At 08:16 AM 4/30/01 +1200, Russell McMahon wrote:
>  What sort of caps are you using?
>Presumably Mylar or similar rather than eg ceramic.
>
>Does transferring this from the ICE to a "real" PIC produce an identical
>result?

Difficult. I've only got one board, and it's SMD.

>Presumably when you say "non-linearity" you mean non linear compared to an
>exponential curve.
>
>Might it help to eg go low, then high, and time for say 5 time constants
>after the low to high transition and then go low again and count the time
>taken?

That's what I'm doing.  Charge for long time (verified on scope to flat)
then discharge and time.


>That way, even though the 5 time constants "should" pretty much have
>the cap at top rail, driving it there for a consistent period after it
>passes through low-high threshold may reduce variability.

I'm charging it way into the flat.
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