After spinning my wheels way to long and doing countless “bing” searches, I wound up empty on why when I attempt to program my AVR chip I was getting an Unexpected Signature of 0x000102. This happened on an initial board I created, and didn’t know if it was a problem with the chip or something else. Once it happened on a second board with the exact same invalid signature, I knew there had to be a common problem.
If you found this via a search, well you know what I’m talking about…if not, you probably don’t care.
I finally tracked this down to a short between the reset line on my processor (underneath a SMD device) and ground. Cleaning up the board and life is good.
Hope this saves someone a little bit of time
-twb