I have a project I set aside a few months ago in a "mostly done" state.  I 
finally got back back to it today planning to fiish it up.

When I powered it, it seemed completely dead.  After 30 mins of 
troubleshooting, I decided to see if I could read the PIC (16F628) in my 
PicStart plus (using MPLAB IDE 7.21).  It showed up in a weird state, the 
config bits wrong, including code protect set to all (I don't use code 
protect during development).

I tried blanking the device which doesn't generate any message then when I 
try to program it, MPLAB says:
"Program Memory or EEPROM Data is protected. Reprogram
the entire part.  If "Auto select memory areas and range"
on the Memory Ranges tab of the programmer settings
is enabled, it must be disabeled  before proceeding."

Even with the auto select feature disabled.

I decided the chip might have been damaged, so I got out a new 16F628, 
programmed it and put it in the project.  It worked fine for about 20 
seconds, then the PIC got so hot it would burn me if I touched it for more 
than a fraction of a second and the project stopped working.  When I put the 
PIC back in the picstart it behaves exactly as the original chip that wasn't 
working.

When I put a damaged pic back in, the project is totally dead, but the pic 
stays cold.

Any ideas what could be going wrong here?  It was working fine when I 
shelved it a few months ago.  I spent a lot of time looking for loose 
connections that might be shorting, and the only possibility is that I 
grounded pin 16.  This is RA7/OSC1/CLKIN.  My oscillator is set for 
INTRC/IO.

I've fixed the loose connection that might have caused the short, but I 
really don't want to blow another chip, especially since I only have one 
F628 left.

Jason 


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