Port 9; Port 9 Data Direction Register (P9Ddr) - Renesas H8S/2437 Hardware Manual

7.10

Port 9

Port 9 is an 8-bit I/O port. Port 9 pins also function as bus control I/O pins, system clock output
pins, and TPU I/O pins. Port 9 functions change according to the operating mode.
Port 9 has the following registers.

• Port 9 data direction register (P9DDR)

• Port 9 data register (P9DR)
• Port 9 register (PORT9)
• Port function control register (PFCR)
7.10.1 Port 9 Data Direction Register (P9DDR)
The individual bits in P9DDR specify input or output for the pins of port 9. The read value is
undefined.
Bit Bit Name
7 P97DDR
6 P96DDR
5 P95DDR
4 P94DDR
3 P93DDR
2 P92DDR
1 P91DDR
0 P90DDR
Initial Value R/W
0 W
0 W
0 W
0 W
0 W
0 W
0 W
0 W
Description
If port 9 pins are specified for use as the general
I/O port, the corresponding port 9 pins are output
ports when the P9DDR bits are set to 1, and input
ports when cleared to 0.
When this bit is set to 1, the corresponding port 9
pin is the system clock output pin (φ), and as a
general input port when cleared to 0.
If port 9 pins are specified for use as the general
I/O port, the corresponding port 9 pins are output
ports when the P9DDR bits are set to 1, and input
ports when cleared to 0.
Rev. 1.00, 09/03, page 189 of 704