HD6413008F RENESAS [Renesas Technology Corp], HD6413008F Datasheet - Page 201

• Manufacturer Part Number: HD6413008F
• Description: Renesas 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Series
• Manufacturer: RENESAS [Renesas Technology Corp]

7.6.2
Table 7.9 summarizes the registers of port 9.
Table 7.9
Address*
H'EE008
H'FFFD8
Note:
Port 9 Data Direction Register (P9DDR): P9DDR is an 8-bit write-only register that can select
input or output for each pin in port 9.
Bits 7 and 6 are reserved. They are fixed at 1, and cannot be modified.
When port 9 functions as an input/output port, a pin in port 9 becomes an output port if the
corresponding P9DDR bit is set to 1, and an input port if this bit is cleared to 0. For the method of
selecting the pin functions, see table 7.10.
P9DDR is a write-only register. Its value cannot be read. All bits return 1 when read.
P9DDR is initialized to H'C0 by a reset and in hardware standby mode. In software standby mode
it retains its previous setting. Therefore, if a transition is made to software standby mode while
port 9 is functioning as an input/output port and a P9DDR bit is set to 1, the corresponding pin
maintains its output state.
Bit
Initial value
Read/Write
* Lower 20 bits of the address in advanced mode.
Register Descriptions
Port 9 Registers
Name
Port 9 data direction register
Port 9 data register
Reserved bits
⎯
⎯
7
1
⎯
⎯
6
1
P9 DDR
5
W
5
0
P9 DDR
Abbreviation
P9DDR
P9DR
4
W
4
0
Port 9 data direction 5 to 0
These bits select input or
output for port 9 pins
Rev.4.00 Aug. 20, 2007 Page 157 of 638
P9 DDR
3
W
3
0
P9 DDR
R/W
W
R/W
2
W
2
0
P9 DDR
Initial Value
H'C0
H'C0
REJ09B0395-0400
1
W
1
0
7. I/O Ports
P9 DDR
0
W
0
0