Datasheet
Section 10 I/O Ports 
R01UH0310EJ0500 Rev. 5.00    Page 647 of 1384 
Sep 25, 2012     
H8S/2426, H8S/2426R, H8S/2424 Group 
10.12  Port D 
Port D is an 8-bit I/O port that also has other functions. Port D has the following registers. 
•  Port D data direction register (PDDDR) 
•  Port D data register (PDDR) 
•  Port D register (PORTD) 
•  Port D pull-up MOS control register (PDPCR) 
•  Port D open drain control register (PDODR) 
10.12.1  Port D Data Direction Register (PDDDR) 
The individual bits of PDDDR specify input or output for the pins of port D. PDDDR cannot be 
read; if it is, an undefined value will be read. 
Bit  Bit Name  Initial Value  R/W  Description 
7 PD7DDR 0  W 
6 PD6DDR 0  W 
5 PD5DDR 0  W 
4 PD4DDR 0  W 
3 PD3DDR 0  W 
2 PD2DDR 0  W 
1 PD1DDR 0  W 
0 PD0DDR 0  W 
•  Modes 1, 2, and 4 Modes 3 and 7 (EXPE = 1)
Port D is automatically designated for data 
input/output. 
•  Modes 3 and 7 (EXPE = 0) 
Port D is an I/O port, and its pin functions can be 
switched with PDDDR. 










