Wed Jul 4 13:53:39 CEST 2007

AD conversion

2 things to determine:

- aquisition time (sample/hold settling)
- TAD (per bit sample time)

TAD should be as short as possible, but greater than the minumum TAD,
approximately 2uS for 18F1220. the datasheet says for the F version at
8MHz, to use 16TOSC, and for the LF version to use 32TOSC.

It was on 16TOSC, 20TAD.. put it to 32TOSC, but can't see a
difference. maybe the pots are too noisy. i tried to add a capacitor.
100n and 10u, but no difference..