Port Data Register 1 (Pdr1); Port Control Register 1 (Pcr1); Port Pull-Up Control Register 1 (Pucr1) - Hitachi H8/3664 Hardware Manual

9.2.3

Port Data Register 1 (PDR1)

Bit 7
P17
Initial value 0
Read/Write R/W
Note: * Bit 3 is reserved; it is always read as 1 and cannot be modified.
PDR1 is an 8-bit register that stores data for port 1 pins P17 to P14 and P12 to P10. If port 1 is
read while PCR1 bits are set to 1, the values stored in PDR1 are 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'08.
9.2.4

Port Control Register 1 (PCR1)

Bit
PCR17
Initial value
Read/Write
PCR1 is an 8-bit register for controlling whether each of the port 1 pins P17 to P14 and P12 to P10
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, which is always read as all 1s.
9.2.5

Port Pull-Up Control Register 1 (PUCR1)

Bit 7
PUCR17 PUCR16 PUCR15 PUCR14
Initial value 0
Read/Write R/W
Note: * Bit 3 is reserved; it is always read as 1 and cannot be modified.
6 5
P16 P15
0 0
R/W R/W
7 6
PCR16 PCR15
0 0
W W
6 5
0 0
R/W R/W
4
P14 —
0 1*
R/W —
5 4
PCR14
0 0
W W
4
—
0 1*
R/W —
3 2
P12
0
R/W R/W
3 2
— PCR12 PCR11
0 0
— W
3 2
PUCR12 PUCR11 PUCR10
0
R/W R/W
1 0
P11 P10
0 0
R/W
1 0
PCR10
0 0
W W
1 0
0 0
R/W
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