Crystal Oscillator Accuracy

Frustrating about the 1v4 - I'll test it when I get back from holiday in a week. Not sure if there's much I can do if the crystal isn't the right frequency, but if it is stable then at least the calibration might work.

So far 7800 ppm is terribly better than 100 000 ppm, and it should ease a lot of log.

true :)

Interesting idea exposing it in such a way that it can be calibrated by an external input. I'll have a think about that.

As far as I understand there are some eeprom available to save calibration results.

Sadly no (maybe on the L1?) - but it could go into flash along with the saved code.