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[SOLVED] Resetting fuse bit in ATmega8

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5282604

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hii .
i write a wrong fuse bit for my atmega8 .
and i can't programming it via my usb asp programmer .
and in data sheet i find an parralel high voltage prorammer.

and i find this video


this high voltage can reset my fuse bit ? .
 

alexan_e

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Re: avr fuse bit problem

I suppose it is your idea of a joke...
 

5282604

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Re: avr fuse bit problem

thank you
i build a fuse bit doctor circuit
but it not reset my fuse bit chip ?

top.jpg
 

alexan_e

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Re: avr fuse bit problem

So are you seriously asking, I thought you were making a joke with the burning chip video.

Do you know what is the fuse setting that you have applied?
The fuse bit doctor should fix any clocking or reset/isp setting problem.

You can also try https://www.edaboard.com/threads/105462/#post907231 , it uses a mega8 to unlock another m8 using parallel connection
 

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Re: avr fuse bit problem

thank you :grin:
my fuse bit like this

fuse bit.png

fuse bit 2.png

and it can't reset my avr by fuse bit doctor
 

alexan_e

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Re: avr fuse bit problem

Your settings have programmed the mcu to a ceramic resonator and have disabled the reset pin (works as I/O).
Without reset you can only use the parallel programming to program the mcu

I haven't use the fuse bit doctor but if it didn't work you can try the circuit I have suggested or make a parallel programmer
 
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