Port B; Port B Data Direction Register (Pbddr) - Renesas H8S Series Hardware Manual

9.5

Port B

Port B is an 8-bit I/O port that also has other functions. Port B has the following registers. For
details on register addresses and register states during each processing, refer to appendix A, On-
Chip I/O Register.

• Port B data direction register (PBDDR)

• Port B data register (PBDR)
• Port B register (PORTB)
• Port B pull-up MOS control register (PBPCR)
• Port B open-drain control register (PBODR)
9.5.1 Port B Data Direction Register (PBDDR)
PBDDR is an 8-bit write-only register, the individual bits of which specify whether the pins of
port B are used for input or output.
PBDDR cannot be read; if it is, an undefined value will be read.
Bit Bit Name
7 PB7DDR
6 PB6DDR
5 PB5DDR
4 PB4DDR
3 PB3DDR
2 PB2DDR
1 PB1DDR
0 PB0DDR
Initial Value R/W
0 W
0 W
0 W
0 W
0 W
0 W
0 W
0 W
Description
When a pin is specified as a general purpose I/O
port, setting this bit to 1 makes the corresponding
port 1 pin an output pin. Clearing this bit to 0 makes
the pin an input pin.
Rev. 6.00 Mar 15, 2006 page 141 of 570
Section 9 I/O Ports
REJ09B0211-0600