Has anyone experienced problems in programming PIC's whilst in situ
(In-Circuit Programming)

I have a P16PRO purchased from Dontronics (about 1.5yrs ago!) and it's been
fine for leaded (through hole DIL) parts but I thought I could be clever and
just wire the specific programming pins (RB6,7, MCLR and 0V,5V) from the
P16PRO and program my surface mounted PIC on the fully built circuit.
Specifically they are 16F8X and 16F87X series.

I can only seem to be able to do this if I attach a couple of scope probes
to the programming pins and then it's very very touch-and-go.

I'm assuming the scope probes provide some kind of capacitance and is
therefore smoothing out noise on the data or clock lines? Does this sound
right?


Is the following statement found on the site the key to my success?
http://www.picallw.com/#HARDWARE

"If you have problems by programming (Programming Failure) and you have a
new 486 or pentium motherboard with LTP port on motherboard, then you must
connect an additional ceramic capacitor (330 to 470 pF) between ground and
pin RB7 on TEXTOOL or you can add additional pull-up resistor (4k7) to ACK
line and +5V"

I have both a Pentium I 200MHz Laptop and a AMD Athlon 800MHz Desktop and
both give the same problems.
I've tried the 4k7 extra pull up but this makes this worse I think.

Any suggestions?

Regards

Pete

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