Datasheet

Section 10 I/O Ports
Page 588 of 1408 R01UH0309EJ0500 Rev. 5.00
Sep 24, 2012
H8S/2456, H8S/2456R, H8S/2454 Group
10.7 Port 8
Port 8 is a 6-bit I/O port that also has other functions. Port 8 has the following registers. For the
port function control registers, refer to section 10.18, Port Function Control Registers.
• Port 8 data direction register (P8DDR)
• Port 8 data register (P8DR)
• Port 8 register (PORT8)
• Port 8 open drain control register (P8ODR)
• Port function control register 3 (PFCR3)
10.7.1 Port 8 Data Direction Register (P8DDR)
The individual bits of P8DDR specify input or output for the pins of port 8. P8DDR cannot be
read; if it is, an undefined value will be read.
Bit Bit Name Initial Value R/W Description
7, 6 ⎯ All 0 ⎯ Reserved
5 P85DDR 0 W
4 P84DDR 0 W
3 P83DDR 0 W
2 P82DDR 0 W
1 P81DDR 0 W
0 P80DDR 0 W
When a pin function is specified as a general
purpose I/O, setting this bit to 1 makes the
corresponding pin an output port, while clearing this
bit to 0 makes the corresponding pin an input port.
Bits 4, 2, and 0 are reserved in the H8S/2454
Group.