets the MCU.
MODE
MODE
I
Connect this pin to VCC via a resistor.
Main Clock Input
XIN
I
These pins are provided for main clock generation
circuit I/O. Connect a ceramic resonator or a
crystal oscillator between the XIN and XOUT pins.
To use an external clock, input it to the XIN pin
and leave the XOUT pin open.
Main Clock Output
XOUT
O
INT Interrupt
INT0, INT1, INT3
I
INT interrupt input pins
Key Input Interrupt
KI0 to KI3
I
Key input interrupt input pins
Timer X
CNTR0
I/O
Timer X I/O pin
CNTR0
O
Timer X output pin
Timer Z
TZOUT
O
Timer Z output pin
Timer C
TCIN
I
Timer C input pin
CMP0_0 to CMP0_2,
CMP1_0 to CMP1_2
O
Timer C output pins
Serial Interface
CLK0
I/O
Transfer clock I/O pin
RXD0, RXD1
I
Serial data input pins
TXD0, TXD1
O
Serial data output pins
Clock synchronous
serial I/O with chip
select (SSU)
SSI00, SSI01
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 Interface
SCL
I/O
Clock I/O pin
SDA
I/O
Data I/O pin
Reference Voltage
Input
VREF
I
Reference voltage input pin to A/D converter
A/D Converter
AN8 to AN11
I
Analog input pins to A/D converter
I/O Port
P1_0 to P1_7,
P3_3 to P3_5, P3_7,
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.
P1_0 to P1_3 also function as LED drive ports.
Input Port
P4_2, P4_6, P4_7
I
Input-only ports
