Setting AVR fuses can be a real pain in the ass – especially for newbies. Well, not anymore – theoretically, there is nothing with fuses that cannot be undone. One condition – you need proper tools. To repair fuses, you actually need an HV programmer, which is actually easy to build. Especially this one so-called “Fuse Doctor.”
The actual board is designed to support ATTiny2313, ATmega8, ATmega16/32 microcontrollers in DIP-packages. It has a long list of supported AVR chips. Most of them have to be connected somehow externally via your own adapters or another way. What is good about it? – It’s cheap, it’s simple, and it doesn’t need a computer to operate. All tasks are done by preprogrammed ATmega8, which detects the chip by reading its signature and repairs fuses to factory settings with only one button click. Just put your messed MCU into the socket and click Start to detect and reset fuses to normal condition. Additionally, a connecter would like to connect an RS232 adapter and see how the healing process is working in the terminal window. So if you would like to have a backup plan for your AVRs, you should definitely build this one – otherwise, you can always buy a new chip.