Port3; Overview; Register Configuration - Hitachi H8S/2646 Hardware Manual

9.4 Port 3
9.4.1

Overview

Port 3 is an 8-bit I/O port. Port 3 is a multi-purpose port for SCI I/O pins (TxD0, RxD0, SCK0,
TxD1, RxD1, SCK1), and external interrupt input pins (IRQ4, IRQ5). All of the port 3 pin
functions have the same operating mode. The configuration for each of the port 3 pins is shown in
figure. 9-3.
9.4.2

Register Configuration

Table 9-6 shows the configuration of port 3 registers.
Table 9-6 Port 3 Register Configuration
Name
Port 3 data direction register
Port 3 data register
Port 3 register
Port 3 open drain control register
Notes: * Lower 16 bits of the address.
242
Port 3 pins
P37 (I/O)
P36 (I/O)
(I/O) / SCK1 (I/O) / IRQ5 (input)
P35
P34 (I/O) / RxD1 (input)
Port 3
P33 (I/O) / TxD1 (output)
(I/O) / SCK0 (I/O) / IRQ4 (input)
P32
P31 (I/O) / RxD0 (input)
P30 (I/O) / TxD0 (output)
Figure 9-3 Port 3 Pin Functions
Abbreviation
P3DDR
P3DR

PORT3

P3ODR
R/W Initial Value
W H'00
R/W H'00
R Undefined
R/W H'00
Address*
H'FE32
H'FF02
H'FFB2
H'FE46