I changed the clock fuse bits on my ATtiny85. Now I can't flash anything to it or even change the fuse back. I get the error:
avrdude.exe: Device signature = 0x000000 avrdude.exe: Yikes! Invalid device signature. Double check connections and try again, or use -F to override this check.
The command line command I used to change the fuse initially was:
avrdude -p attiny85 -P com8 -c stk500v1 -b 19200 -U lfuse:w:0x62:m -U flash:w:main.hex
Now I understand that I set the clock fuse for an oscillating clock signal, not for a crystal. I read here that I can supply the necessary clock signal from an stk500. My Arduino UNO is functioning as programmer (and in the command line args, I actually tell avrdude that it's an stk500). How do I connect/configure UNO and ATtiny to supply the necessary clock signal?
I'm not trying to use High Voltage Parallel Programming. I just want to supply the external clock signal which the AVR now expects in order to program it as normal.
I have a second Arduino, and I tried to send a 16MHz square wave to pin 2 (CLK1) of the ATtiny85, using the code on this page. However, when I tried to program the AVR with both Arduinos hooked up to it (both the clock and the programmer), I got the same error as before. Any idea what's wrong?