AVR-Chat

>  The option is there to NOT have that fuse programmed and your part will
> work fine, usually, and on occasion go into the weeds for no apparent
> reason.  I've spaced that fuse and scratched my head before.

Exactly.. Using the "low power mode" is the default, and I don't know
why Atmel did it that way, but that's what we're stuck with.
In the files area, is a little program I wrote called "Fuser", which
uses a tiny to fix the fuses on systems that accidentally got deployed
with the default on the CKOPT fuse.

>  Some parts have the option of spitting the clock out an IO pin (MEGA168
> for instance) and you can use that to clock other parts in the circuit,
> or to check the clock frequency if that is your desire.

That's cool, since there's a buffer between the probe and the actual oscillator.

I want to be really clear, that measuring the frequency of oscillation
is nowhere near good enough to ensure proper operation of the
oscillator.