I/O Port Control Register For External Interrupt - Samsung S3C2501X User Manual

I/O PORTS
12.3.4 I/O PORT CONTROL REGISTER FOR EXTERNAL INTERRUPT (IOPEXTINT)
If the port is used for a function's port such as an external interrupt request, its signal function is determined by
the IOPEXTINT register. IOPEXTINT register is used to configure external interrupt request signals. I/O ports
provide 3-tap filtering, and you can select filtering on or off. External interrupt provides level or rising or falling
edge detection. If you set rising or falling edge detection, rising or falling edge interrupt makes interrupt status
high. You can clear the interrupt by writing IOPEXTINTPND register to '1'. If you set level detection, then external
interrupt level goes direct to interrupt controller. External signals can be active high or low, so you must set the
active high or low bits for the proper operation.
Register Address
IOPEXTINT 0xF0030014
12-8
Table 12-5. IOPEXTINT Register
R/W
R/W I/O port special function register for external
interrupt
Description
S3C2501X
Reset Value
0x00000000