ATMega8 CKSEL fuse setting for above 8 MHz.

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I have looked at the Spec sheet for the ATMega8 for setting the CKSEL Fuse bits. I can see where it can be set for up to 8 MHz.. External Crystal. How do I set the CKSEL bits for an external Crystal from 10 to 16 MHz. I must be missing something on the spec sheet. It looks like the maximum External Crystal setting is only 8 MHz. whereas the ATMega8 can operate up to 16 MHz.?

Thank You,

Vince

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On my 16Mhz crystal-driven ATMega16, I set mine to CKSEL=1111, SUT = 11 which is described on the AVRStudio/STK500 Fuses tab as "Ext. Crystal/Resonator High Freq.; Start-up time: 16K CK + 64ms"

AFAIK, this is the same for ATmega8....

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When operating above 8 MHz, it is also recommended to program the CKOPT fuse, to provide a full rail-to-rail voltage swing on the crystal oscillator. You'll find it consumes more power, but it is intended to improve crystal stability.