HD64F3642AHV Datasheet, PDF (194/551 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Section 8 I/O Ports
PDR1 is an 8-bit register that stores data for port 1 pins P1₇ through P1₄ and 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'00.
Port Control Register 1 (PCR1)
Bit
7
6
5
4
3
2
1
0
PCR17 PCR16 PCR15 PCR14



PCR10
Initial value
0
0
0
0
0
0
0
0
Read/Write
W
W
W
W



W
PCR1 is an 8-bit register for controlling whether each of the port 1 pins P1₇ through P1₄ and 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.
Port Pull-Up Control Register 1 (PUCR1)
Bit
7
6
5
4
3
2
1
0
PUCR17 PUCR16 PUCR15 PUCR14 


PUCR10
Initial value
0
0
0
0
0^*
0^*
0^*
0
Read/Write
R/W
R/W
R/W
R/W



R/W
Note: * Bits 3 to 1 are reserved; they are always read as 0 and cannot be modified.
PUCR1 controls whether the MOS pull-up of each of the port 1 pins P1₇ through P1₄ and P1₀ 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.
Rev. 6.00 Sep 12, 2006 page 172 of 526
REJ09B0326-0600