
HYUNDAI MicroElectronics
26
2.7. EXTERNAL INTERRUPT
An interrupt request is generated when a level-change from "H" to "L" or "L" to "H" of
INT0,INT1,INT2,INT3 pin is detected. The edge of external interrupt is selected by interrupt edge
selection register(IEDS) and ports(R40,R41,R42,R43) corresponding to INT0,INT1,INT4,INT3 are
determined as a input port for external interrupt by bit0~3 of port4 mode register(PMR4).
EXT. INTERRUPT EDGE SELECTION REGISTER
<00D0
H
>
PMR4
7
T3S
6
T1S
5
EC2S
4
EC0S
3
INT3S
2
INT2S
1
INT1S
0
INT0S
W
W
W
W
W
W
W
W
R40 / INT0 Selection
0 : R40 ( Input / Output )
1 : INT0 ( Input )
R43 / INT3 Selection
0 : R43 ( Input / Output )
1 : INT3 ( Input )
R41 / INT1 Selection
0 : R41 ( Input / Output )
1 : INT1 ( Input )
R42 / INT1 Selection
0 : R42 ( Input / Output )
1 : INT2 ( Input )
<00F8
H
>
IEDS
7
IED3H
6
IED3L
5
IED2H
4
IED2L
3
IED1H
2
IED1L
1
IED0H
0
IED0L
W
W
W
W
W
W
W
W
INT0 Edge Selection
00 : -
01 : Falling
10 : Rising
11 : Falling & Rising
INT1 Edge Selection
00 : -
01 : Falling
10 : Rising
11 : Falling & Rising
INT3 Edge Selection
00 : -
01 : Falling
10 : Rising
11 : Falling & Rising
INT2 Edge Selection
00 : -
01 : Falling
10 : Rising
11 : Falling & Rising