Electronic – the difference between Interrupt on Change and External Interrupt on PICs

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What is the difference in function between IOC and EXT Interrupt on a PIC? I am currently using a PIC12F1822, and apart from the extra layer of checking you have to do with IOC (i.e. which pin caused the interrupt) the two are identical.

What is the practical difference if any? When would you use either one or the other?

Best Answer

Look at this document which states:-

Interrupt-on-change
This feature is similar to the external interrupt facility , except that a port change interrupt will be triggered by any change (not just one type of transition) on any of the pins for which it is enabled. This makes it more flexible (being available on more pins), but also more difficult to deal with correctly.