Datasheet
Section 10 I/O Ports 
Page 592 of 1384    R01UH0310EJ0500 Rev. 5.00 
 Sep 25, 2012 
H8S/2426, H8S/2426R, H8S/2424 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/2424 
Group. 










