Datasheet

Rev.6.00 Oct.28.2004 page 301 of 1016
REJ09B0138-0600H
9.8 Port A
9.8.1 Overview
Port A is an 8-bit I/O port. Port A pins also function as address bus outputs and interrupt input pins (IRQ4 to IRQ7). The
pin functions change according to the operating mode.
Port A has a on-chip MOS input pull-up function that can be controlled by software. Pins PA
7
to PA
4
are schmitt-triggered
inputs.
Figure 9-7 shows the port A pin configuration.
PA
7
/A
23
/IRQ7
PA
6
/A
22
/IRQ6
PA
5
/A
21
/IRQ5
PA
4
/A
20
/IRQ4
PA
3
/A
19
PA
2
/A
18
PA
1
/A
17
PA
0
/A
16
PA
7
(input)/A
23
(output)/IRQ7 (input)
PA
6
(input)/A
22
(output)/IRQ6 (input)
PA
5
(input)/A
21
(output)/IRQ5 (input)
A
20
(output)
A
19
(output)
A
18
(output)
A
17
(output)
A
16
(output)
Note: * Modes 6 and 7 are provided in the on-chip ROM version only.
Port A pins
Pin functions in modes 4 and 5
Pin functions in mode 6*
PA
7
(I/O)/IRQ7 (input)
PA
6
(I/O)/IRQ6 (input)
PA
5
(I/O)/IRQ5 (input)
PA
4
(I/O)/IRQ4 (input)
PA
3
(I/O)
PA
2
(I/O)
PA
1
(I/O)
PA
0
(I/O)
Pin functions in mode 7*
PA
7
(input)/A
23
(output)/IRQ7 (input)
PA
6
(input)/A
22
(output)/IRQ6 (input)
PA
5
(input)/A
21
(output)/IRQ5 (input)
PA
4
(input)/A
20
(output)/IRQ4 (input)
PA
3
(input)/A
19
(output)
PA
2
(input)/A
18
(output)
PA
1
(input)/A
17
(output)
PA
0
(input)/A
16
(output)
Port A
Figure 9-7 Port A Pin Functions