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Lowpass filter for CNY70 with arduino

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Hello guys, I´m new using labview and my problem is with an analog signal using a sensor CNY70, actually the problem is only with the noise that the signal have, when I use a potentiometer as an input signal is the same problem.

 

I use arduino and makerhub to make the communication between the sensor and labview, I tried to use a filter but it´s produced an error, the last picture show the noise to the signal.

 

 

1.png2.png3.png

 

 

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You are sending a single value to the Filter express VI.  How do you filter a single point?

 

Get rid of the express VI.  Use a Pt by Pt filter.

 

The error message comes because the scalar gets coerced to the dynamic data type.  Since it has no timing information (and of course no multiple samples to actually filter), the timing is assumed to be dT=1.  Your filter values probably don't match up with that.  With dT of 1, you can only filter 0 to 1/2 Hz.  Your real dT is probably something much smaller, thus much higher frequency, but the coercion of the scalar value can't pass whatever that value is along to the filter VI.

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Thanks for your answer, I´m have no idea how to do the pt by pt filter but I tried with the butterworth and it said that I have a different type of terminal.

 

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Solution
Accepted by topic author Pablochacon

Hard to see since your error message covers the function.

 

Why can't you use Pt by Pt?  Did you search the palettes for it?  I'm guessing, since I can't see it,  that the filter you put in is not Point by Point.

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