Using an external clock with an Atmega32

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#1
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When set to use an internal clock, my app works ok.

When set to use an external clock (fuses CKSEL = 0000 and SUT = 10) the chip does nothing. I assume I have something wired incorrectly.

I'm using this external clock:
http://www.abracon.com/Oscillato...

I have it wired like this:
pin 1 floating.
pin 4 to ground.
pin 5 to xtal1 on the atmega32.
pin 8 to voltage.

Does anyone have any sugesstions as to what I may have wrong?

Thanks!

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I would guess a busted oscillator. Do you have another to test with?

Those settings look ok, as long as you've got the pinout right. Do you have a scope you can stick on the output of the oscillator to test it?

Clancy _________________ Step 1: RTFM Step 2: RTFF (Forums) Step 3: RTFG (Google) Step 4: Post

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The oscillators are brand new. I've tested 2 of them with the same result.

I don't have a scope :(

Are my fuses set correctly? (fuses CKSEL = 0000 and SUT = 10)

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Yeah, those fuses look ok.

Try tying pin1 high in case the internal pullups aren't working?

Other than that, I dunno. It's hard to say without a scope to check the clock signal. Do you have another AVR you can test? Maybe the xtal input is fried...

Double check the connections is all I can think of.

Clancy _________________ Step 1: RTFM Step 2: RTFF (Forums) Step 3: RTFG (Google) Step 4: Post

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You didn't mention this but do you have a capacitor in your circuit? It looks like it calls for a 50pF max cap. If you enable CKOPT (which enables an internal 36pF cap on XTAL1), does anything happen? Also what frequency is the crystal?

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He's using an oscillator, not a crystal!

Leon

Leon Heller G1HSM

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it's 3.686 mhz