On Sat, Aug 24, 2002 at 12:46:57PM -0700, Brendan Moran wrote:
> >         Despite all the things I have tried in the last few months, I
> > STILL have not got a successful program loaded into my 16f628. I am using
> > TLVP with David Tait's FPP. I HAVE verified that the parport works by
> > using FPP's debug function, and every pin works out as it should. I have
> > rewired numerous times from scratch to ensure no errors. Initially, I had
> > a longer parport cord (6'), but I made my own that was much shorter. I
> > thought maybe this was the problem, but it works with the debug feature..
> > I verified each pin's voltage high and low with a DMM while switching
> > them with FPP's debug feature. Even the read pin works fine, as it shows
> > in the debug section. I have increased the cycle delays to mad numbers
> > that are extremely high, and still nothing works. It just sais Read: 3FFF
> > expected: 2828 (as 2828 was the first code to program). What is going on?
> > I am getting desparate here for nothing has worked. I have even switched PIC's.
>
> Try putting some capacitors (small ones, say 100 nF) on the inputs to the
> IC that you're using to interface to the PIC.

Decoupling caps? Probably a good idea. Or filter/antiringing caps from the
input lines to ground.

Any suggestions on a real simple termination scheme so that it'll work with
longer parallel cables?

Thanks for the suggestions Brenden.

BAJ

--
http://www.piclist.com hint: To leave the PICList
mailto:piclist-unsubscribe-request@mitvma.mit.edu