HD64336900G Datasheet, PDF (144/408 Pages) Renesas Technology Corp – 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Tiny Series

9.2.2 Port Data Register 2 (PDR2)
PDR2 is a general I/O port data register of port 2.
Initial
Bit
Bit Name Value R/W Description
7 to 3 
All 1

Reserved
These bits are always read as 1.
2
P22
0
R/W These bits store output data for port 2 pins.
1
P21
0
0
P20
0
R/W If PDR2 is read while PCR2 bits are set to 1, the value
R/W
stored in PDR2 is read. If PDR2 is read while PCR2 bits
are cleared to 0, the pin states are read regardless of the
value stored in PDR2.
9.2.3 Pin Functions
The correspondence between the register specification and the port functions is shown below.
• P22/TXD pin
Register PMR1
Bit Name TXD
Setting
0
value
1
[Legend]
X: Don't care
PCR2
PCR22
0
1
X
Pin Function
P22 input pin
P22 output pin
TXD output pin
• P21/RXD pin
Register SCR3
Bit Name RE
Setting
0
value
1
[Legend]
X: Don't care
PCR2
PCR21
0
1
X
Pin Function
P21 input pin
P21 output pin
RXD input pin
Rev. 1.00, 11/03, page 116 of 376