HD6432646 Hitachi, HD6432646 Datasheet - Page 257

• Manufacturer Part Number: HD6432646
• Description: (HD64F264x Series) 16-Bit Microcomputer
• Manufacturer: Hitachi

Port 1 Register (PORT1)
Note: * Determined by state of pins P17 to P10.
PORT1 is an 8-bit read-only register that shows the pin states. It cannot be written to. Writing of
output data for the port 1 pins (P17 to P10) must always be performed on P1DR.
If a port 1 read is performed while P1DDR bits are set to 1, the P1DR values are read. If a port 1
read is performed while P1DDR bits are cleared to 0, the pin states are read.
After a reset and in hardware standby mode, PORT1 contents are determined by the pin states, as
P1DDR and P1DR are initialized. PORT1 retains its prior state in software standby mode.
Bit
Initial value :
R/W
:
:
P17
—*
7
R
P16
—*
6
R
P15
—*
5
R
P14
—*
4
R
P13
—*
3
R
P12
—*
2
R
P11
—*
1
R
P10
—*
0
R
223