I doubt if the sea level pressure (P1?) varies that much - 800 to 1200,
perhaps. Even 800 suggests a hurricane!!!

What I did with my system was to use the equation (in my case y=x^0.386 or
whatever) to generate a set of values of y vs x over the expected range of
x (in my case, x was from 1 to 100). Then I used a program I have to fit a
polynomial to the data. I ended up having to break the data up into two
ranges, and fit a 3rd degree polynomial to each range (1<=x<=12, and x>12).
I got a fit to about 0.1% accuracy. I then used the floating point package
in my program to evaluate the polynomial as I read X from the A/D converter.

I'll use your equation and try to generate a polynomial or two for you.

Read the AN660 app note - you might be able to use it if you have a PIC
with enough program memory.

Larry

At 03:01 PM 1/9/2003 +0000, you wrote:
>Scott:
>
>p1 and p ranges: 100.000 hPa to 1200.000 hPa
>
>ok ??
>
>Tanks!!
>
>[]4s
>Jeferson Martin

Larry Bradley
Orleans (Ottawa), Ontario, CANADA

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