Renesas H8/3847R Series Hardware Manual page 265

2. Port Control Register 4 (PCR4)
Bit 7
—
Initial value 1
Read/Write —
PCR4 is an 8-bit register for controlling whether each of port 4 pins P4
input pin or output pin. Setting a PCR4 bit to 1 makes the corresponding pin an output pin, while
clearing the bit to 0 makes the pin an input pin. PCR4 and PDR4 settings are valid when the
corresponding pins are designated for general-purpose input/output by SCR3-2.
Upon reset, PCR4 is initialized to H'F8.
PCR4 is a write-only register, which always reads all 1s.
6 5 4
— — —
1 1 1
— — —
3 2
— PCR4 PCR4
2
1 0
— W
to P4
2 0
Rev. 6.00 Aug 04, 2006 page 227 of 680
Section 8 I/O Ports
1 0
PCR4
1 0
0 0
W W
functions as an
REJ09B0145-0600