[sdiy] oscillator auto calibration

[jean-pierre.desrochers at ville.quebec.qc.ca]

>I'm confused about what the eeprom is storing. Does it store
>the intended frequencies, or the error correction needed?

Frequencies. 

>If it's the intended frequencies, then I agree with Colin.

Don't forget that if you use calculations for every readings
-you'll need to find the values that WILL be used for the
 frequency calculation afterward. 
 All this from the 12bits CV / PIC's ADC voltage.

-From the above value, calculate the actual freq to compare
 with the one read from the incoming square wave.

-Finaly compare both freq'S to make CV corretion from the PIC.

--> If you use Lookup table the incoming CV's 12 bits ADC value
    is the address that has the good reference freq to be compared ready to
be used.
    And it's fast!

J-Pierre