Datasheet

Section 9 I/O Ports
Rev. 3.00 Sep. 10, 2007 Page 165 of 528
REJ09B0216-0300
9.9 Port C
Port C is a general I/O port also functioning as an external oscillation pin and clock output pin.
Each pin of the port C is shown in figure 9.9. The register setting of CKCSR has priority for
functions of the pins for both uses.
PC1/OSC2/CLKOUT
PC0/OSC1
Port C
Figure 9.9 Port C Pin Configuration
Port C has the following registers.
• Port control register C (PCRC)
• Port data register C (PDRC)
9.9.1 Port Control Register C (PCRC)
PCRC selects inputs/outputs in bit units for pins to be used as general I/O ports of port C.
Bit Bit Name
Initial
Value
R/W Description
7 to 2    Reserved
1
0
PCRC1
PCRC0
0
0
W
W
When each of the port C pins, PC1 and PC0, functions as
an general I/O port, setting a PCRC bit to 1 makes the
corresponding pin an output port, while clearing the bit to
0 makes the pin an input port.