HD6433937 Datasheet, PDF (183/521 Pages) Hitachi Semiconductor – Hardware Manual

1. Port data register 9 (PDR9)
Bit
7
6
5
4
3
2
1
0
—
—
—
—
P9₃
P9₂
P9₁
P9₀
Initial value
0
0
0
0
0
0
0
0
Read/Write
—
—
—
—
R/W
R/W
R/W
R/W
PDR9 is an 8-bit register that stores data for port 9 pins P9₃ to P9₀. If port 9 is read while PCR9
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)
Bit
7
6
5
—
—
—
Initial value
1
1
1
Read/Write
—
—
—
4
3
2
1
0
— PCR9₃ PCR9₂ PCR9₁ PCR9₀
1
0
0
0
0
—
W
W
W
W
PCR9 is an 8-bit register for controlling whether each of the port 9 pins P9₃ to P9₀ functions as an
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.
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