r4f2426 Renesas Electronics Corporation., r4f2426 Datasheet - Page 616

• Manufacturer Part Number: r4f2426
• Description: 16-bit Single-chip Microcomputer H8s Family / H8s/2400 Series
• Manufacturer: Renesas Electronics Corporation.

Section 10 I/O Ports
10.9.1
The individual bits of PADDR specify input or output for the pins of port A. PADDR cannot be
read; if it is, an undefined value will be read.
Rev. 1.00 Sep. 19, 2008 Page 588 of 1270
REJ09B0466-0100
Bit
7
6
5
4
3
2
1
0
Bit Name
PA7DDR
PA6DDR
PA5DDR
PA4DDR
PA3DDR
PA2DDR
PA1DDR
PA0DDR
Port A Data Direction Register (PADDR)
Initial Value
0
0
0
0
0
0
0
0
R/W
W
W
W
W
W
W
W
W
Description
•
•
•
Modes 1 and 2
Pins PA4 to PA0 are address outputs.
For pins PA7 to PA5, when the corresponding bit
of A23E to A21E is set to 1, setting a PADDR bit
to 1 makes the corresponding pin an address
output, while clearing the bit to 0 makes the
corresponding pin an input port. Clearing one of
bits A23E to A21E to 0 makes the corresponding
pin an I/O port, and its function can be switched
with PADDR.
Modes 7 (when EXPE = 1) and 4
When the corresponding bit of A23E to A16E is
set to 1, setting a PADDR bit to 1 makes the
corresponding pin an address output, while
clearing the bit to 0 makes the corresponding pin
an input port. Clearing one of bits A23E to A16E
to 0 makes the corresponding pin an I/O port,
and its function can be switched with PADDR.
Mode 7 (when EXPE = 0)
Port A is an I/O port, and its pin functions can be
switched with PADDR.