Analog input Read

Octave
#1

I setup the I/O2 as analog input :

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So, 10V on the I/O, the output value must be 1000.

When I apply 9V; the value is 160,7

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With 4,5V on input, the value is 67,7

I use FX30S with the firmware 3.1.0.

Why the value is not good ?

Thank you,

Romuald

#2

Hi Romuald,

It appears there is a bug where Octave is not taking into account that fact that the FX30 IO2 pin has hardware scaling on the ADC. The range of the actual ADC without the hardware scaling is 0V - 1.7V.

Until this is resolved, you can use this fact to calculate the scaling coefficients:

a1 = 1000mv / 1700mV ~= 0.58

Some fine tuning of the coefficent may be needed to match your hardware. This is working on my FX30:

0 - 10 V reports approximately 0 - 1000mV

Thanks,
Ian