On Wed, Apr 08, 1998 at 01:30:42PM +0100, John Midgley wrote:

> I have a *very* simple program (in fact I've had several different goes) that
> attempts to make use of a pulse (1-2ms, yeah, yeah; you know the one.),
> by launching an interrupt routine on a rising edge on RB:0.

You haven't said what device you are using; check to make sure the pin you're
using is not shared with some other function. Attached is a C program that
does work in hardware, using interrupts on RB0/INT. Here's
a suggestion; in your main loop, continually copy the current state of RB0
to an output pin, so that you can monitor on a CRO the level of RB0
as seen by the PIC. This will confirm that the input pulse is good.

Also, double check that spec of .45Vs - is that true for INT? It's certainly
not on some PIC chips. The spec for I/O pins and INT may be different.
Also verify the logic low leve.

Clyde

--
Clyde Smith-Stubbs               |            HI-TECH Software
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HI-TECH C: compiling the real world.

Attachment converted: wonderland:intr1.c (TEXT/MSIE) (00003185)