fuses

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hi everyone.. i was curious.. is there anyway u can comunicate with an avr once and external osc fuse has been set(but u dont have that osc attached)? or reverse this process.. its easy to accidently do this with the stk500

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I'm not sure if it will work but you can try to connect an RC to XTAL1.
Connect a resistor of 4700 Ohm between Vcc and XTAL1 and connect a
47pF capacitor between XTAL1 and GND.
You should keep the connection lines as short as possible.

If the RC oscillator won't swing (since you have selected external clock) you have
to build your own oscillator.

Regards
Sebastian

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oh ok i thought i would have to. ne way thanks for the reply Sebastian. 8)

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Quote:

i thought i would have to

Well, not with the setup that you described. If you have an STK500, then there is a perfectly good software clock on one of the pins of the OSCSEL header. If your AVR is mounted in the STK500, then it is real easy--instal the jumper to the correct postion. If the AVR is not mounted in the STK500 a clip lead can take the STK500 clock to the XTAL1 pin of your target AVR. For the few seconds to reset the fuses you can just hold the lead there. [Can you tell that I have been there, done that, and gotten the T-shirt?]

Lee

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