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[on:]

Hello All,

I have question about Analog Input. I am using CD4067Be Mux.  

The analog signal to the arduino input is not stable at all.

Do you have any idea to make it stable? (I am using 10K pot. and, I ordered 50K and 100K pot. Can Bigger potentiometer make it stable?)

I tried Analog input smoothing with average value.. But...it is not working...

I am happy give me any idea....

I am also thinking about Rotary Encoder instead of Pot. What do you think about it?(need a led bargraph or ring Led..It will be another pain)

Thank you in advance..

I hope to hear from you.

[Reply #1 on:]

The analog signal to the arduino input is not stable at all.

I assume you mean the Arduino's readings are not stable. If the source of the signal is not stable an Arduino cannot change it.

Do you have any idea to make it stable?

Do multiple readings and average them, be sure to use datatypes that can hold the sum. Also an often used practice is to do 2 measurements an ignore the first...

I tried Analog input smoothing with average value.. But...it is not working...

try - http://www.arduino.cc/playground/Main/Statistics - or - http://arduino.cc/playground/Main/RunningAverage

I am also thinking about Rotary Encoder instead of Pot. What do you think about it?

I think nothing as I don't know what your goal is.

[Reply #2 on:]

What readings are you getting from the analog to digital converter?

how did you connect the AD? What voltage reference are you using? How are you powering your board? What board is it?

A rotary encoder can work to create a kind of potmeter to be fed into a circular bargraph, although it will take a bit more than a potmeter and also won't have a reference value to start with.

[Reply #3 on:]

Can you show us a wiring drawing of how you are attaching the pot to power, ground and the arduino pin?
One can expect a count value of +/- minus a few counts, so what variation are you seeing?

 Going to a larger pot value will not help.

Lefty

[Reply #4 on:]

Thank you so much All!!!

I do not know how to draw wiring... but, I can explain detail wiring.

I am using Arduino Duemilanove and Using USB as a power.

Digital Output 4,5,6,7 connect to CD4067Be control pin and 16 potentiometer(which is connected to ground and power) connect to each MUX input.

Mux output connect to Analog Pin 0.

I am using 10K potentiometer. It is my first Arduino project and harder than I thought. Fun, Though~

Thank you in Advance.