how to use external crystal?

[AvionicsMaster1]

On page 100 of the manual it shows listing the config fuses in a different format than you've been using. Could be worth trying.

In the above you've got #define OSC 20 and you need to get rid of the pound sign. I'm assuming that would be the same for the code-size statement also.

You could also do most of the above with the CONFIG1=xxxxxxxx and CONFIG2=xxxxxxxx. Something else to try maybe.

Just a few thoughts that may be horribly bad.

[Pista1]

What happens if you turn _IESO_ON to _IESO_OFF ? In CONFIG of course. Is there a way to detect if the crystal oscillates?

[AvionicsMaster1]

I found this and thought it might help http://ww1.microchip.com/downloads/e...efinitions.pdf. It might be of interest.