>
>My answer is that the cap values are not as critical as you think. 15-30pF
>have worked fine with all the PIC based 20 Mhz crystal projects that I've
>done.
>
>This is a small detail that doesn't need to be sweated.

True, if you really don't care wether you are on-frequency, or if your
oscillator will 100% reliably start.
Otherwise, you need to check these things.

There's also a drive level spec, which should be checked.
You need to measure the voltage while running, and get the impedance on
resonance either from the DS or direct measurement (touchy).
Overdriving crystals leads to failures and can shatter the 32kHz fork types.

But, for the average hobbyist, the rule of thumb seems to be "ignore the
specs, just guess".

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