I've seen 3 instances of this with the EEPROM on a PIC16F913 app getting 
corrupted occassionally, and just a few weeks ago I found one instance that I 
could reproduce regularly.  Apparently powering the device on and off 
repeatedly causes the failure.  With Microchip's still-wonderful support, I 
found out quickly that brown-out detect was not enabled, and the corruption 
can affect EEPROM or Program memory equally, but EEPROM is usually more 
noticeable.  But BOD_ON fixed it!

Cheers,
-Neil.


On Friday 16 November 2007 12:06, Andre Abelian wrote:
> Hi to all,
>
> I use pic18f4550 and I noticed that the pic looses it's program memory
> I am not sure how many % but it is enough to see things are not working
> and this is my 3rd time I started doing hardware trouble shooting and I
> ended up reprogramming pic fixed the problem. The only possibility is the
> part got over heated while soldering. any idea?
>
> thanks
>
> Andre
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