From: "Andrew Warren" <aiw@CYPRESS.COM>
Sent: Wednesday, August 18, 2004 5:05 PM


>     It's easier to divide by 4 to get 0-255... And if you then map 0-30
>     to 1, 31-230 to 1-200, and 231-255 to 200, you'll be sure to have the
>     entire range even if your pot doesn't quite go to the ends of its
>     travel.

When I said divide by 5, I didn't mean throwing away information; for
example 633 would become 126.6Hz which is a different result than 634 which
is 126.8.  I could use your way and then have my values rounded to the
nearest 0.25 instead of 0.2, but I don't know that it will be that important
to compensate for a pot that doesn't let me get to the end of the range.
Especially if I'm using a 10-turn pot which should be of generally higher
quality and much more likely to get to the end of its range of travel.

>     Don't use floating-point math for this... Use a lookup table.

That would be easiest, but are their shortcuts if I go that route?  I'll
have 1000 input values, and I'll need 2 bytes to output for each one (number
for 100uS and number of 10mS to delay).  That means a 2000 value lookup
table.

Jason

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