Datasheet

Section 9 I/O Ports
Rev.6.00 Mar. 18, 2009 Page 377 of 980
REJ09B0050-0600
9.10 Port C
Port C is an 8-bit I/O port that also has other functions. The port C has the following registers.
• Port C data direction register (PCDDR)
• Port C data register (PCDR)
• Port C register (PORTC)
• Port C MOS pull-up control register (PCPCR)
9.10.1 Port C Data Direction Register (PCDDR)
The individual bits of PCDDR specify input or output for the pins of port C.
PCDDR cannot be read; if it is, an undefined value will be read.
Bit Bit Name Initial Value R/W Description
7 PC7DDR 0 W
6 PC6DDR 0 W
5 PC5DDR 0 W
4 PC4DDR 0 W
3 PC3DDR 0 W
2 PC2DDR 0 W
1 PC1DDR 0 W
0 PC0DDR 0 W
• Modes 1 and 2
Port C pins are address outputs regardless of the
PCDDR settings.
• Modes 4 and 7 (when EXPE = 1)
Setting a PCDDR bit to 1 makes the corresponding
port C pin an address output, while clearing the bit
to 0 makes the pin an input port.
• Mode 7 (when EXPE = 0)
Port C is an I/O port, and its pin functions can be
switched with PCDDR.