Datasheet

Section 9 I/O Ports
Rev.6.00 Sep. 27, 2007 Page 374 of 1268
REJ09B0220-0600
9.4 Port 3
9.4.1 Overview
Port 3 is a 6-bit I/O port. Port 3 pins also function as SCI I/O pins (TxD
0
, RxD
0
, SCK
0
, TxD
1
,
RxD
1
, and SCK
1
). Port 3 pin functions are the same in all operating modes.
Figure 9.3 shows the port 3 pin configuration.
P3
5
(I/O) / SCK
1
(I/O)
P3
4
(I/O) / SCK
0
(I/O)
P3
3
(I/O) / RxD
1
(input)
P3
2
(I/O) / RxD
0
(input)
P3
1
(I/O) / TxD
1
(output)
P3
0
(I/O) / TxD
0
(output)
Port 3 pins
Port 3
Figure 9.3 Port 3 Pin Functions
9.4.2 Register Configuration
Table 9.6 shows the port 3 register configuration.
Table 9.6 Port 3 Registers
Name Abbreviation R/W Initial Value
*
2
Address
*
1
Port 3 data direction register P3DDR W H'00 H'FEB2
Port 3 data register P3DR R/W H'00 H'FF62
Port 3 register PORT3 R Undefined H'FF52
Port 3 open drain control register P3ODR R/W H'00 H'FF76
Notes: 1. Lower 16 bits of the address.
2. Value of bits 5 to 0.