Bruce Bowling <PICLIST@MITVMA.MIT.EDU> wrote:

> I am using a 16C56 part to measure pulse widths (in the 0 to 10 ms
> range). My problem is that I am getting unreliable input pin
> detection within software. I am driving the pin with a test 50
> percent duty square wave, and the measued pulse is correct most of
> the time, but on random occasions the software indicates that the
> pulse is slightly longer than it really is.
> ....
> I believe the software is working correctly, and the problem is
> With the hardware implementation.

Bruce:

Please (1) show the relevant portion of your code, (2) tell us your
PIC's clock frequency and the frequency of your 50% duty-cycle
square wave, (3) describe precisely what "slightly longer" means,
and (4) tell us that you've looked at the incoming signal with an
oscilloscpe ON THE PIC's I/O PIN and have seen nothing but clean,
fast-risetime square-waves there.

-Andy

=== Andrew Warren - fastfwd@ix.netcom.com                 ===
=== Fast Forward Engineering - Vista, California          ===
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