I have a G120 on a custom board I have built. It has been working great for a little while. The other day it suddenly stopped running so I attached a serial cable and opened TeraTerm. I erased the memory and tried to XMODEM ‘G120_TinyBooter.GHI’ to the board. It takes it but still says ‘Bad firmware’. I have seen memory error contact GHI before but never this symptom.
I have verified that the board is getting 3.3V and proper grounding. I do not have pin 59 attached to anything.