I don't work with AVR's too much and have been familiarizing myself with the Atmel Studio 7 and the Atmel ICE. And twice now i have manage to lock myself out of the the ATTINY441. And if I replace the Tiny with a new device it will work. I have searched the forum and see a number of similar issues but none of the solutions so far has worked.
Description of the problem:
All I was doing was just toggling an LED. And that was working. I made a change to move the delay to a function, compiled no errors, clicked Start Debugging and Break, I got "failed to launch debug session with debugWire". And when I allow Atmel Studio to enable the DWEN fuse, I get the error message "Failed to enter programming mode". I can't end the debug session as in some posts. I have cycled power and started a new project as a long shot no luck. The board is so simple, just a couple of LEDS, CDS cell, external 3 Amp supply at 5.0V. The reset line from the header is short, less that 0.75 inches in length and there are no caps or resistors on that line.
Look forward to someone educating me on how to get out of this. Until then I will keep thrashing until I find that nut.