So the "Avoiding A/D noise toggling output pwm" thread has me thinking
about a recent "hack" project.

It was a complete junkbox adventure and I used two pots that I didn't
realize at the time were LOG taper. It's by no means critical, but the
feeling is the old 80/20 rule - 80% of the useful range is in 20% of the
pot travel. So I'm thinking through how to linearize their values.
Yes, the simple answer is:
A/D -> math -> value
But I'm thinking creatively this week :-)

I know you can add fixed resistors across a linear pot and get a LOG
approximation, but I've not explored the reverse..?

If I'm forced to do it mathematically, does anybody have an efficient
algorithm?

I'm thinking the cleanest way may just be a lookup table crafted in Excel.
A full 10 bit (1024 value) lookup table is probably overkill, but it has
the virtue of simplicity.

-Denny
--=20
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