H8S2172 Datasheet, PDF (264/572 Pages) Renesas Technology Corp – Renesas 16-Bit Single-Chip Microcomputer H8S Family/H8S/2100 Series

8.3 Port 3
Port 3 is an 8-bit I/O port that also has other functions. The port 3 has the following registers.
• Port 3 data direction register (P3DDR)
• Port 3 data register (P3DR)
• Port 3 register (PORT3)
8.3.1 Port 3 Data Direction Register (P3DDR)
The individual bits of P3DDR specify input or output for the pins of port 3. P3DDR cannot be
read; if it is, an undefined value will be read.
Initial
Bit Bit Name Value
7
P37DDR 0
6
P36DDR 0
5
P35DDR 0
4
P34DDR 0
3
P33DDR 0
2
P32DDR 0
1
P31DDR 0
0
P30DDR 0
R/W Description
W
When a pin function is specified to a general purpose
W
I/O, setting this bit to 1 makes the corresponding port 3
pin an output pin, while clearing this bit to 0 makes the
W
pin an input pin.
W
W
W
W
W
8.3.2 Port 3 Data Register (P3DR)
P3DR stores output data for the port 3 pins.
Initial
Bit Bit Name Value
7
P37DR
0
6
P36DR
0
5
P35DR
0
4
P34DR
0
3
P33DR
0
2
P32DR
0
1
P31DR
0
0
P30DR
0
R/W Description
R/W Output data for a pin is stored when the pin function is
R/W ^{specified to a general purpose output.}
R/W
R/W
R/W
R/W
R/W
R/W
Rev. 2.00, 03/04, page 230 of 534