Hi John, I use the PSP for ICSP on many projects,
and have never had a problem with it. I typically
have the wires from 30 to 60 cm length, with never
a bad program or verify. Are you using ribbon cable?
That will have much higher capacitance than just
running 3 wires between the sockets. The reason I
say 3 wires is that I run the ground wire from
the PSP socket to the board ground of the target
board totally separate from the 3 other wires.

The 3 wires are cabled tied loosely together and
run maybe 15cm away from the ground wire. I have
good cap meters here and can measure the
capacitances if you like. :o)
-Roman


John Walshe wrote:
>
> Hi Alan,
>     As you know the Picstart is "not supposed to be used for ICSP" - however
> I also use it all the time for ICSP. But however, you do have to watch the
> wire lengths(a few cm at max) and the load that the "other circuitry is
> presenting to the PS+ (it has zip of a drive capability). Make sure nothing
> else is connected to the VDD line and try it again(I assume RB6&7 are
> buffered adequately from the circuit). I've recently had a problem
> programming a 628 where the code was getting in the first time but second
> time it was screwed up and config bits were not being set etc (similar to
> your case) - the offending item was a 100nF cap across the VDD/VSS near the
> pic. Removed that, and everything worked perfectly.

--
http://www.piclist.com hint: The PICList is archived three different
ways.  See http://www.piclist.com/#archives for details.