fuse booboo

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Well I just programed my atmega8's low fuses for a crappy clock source, I meant to program he high fuses... this is what I *think* I set my mega8's clock source too:

CKSEL0..3 = 1001
SUT0.1 = 10

a quick lookup under clock sources shows its expecting:

External Low-frequency Crystal
and
Stable frequency at start-up

I do not have a low freq crystal at my disposal, I have a butterfly on the way though, if I have to, I will 'hijack' its signal to repair my mega8, I cant stand knowing one of my babys is hurt, I have more 8's but I would never just toss it out without trying all I can.

I do have alot of crystals lowest size being 3.6864 mhz (a 1.8432Mhz on the way) highest being 20mhz, how low is it expecting? if I was to put the 3mhz crystal on another AVR and put CKDIV8 on and CKOUT, do you think that could fix it?

I tried using an attiny45 at 8mhz with ckout, didn't work, didn't respond... I also have some 555timers and a 1.8432Mhz oscillator (that I think I broke, should I have used 5vs with it? i cant find its datasheet)

Any ideas? or is it screwed?

-Thanks guys, Brent.

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You need an actual (parallel resonance) crystal on the XTAL1/XTAL2 pins, and not a logic clock. "Low Frequency" is under 1MHz IIRC, but try what you have - it might just work.

ButtLoad can provide a clock out for fixing AVRs whose fuses have been misconfigured to accept an external logic clock. You can also try using the 32.768 watch crystal on the Butterfly board as a crystal for the MEGA8, but then you'd need an ISP speed of less than about 8KHz.

- Dean :twisted:

Make Atmel Studio better with my free extensions. Open source and feedback welcome!