I am servicing pcb’s with a SMD atmega8 on board. where these have failed, I have them removed & replaced by a professional. I use the USBasp hardware from Core Electronics, with AVRdude & “Bitburner” software After a gruelling setting up, it all seems to be working correctly, I have now reprogrammed approx. 15 boards. 10 successfully, but 5 boards have failed to operate. of the failures I have replaced the atmega8 again & have successfully programmed 2 of them. After loading the prog, it verifies the prog & fuse bits as correct. The “lock bits” I leave alone, [my gear does not appear to be able to read or write the lock bits] So I would very much like to know what is not right. I am a total newby with Atmel, have some experience with PIC’s. Any help would be appreciated.
It seems to me that if you have replaced the atmega8 and reprogrammed it and it has failed twice more, then the problem likely lies with another fault on the pcb and perhaps not the atmega8 itself.
I would suggest programming the atmega8’s beforehand and testing them to rule out the possibility of an error on the PCB itself. One of these would be really handy:
You can add something to your sketch potentially that will blink the LED on this breakout when the board has been programmed, but doesn’t have any functionality in your PCB.