h8s-2161b Renesas Electronics Corporation., h8s-2161b Datasheet - Page 233

• Manufacturer Part Number: h8s-2161b
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

8.4
Port 3 is an 8-bit I/O port. Port 3 pins also function as a bidirectional data bus, XBS bidirectional
data bus, and LPC input/output pins. Port 3 functions change according to the operating mode.
Port 3 has the following registers.
8.4.1
P3DDR specifies input or output for the pins of port 3 on a bit-by-bit basis.
Bit
7
6
5
4
3
2
1
0
Port 3 data direction register (P3DDR)
Port 3 data register (P3DR)
Port 3 pull-up MOS control register (P3PCR)
Bit Name
P37DDR
P36DDR
P35DDR
P34DDR
P33DDR
P32DDR
P31DDR
P30DDR
Port 3
Port 3 Data Direction Register (P3DDR)
Initial Value
0
0
0
0
0
0
0
0
R/W
W
W
W
W
W
W
W
W
Description
Modes 1, 2, and 3 (EXPE = 1)
The input/output direction specified by P3DDR is
ignored, and pins automatically function as data
I/O pins.
Modes 2 and 3 (EXPE = 0)
The corresponding port 3 pins are output ports
when P3DDR bits are set to 1, and input ports
when cleared to 0.
Rev. 3.00 Mar 21, 2006 page 179 of 788
Section 8 I/O Ports
REJ09B0300-0300