Datasheet

Table Of Contents
Section 9 I/O Ports
Rev. 2.00 Jul. 04, 2007 Page 166 of 692
REJ09B0309-0200
9.3 Port 4
Port 4 is an I/O port; its pins can also be configured to function as SCI3_1 I/O pins and timer F I/O
pins. Figure 9.3 shows its pin configuration.
P42/TXD31/IrTXD/TMOFH
Port 4
P41/RXD31/IrRXD/TMOFL
P40/SCK31/TMIF
Figure 9.3 Port 4 Pin Configuration
Port 4 has the following registers.
Port data register 4 (PDR4)
Port control register 4 (PCR4)
Port mode register 4 (PMR4)
9.3.1 Port Data Register 4 (PDR4)
PDR4 is a register that stores data of port 4.
Bit Bit Name
Initial
Value
R/W Description
7 to 3 All 1 Reserved
These bits are always read as 1 and cannot be
modified.
2
1
0
P42
P41
P40
0
0
0
R/W
R/W
R/W
If port 4 is read while PCR4 bits are set to 1, the values
stored in PDR4 are read, regardless of the actual pin
states. If port 4 is read while PCR4 bits are cleared to 0,
the pin states are read.