On Sat, Jun 16, 2012 at 4:10 AM, Electron <electron2k4@infinito.it> wrote:
> On a 3-axial accelerator I compute the magnitude by simple Pythagorean th=
eorem
> in 3D, i.e. Mag=3Dsqrt(AccX*AccX+AccY*AccY+AccZ*AccZ)
>
> It is an analogue accelerometer with significant RC filters between its 3=
 analog
> outputs and the PIC ADC.

What is the range of your AccX, AccY and AccZ values? What value gives
you zero g? What value gives you 1g?

If you are using A/D counts, 0 to 1023, then you need to use an
integer data type and subtract 512 so that for an acceleration of zero
you have an input of zero.
--
Martin K.
--=20
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