These seems to have been discussed on here before, but I can't seem to figure out my problem.

I've got a 12F675 setup and it will program a couple of times and now it doesn't program and won't erase. I'm using MELabs Serial Programmer and trying to set it up so that MCLR is an input and the internal osc is used. From my research this seems to be the combination that starts causing issues for other people. I'm guessing I erased the OSCAL Value and BadGap presets, but I'm not sure how to get them back.

Since MCLR is set as an input I have a 5k pull-down resistor on it which is needed for my circuit. I'm not sure if that will cause an issue or not. My board is SMT so it is a little hard for me to modify, but I can try hooking MCLR to 5V through a diode to see if that helps.

The config fuses seemed to work properly with the following:

OSC = OSCINT
POR = ON
BOR = ON
MCLR = Input Pin
CP = ON
CPD = ON

I can read the dead circuit with the MELabs programmer, and all the fuses come back as above except OSC is set for LP.

From my reading it sounds like I need to forget about using the MCLR pin as an input, but if I can help it I would rather not change my schematic and board design.

I appreciate any input

PS. Does anyone know how the MELabs programmer handles the OSCAL and BandGap presets on the 12F675?