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External Interrupt not working - 16F877

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Hey all,

This is my first post. I'm trying to program a 16F877 using CH Flash Basic, the CH stands for Celestial Horizon. Problem I ran into yesterday is this: tried to get the external interrupt working. Got the program similar to an example I saw, but it didn't work. Have any of you noticed problems with RB0 since it's next to the power pin. I moved my requested input down to RB7 and wrote just a simple polling op for that pin and it worked just fine. Either my interrupt programming is just plain wrong or I'm getting interference at the pin.

I've got an LCD hooked up and the program is just basically supposed to switch between two text lines until a button is pushed, then it's supposed to go to a subroutine and execute it.

Like I said it worked if I just use polling for a pin input, but not when I tried to use the external interrupt. I'd prefer to use the interrupt version since I want it to have an auto shut off if there is no activity after a minute or so.

Any help would be greatly appreciated.
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