Datasheet

Table Of Contents
Section 9 I/O Ports
Rev. 2.00 Jul. 04, 2007 Page 160 of 692
REJ09B0309-0200
9.2 Port 3
Port 3 is an I/O port; its pins can also be configured to function as an SCI4 I/O pin, SCI3_2 I/O
pin, IIC2 I/O pin, and RTC output pin. Figure 9.2 shows the pin configuration.
P32/TXD32/SCL
P31/RXD32/SDA
P30/SCK32/TMOW/CLKOUT
P37/SO4
Port 3
P36/SI4
Figure 9.2 Port 3 Pin Configuration
Port 3 has the following registers.
Port data register 3 (PDR3)
Port control register 3 (PCR3)
Port pull-up control register 3 (PUCR3)
Port mode register 3 (PMR3)
9.2.1 Port Data Register 3 (PDR3)
PDR3 is a register that stores data of port 3.
Bit Bit Name
Initial
Value
R/W Description
7
6
P37
P36
0
0
R/W
R/W
If port 3 is read while PCR3 bits are set to 1, the values
stored in PDR3 are read, regardless of the actual pin
states. If port 3 is read while PCR3 bits are cleared to 0,
the pin states are read.
5 to 3 All 1 Reserved
These bits are always read as 1 and cannot be
modified.
2
1
0
P32
P31
P30
0
0
0
R/W
R/W
R/W
If port 3 is read while PCR3 bits are set to 1, the values
stored in PDR3 are read, regardless of the actual pin
states. If port 3 is read while PCR3 bits are cleared to 0,
the pin states are read.