I was planning to use the internal CVREF on the 18F26K20, but I'm
confused by microchip's documentation. On page 291:

CVRR: Comparator VREF Range Selection bit
1 =3D 0 to 0.667 CVRSRC, with CVRSRC/24 step size (low range)
0 =3D 0.25 CVRSRC to 0.75 CVRSRC, with CVRSRC/32 step size (high range)

When CVRR =3D 1:
CVREF =3D ((CVR<3:0>)/24) * (CVRSRC) + VREF-
When CVRR =3D 0:
CVREF =3D (CVRSRC/4) + ((CVR<3:0>)/32) * (CVRSRC) + VREF-

With 4 bits, 15 being the maximum CVR value, how can you get .667
CVRSRC? I get the value of .625 CVRSRC max.
When CVRR =3D 0, I again get 0.71875 CVRSRC and not .75 as advertised.

It looks like they plugged 16 into the formula to get .667 or .75
CVRSRC values.

The datasheet in question is available here:
http://ww1.microchip.com/downloads/en/DeviceDoc/41303G.pdf

I haven't tried it in circuit yet, or looked at any other datasheets.
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