Aubrey McIntosh, Ph.D. wrote:
> The system programs erratically.  I have tried various I/O delays
> under settings -> hardware and it does not become reliable.

I don't understand what I/O delays on the Windows side should have to do
with anything.  What is the connection between the PC and this programmer?
Is it using a COM port?  Whatever is receiving the commands from the COM
port must deal with the real time issues.  These are too fast for a PC and
serial communication.

> The starting address for the
> transition is random, but in the very low memory range of 0x0010 to
> 0x0030.

This is exactly the symptom you can get when MCLR isn't being pulled to 13V
fast enough.  Note the fast rise time requirements specified in the
programming spec.  It sounds like MCLR is spending far too long around 5V
before going to 13V, probably due to the PC trying to handle real time
issues.  Again, whatever is receiving the commands from the PC should be
dealing with real time issues.  Everything should work with arbitrary time
between bytes from the PC.


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