Phillip Coiner wrote:
> I bought a pro_prog from Olin and I can't get the thing to work.

Like I said in my last private message to you, any time you want to give up
just send it back for a refund.

> He is telling me to check for cross talk but I am not convinced that
> is the problem.

I'm trying to help you diagnose this, but you keep trying to tell me what
the problem isn't and not run the tests I ask for.  I don't know if it's
crosstalk, but I have seen crosstalk be a issue in several cases.  Just
because the ICD2 works with a circuit only means the lines are connected
correctly, not that all other programmers should work.  Each programmer has
different characteristics.  Your cable uses a unusual pinout that puts Vpp
adjacent to one of the programming signal lines.  I don't know if that
matters, but when Vpp rises 13V in a microsecond or two, it doesn't take a
lot of capacitance to make a glitch show up elsewhere.  You also have PGC
and PGD adjacent to each other.  Again, I don't know if that's the problem,
but I have seen it be the problem in other cases.

> I laid out the board and I know the lines have only about 1pf (if
> that) with the trace widths and PCB stack up I'm using.
>
> I can take the cable whilst plugged into the board and use it with an
> ICD2 and it works fine.

You are making assumptions about why I'm asking for these tests and what the
causes of a failure are limited to.  There is more that can go wrong than
you are apparently aware of.

> I think there is something strange going on but I can't figure it out.

I agree with this one.  So far I don't have a explanation of why it won't
work with your target system either.

> I was wondering if there is anyone out there that is using a pro_prog
> with the 18F family parts?

Many, although I don't know how many on this list.

> If so can you tell me the rise & fall times for the edges of PGD and
> PGC?

As I said in my last private message to you, I expect a few 100nS, certainly
not more than 1uS.


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