Need a stable reading

JB

I am using BS2 and ADC0831.
I have attached my code herewith which I got from the manual.

I just want a stable reading coming out of the A/D. I can see a voltage representation as well as 8 bits binary representation of the analog input I am using but my readings seen on debug screen are fluctuating like anything.

I assumed that the reading out of the ADC would display simply the amplitude voltage of the analog input which is what I am looking for.

I need to send the 8 bits binary data to Labview and am displaying a digital value in there.

Any advice please.

allanlane5

I think you need to leave the default state of the 'CS' high -- but I could be wrong.

Also, doesn't it take some time for the ADC to make its reading? Are you giving it that time?

And do you have a common ground?

Newzed

JB, add a .1uf bypass right at your ADC input, and put a 1K resistor in series with your temp sensor.

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4 digit serial LED

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achilles03

Yeah, I think Allanlane is right... you need to leave the CS high for a bit. Put a few "pause 5" statements in there (like after high CS and again after low CS). I had another ADC that had problems until I put in a few pause statements.

Dave

JB

I tried putting a .01 microF Cap as well as 1K resistor. That does not help.

I also tried keeping the CS high and that gives 11111111 and 5V reading.

The code I attached has been retrieved from the manual so I know it is right.

I am however not able to get a stable reading for the output coming out of A/D.

Can someone please help.

JB

Tried putting PAUSE 5 after HIGH CS and LOW CS.
That does not change the fluctuations.

JB

Thanks guys. I figured it out.

I had my Temp Sensor on separate board and my BS2 on separate board. And though both of them were grounded, they didnt have common ground.

Thanks alot for your help.