Datasheet

Section 9 I/O Ports
Rev.6.00 Sep. 27, 2007 Page 402 of 1268
REJ09B0220-0600
Pin Selection Method and Pin Functions
PA
4
/A
20
/IRQ
4
The pin function is switched as shown below according to the combination of
the operating mode and bits A20E and PA4DDR.
Operating
mode
Modes 4 and 5 Mode 6 Mode 7
A20E 0 1 0 1 —
PA4DDR 0 1 — 0 1 0 1 0 1
Pin function Setting
pro-
hibited
PA
4
output
pin
A
20
output
pin
PA
4
input
pin
PA
4
output
pin
PA
4
input
pin
A
20
output
pin
PA
4
input
pin
PA
4
output
pin
*
2
IRQ
4
interrupt input pin
*
1
Notes: 1. IRQ
4
input when IRQPAS = 0. Note that in this state in modes 4
and 5, although the pin designation is output-only, IRQ
4
input is
also performed.
2. NMOS open-drain output when PA4ODR = 1.
PA
3
/A
19
PA
2
/A
18
The pin function is switched as shown below according to the combination of
the operating mode and bit PAnDDR.
PA
1
/A
17
PA
0
/A
16
Operating
mode
Modes
4 and 5
Mode 6 Mode 7
PAnDDR
*
1
— 0 1 0 1
Pin function Am output
pin
*
1
PA
n
input pin
*
1
Am output
pin
*
1
PA
n
input pin
*
1
PA
n
output
pin
*
1
*
2
Notes: 1. n = 0 to 3, m = 16 to 19
2. PAn output is NMOS open-drain output when PAnODR = 1.