Quote Originally Posted by richard View Post
that works out pretty nicely every adc 100 count is almost exactly .01 psi

0=110 , 0.07 = 820 couldn't be easier


assuming I read the data sheet properly and that 0.07 psi = 4.0 volts and vref=5 v of course
Not quite Richard. In theory

0=102.4 at 0.5 volts and 0.07=921.6 at 4.5 volts.

assuming as you say the vref=5 v.

102.4 is the zero offset and 0.07/(921.6-102.4) is the slope.

to convert to psi

psi=(reading-offset)*slope

psi=(reading-102.4)*0.07/819.2

psi=(reading-102.4)*0.0000854492.....

I do seem to remember this is for a depth gauge on a model submarine and am wondering what depth of water is 0.07 psi. The answer is 100 mm of water (99.54mm).

Giving

mm of water=(reading-102.4)*0.12207028.....

just to check at maximum reading = 921.6

therefore

mm of water=(921.6-102.4)*0.12207028

mm of water=99.9999

I am now wondering if this gauge is suitable?