h8s-2172 Renesas Electronics Corporation., h8s-2172 Datasheet - Page 286

• Manufacturer Part Number: h8s-2172
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family H8s-2100 Series
• Manufacturer: Renesas Electronics Corporation.

• P80/D8
8.9
Port 9 is an 8-bit I/O port that also has other functions. The port 9 has the following registers.
• Port 9 data direction register (P9DDR)
• Port 9 data register (P9DR)
• Port 9 register (PORT9)
8.9.1
The individual bits of P9DDR specify input or output for the pins of port 9. P9DDR cannot be
read; if it is, an undefined value will be read.
Rev. 2.00, 03/04, page 254 of 534
EXPE
P80DDR
Pin function
Bit
7
6
5
4
3
2
1
0
The pin function is switched as shown below according to the combination of the P80DDR bit
and the EXPE bit in MDCR.
Bit Name
P97DDR
P96DDR
P95DDR
P94DDR
P93DDR
P92DDR
P91DDR
P90DDR
Port 9
Port 9 Data Direction Register (P9DDR)
Initial
Value
0
0
0
0
0
0
0
0
P80 input
R/W
W
W
W
W
W
W
W
W
0
Description
When a pin function is specified to a general purpose
I/O, setting this bit to 1 makes the corresponding port 9
pin an output pin, while clearing this bit to 0 makes the
pin an input pin.
0
P80 output
1
D8 I/O

1