h8s-2649 Renesas Electronics Corporation., h8s-2649 Datasheet - Page 226

• Manufacturer Part Number: h8s-2649
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2600 Series
• Manufacturer: Renesas Electronics Corporation.

Section 9 I/O Ports
9.3
Port 3 is an 8-bit I/O port. Port 3 pins also function as SCI I/O pins and external interrupt input
pins. All of the port 3 pin functions have the same operating mode.
• Port 3 data direction register (P3DDR)
• Port 3 data register (P3DR)
• Port 3 register (PORT3)
• Port 3 open-drain control register (PORT3)
9.3.1
P3DDR is a write-only register, the individual bits of which specify input or output for the pins of
port 3. P3DDR cannot be read; if it is, an undefined value will be read.
Rev. 2.00 Dec. 05, 2005 Page 188 of 724
REJ09B0200-0200
Bit
7
6
5
4
3
2
1
0
Port 3
Port 3 Data Direction Register (P3DDR)
Bit Name
P37DDR
P36DDR
P35DDR
P34DDR
P33DDR
P32DDR
P31DDR
P30DDR
Initial
Value
0
0
0
0
0
0
0
0
R/W
W
W
W
W
W
W
W
W
Description
Setting a P3DDR bit to 1 makes the corresponding port
3 pin an output pin, while clearing the bit to 0 makes the
pin an input pin.