HD6433935 Hitachi, HD6433935 Datasheet - Page 183

• Manufacturer Part Number: HD6433935
• Description: 8-Bit MICROCONTROLLER
• Manufacturer: Hitachi

1. Port data register 9 (PDR9)
PDR9 is an 8-bit register that stores data for port 9 pins P9
bits are set to 1, the values stored in PDR9 are read, regardless of the actual pin states. If port 9 is
read while PCR9 bits are cleared to 0, the pin states are read.
Upon reset, PDR9 is initialized to H'F0.
2. Port control register 9 (PCR9)
PCR9 is an 8-bit register for controlling whether each of the port 9 pins P9
input pin or output pin. Setting a PCR9 bit to 1 makes the corresponding pin an output pin, while
clearing the bit to 0 makes the pin an input pin.
Upon reset, PCR9 is initialized to H'F0.
PCR9 is a write-only register, which is always read as all 1s.
Bit
Initial value
Read/Write
Bit
Initial value
Read/Write
—
—
—
—
7
0
7
1
—
—
—
—
6
0
6
1
—
—
—
—
5
0
5
1
—
—
—
—
4
0
4
1
PCR9
3
R/W
P9
to P9
W
3
0
3
0
3
3
0
. If port 9 is read while PCR9
PCR9
R/W
P9
W
2
0
2
0
2
2
3
to P9
PCR9
R/W
P9
W
1
0
1
0
0
functions as an
1
1
PCR9
R/W
P9
W
0
0
0
0
0
0
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