Hi Alain, thanks for the info, can you just confirm that you tried the 648A with the CLEAR.
The PCB is a commercially made board, currently in use, and just has the pic changed. I have tested 2 PCBs known working, with same result.
If yours does work, then I think there can only be 2 suspects left.
Suspect 1
The pics, I have tried 3 brand new ones, and all show the same problem, I have more but they are all the same batch, I will have to see if I can get a different batch.
Suspect 2
The programmer is not programming correctly, I use the Melabs EPIC programmer connected to LPT2, correct PSU and correct programming volts (re-checked this morning).
The EPIC programmer software is 2.46beta, latest for this from Melabs site. I have tried the Melabs programmer 4.32beta, but that does not work, it does not read the chip ID.
I will have to take the hex file to a friend tomorrow and get him to program the pic, at least that would rule out the programmer one way or another.
OH...... yes there is a final suspect.......................Me !!
Thanks all for your help.
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