general purpose IO & interrupts

Question

How can I hookup an interrupt handler to one of the five general purpose IO pins?
(I want an interrupt handler to execute if the signal on one of the IO pins changes).

Answer 1

It's not possible to do this on the Connect ME/Wi-ME. You'd need to use the Connect EM/Wi-EM to have access to a hardware interrupt. See the 'programming considerations' in the HW ref guides for the ME and EM as well as the HW ref guide for the NS7520 (you'll want to review the PORTAx and PORTCx pins).

Answer 2

Thanks for your reply.
I have read the HW ref guides for the ME and the EM but I didn't find anything about interrupts in those two documents.

The HW ref guide for the NS7520 does have information about interrupts and the GPIO pins, but how do I know the EM does support it and the ME doesn't?

So I would like to know where you found this information.

Answer 3

Check out the EM hw ref guide starting on page 41. Notice how it talks about the different registers and bits (i.e. PORTC3 for RXD2/GPIO-9).

Now look at the NS7520 hw ref guide at the PORTC register information starting on page 77 (87 of adobe), as well as the interrupts section starting on page 80 (90 in adobe).