external crystal oscillator problem

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Hi guys, I'm trying to use an external crystal oscillator on an ATmega8, dip package.

I don't know if the problem is my hardware or if I am programming the fuse bits wrong.

I have tried using the following fuse bits: CKSEL=1111 SUT=11. Is there anything else that I have to set ?

Hardware:

I am using an Abracon Crystal (PN: ABL-8.000MHZ-B2) http://www.abracon.com/Resonators/abl-2-3.pdf

I am using 2 22pf caps (PN: 140-50N5-220J-RC) http://www.mouser.com/catalog/specsheets/XC-600144.pdf

I have it hooked up in the following way

     22pf
 +----| |----+-----o XTAL1
 |           |
 |          ---
 |           =
 |          ---
 |   22pf    |
 +----| |----+-----o XTAL2
 |
--- ground
 -

I'm not a cartoon character but I play one in real life.

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I use the same fuse-setting CKSEL=1111 SUT=11 for a 8 (or 16) MHz crystal. Should work. Maybe you locked yourself out ?? by programming lock-bits or disabling ISP ??

Btw, let's get the names right: you're using an external crystal, not a crystal oscillator: a crystal oscillator will deliver a clock-signal on its own, where an external crystal needs to driven. Crystal oscillator have (in general) 4 legs, crystals 2 .... sometimes three, where the third is connected to the housing

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Plons wrote:
I use the same fuse-setting CKSEL=1111 SUT=11 for a 8 (or 16) MHz crystal. Should work. Maybe you locked yourself out ?? by programming lock-bits or disabling ISP ??

When my ISP stopped working I took out the Mega out and put it into the STK500, by setting its software oscillator to 1Mh i was able to write to it and reset it to the internal clock.

Plons wrote:

Btw, let's get the names right: you're using an external crystal, not a crystal oscillator: a crystal oscillator will deliver a clock-signal on its own, where an external crystal needs to driven. Crystal oscillator have (in general) 4 legs, crystals 2 .... sometimes three, where the third is connected to the housing

TYVM, for the lesson. :)

I'm not a cartoon character but I play one in real life.