INT0 Zero Interrupts

[nemesis]

Hi All,
I have been banging my head on the wall for weeks. I am not sure what I am missing and I have read over the datasheet many times. Please take a sec to see if you notice anything wrong.

I can't get INT0 to interrupt. The TMR0 interrupt is working great, the led flashes 100ms as desired. If I take pin RA0 and jump to 5V or Ground the interrupt doesnt seem to interrupt. The program should turn on an led if it interrupts.

MCU: PIC18F1330

Thanks Again,
Nemesis

[Archangel]

I gotta ask . . . Why do you put the percent sign before the value of your variables? It seems to me you are telling the Variables, ports and registers to read binary, and I suppose as long as you only use zero and one it will work, but it's confusing as all get out. Why not just use 0 and 1 ?

[nemesis]

Percent madness... I try to make my variable names start with bt for bit, w for word, l for long. The percents really just remind me they are bits. I totally could ditch them. lol maybe I should.

Thanks for looking at the file. I can't figure out what I am missing, really hoping someone finds something.

[Archangel]

The chart sec 9.1 shows INT0 port latch as 1 not zero when INT0 enabled. Other than that I see nothing, but I am really sleepy right now Doggone PBP interrupts, it doesn't take much for them not to work . . . You might try commenting out the parts that do work until you hit the right formula . . .

[nemesis]

Anybody pick up anything else? I feel really frustrated with this interrupt. I think I will try pulling out everything but that interrupt as Joe suggested. Just hoping that maybe the order or bit is wrong in one of the registers.

[nemesis]

Thanks for your replies Joe S.

I figured out the problem. My ADCON1 should have been:

ADCON1 = %00011111 ' Set all to digital

Thanks Again,
Nemesis

[Gusse]

After INT0 interrupt you are not clearing INT0IF variable. I don't know does it make difference or not, but add

INT0IF = 0

before last ENDIF in INT0 interrupt section.


Also TMR0 comment is not valid. It should be ON

INTCON =  %10110000 ' Global, TMR0 off, INT0 ON

BR,
-Gusse-

[nemesis]

Will do thanks Gussee. Sometimes I am victim of my own cut and paste. Thanks again all.

-Nemesis