LM35+Arduino

[Chintha]

Hello all,,,

I have done a project that reads temperature(LM35) data serially from arduino and displays as a graph and array

JohnCS said:

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Your problem was in the LabVIEW VI  In the VI TempMon2.vi, did you change the first Pattern to Match (which is labeled as "Search for text pattern containing temp reading" )  to match to this?

\r\n[0-9]+\.[0-9]+\r\n\r\nA

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So i followed the  suggenstion and got the output but not the desired.

I am attaching the arduino code and vi's

My problem is i am not getting the correct temperature values,,

Just see NIsolution.jpg attached ,, it is reading room temperature values as 12deg centigrade

Is it the fault of sensor or conversion used in program ?

Also can anybody describe the TempMon2.vi Block diagram,,,

Whats the need for string cancatenation and matchers and all ,, why dont we read temperature values as numbers?

[JohnCS]

You have three separate threads running with what appears to be the same topic. Now you just started another one. Please use only one thread.

JohnCS

[JohnCS]

It looks to me like there is a problem in scaling the analog voltage to temperature. Since we don't know what you or the original author did on your shields for signal conditioning, I can't verify this. But with an analog voltage reported as 72 in your example and 3.3 volt reference, I get 23.2 C.

Check out the Lady Ada Tutorials on the LM35 on Arduino.

JohnCS

[Chintha]

Sorry boss,, someone advised me go for new thread if u mark the solution button ,, sorry anyhow

[Chintha]

By the way ,, what do u mean by kudos,,, its just like voting or what?

[Chintha]

hey i am getting the same ,,, that too negative temperature values,,

I am attaching references,,, I am using 5V arduino deumilnove ,,,

this is is the reference :http://www.ladyada.net/learn/sensors/tmp36.html

[JohnCS]

The app from Lady Ada is for a LM36 which has a 500 mv offset. You have LM35 which does not. When calculating the temperature do not subtract 0.5 volts. Did you read the data sheet? 

JohnCS

[Chintha]

i will try with it,, thanx

[Chintha]

Hi even if i remove 0.5 for LM35 i am getting wrong results as 34deg cent,, and voltage as 0.34

[JohnCS]

How is your LM35 wired to the Arduino? Give the pin numbers used and any other circuitry you have in the system. What is the temperature you expect to see? 

JohnCS