At the expense of making two chips unusable, I have now found the error.

It looks like the configuration word-settings are wrong. The
template-code for a 12F629 from Microchip had this line:

__CONFIG   _CP_OFF & _CPD_OFF & _BODEN_OFF & _MCLRE_ON & _WDT_OFF &
_PWRTE_ON & _INTRC_OSC_NOCLKOUT

Since it's a template, I did not add too much attention to it except
for making sure MCLR was on. The first chip was programmed and tested
and then I had to change the code. When trying to reprogram, MPLAB
reported what I wrote earlier. After a lot of trial and error-tests
(I'm still a newcomer to the PIC-world) my mind ended up thinking "the
chip could be damaged", so I took a new one.

The second one got programmed, no errors this time. So the first chip
must be faulty, perhaps ESD or something. I put it in the protoboard
and tested, and found that I had to change the code yet once more.
Trying to reprogram it, MPLAB yelled once more about the errors.
Spending several hours, I still couldn't get it to work.

I then used my last chip and put it into the socket. But before
programming, I peeked the configuration word once again and searched
for info about what CP and CPD is. This looked like some Code
Protection. Since I did not know what it was, I read about it in my
reference manual and there it says that if code protection is ON, I am
not able to reprogram chips.

But, the config said OFF in the template, so this couldn't be it. Or, could it?

Changing OFF to ON (albeit sounding illogical) did solve the problem.
The chips were now NOT code protected, I could reprogram my third and
last chip several times without getting the previous errors.

So after several hours it looks like the values in the *.inc-file has
got the wrong values. The good news is I found the error before I ran
out of chips. The downside was that I wasted two of my three chips.

I will notify Microchip about this error.


-- 
- Rikard - http://bos.hack.org/cv/
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