hi
i know that programing fuse bits wrong is questioned a lot , but this is new
i have done some thing silly that i don't think if any idiots might do that
i have atmega1280 and for the cksel3-0 i programmed 0001 ( of course instead of 1110 )
and this fuse bit is reserved ( as data sheet says ) i don't know for which use
so0 any idea i can recover my chip ?!!!!!!!
it doesn't work and when i applied an external clock to XTAL1 pin on atmega1280 , the XTAL2 pin has some kind of wave form similar to the input clock but is not as strong as input clock , does it shows any thing especial ?
i mean what should it be like in any situation , internal or external clocks , in crystal mode ,
any hint to detect in which mode my avr chip is working ?

 

Is the particular chip expensive or important? or the software on it?
Being Atmel, it's about the most likely to reset with fast power cycling
on the supply, ground and clock lines independently.
Most of the time it wouldn't be worth the hassle to save the hardware chip.
If you recover it to a useable state, some or all of it's program memory will also be corrupted.

 

your chip is maybe my expensive so0 i just tried to save it that i couldn't
but i think its help flu to know the status of the pins XTAL1 and XTAL2 in any situation