122
Port Data Register 1 (PDR1)
Bit
7
6
5
4
3
2
1
0
P1
7
P1
6
P1
5
P1
4
P1
3
P1
2
P1
1
P1
0
Initial value
0
0
0
0
0
0
0
0
Read/Write
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
PDR1 is an 8-bit register that stores data for pins P1
7
to P1
0
of port 1. If port 1 is read while PCR1
bits are set to 1, the values stored in PDR1 are directly read, regardless of the actual pin states. If
port 1 is read while PCR1 bits are cleared to 0, the pin states are read.
Upon reset, PDR1 is initialized to H'00.
Port Control Register 1 (PCR1)
Bit
7
6
5
4
3
2
1
0
PCR1
7
PCR1
6
PCR1
5
PCR1
4
PCR1
3
PCR1
2
PCR1
1
PCR1
0
Initial value
0
0
0
0
0
0
0
0
Read/Write
W
W
W
W
W
W
W
W
PCR1 is an 8-bit register for controlling whether each of the port 1 pins P1
7
to P1
0
functions as an
input pin or output pin. Setting a PCR1 bit to 1 makes the corresponding pin an output pin, while
clearing the bit to 0 makes the pin an input pin. The settings in PCR1 and in PDR1 are valid only
when the corresponding pin is designated in PMR1 as a general I/O pin.
Upon reset, PCR1 is initialized to H'00.
PCR1 is a write-only register. All bits are read as 1.
Port Pull-Up Control Register 1 (PUCR1)
Bit
7
6
5
4
3
2
1
0
PUCR1
7
PUCR1
6
PUCR1
5
PUCR1
4
PUCR1
3
PUCR1
2
PUCR1
1
PUCR1
0
Initial value
0
0
0
0
0
0
0
0
Read/Write
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
PUCR1 controls whether the MOS pull-up of each port 1 pins P1
7
to P1
0
is on or off. When a
PCR1 bit is cleared to 0, setting the corresponding PUCR1 bit to 1 turns on the MOS pull-up for
the corresponding pin, while clearing the bit to 0 turns off the MOS pull-up.
Upon reset, PUCR1 is initialized to H'00.
