Renesas SH7781 用户手册
28. General Purpose I/O Ports (GPIO)
Rev.1.00 Jan. 10, 2008 Page 1433 of 1658
REJ09B0261-0100
28.2.32
Port R Data Register (PRDR)
PRDR is an 8-bit readable/writable register that stores port R data.
0
1
2
3
4
5
6
7
0
0
0
0
0
0
0
0
PR0DT
PR1DT
PR2DT
PR3DT
—
—
—
—
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Bit:
Initial value:
R/W:
Bit Bit
Name
Initial
value R/W Description
value R/W Description
7 to 4
⎯ All
0
R/W
Reserved
These bits are always read as 0, and the write value
should always be 0.
should always be 0.
3 PR3DT
0* R/W
2 PR2DT
0* R/W
1 PR1DT
0* R/W
0 PR0DT
0* R/W
These bits store output data of a pin which is used as a
general-purpose output port. When the pin functions as
a general-purpose output port, reading the port will read
out the value of the corresponding bit of this register.
general-purpose output port. When the pin functions as
a general-purpose output port, reading the port will read
out the value of the corresponding bit of this register.
When the pin functions as a general-purpose input port,
reading the port will read out the status of the
corresponding pin.
reading the port will read out the status of the
corresponding pin.
Note: * When the bus mode is set to DU by the bus mode pins (MODE11 and MODE12), the
pin is initially used as a general-purpose input, and the pin status is read from this
register.
register.