wouter van ooijen wrote:
>> Shooting from the hip here... it sounds like your reset line comes up 
>> too slow at programming time. 
> 
> I had exactly that issue 10 years ago when I started programming 16c84's
> using an almost-zero-components serial port progger. ICSP worked, but
> only when the xtal was removed. The cause was as Marcel guesses: MCLR
> rise was too slow.
> 
> Do you have a cap directly tied to MCLR?
> 
> Wouter van Ooijen

Actually, there's no reset circuit.  /MCLR is set to I/O mode and the 
only thing connected to it is Vpp on the ICSP header.  (However, if 
capacitance is still a problem, it bears mentioning that this is a 
solderless breadboard.)

Someone else mentioned that it might be a "use VPP first program entry" 
thing.  I can't test that theory yet because pk2 (the PICkit 2 driver 
program on Linux) doesn't yet have a Vpp before Vdd setting.  I'm 
working on getting a copy of Win2k on a spare machine to see if this is 
indeed the problem...

Thanks
dro
-- 
http://www.piclist.com PIC/SX FAQ & list archive
View/change your membership options at
http://mailman.mit.edu/mailman/listinfo/piclist