DHT11

[Morvy187]

thanks man i appreciate your concern.........a small question sensors DHT11/DHT22/RHT03 all do have the same confg 4 pins so there is no difference right ?they are from the same company the only differents that i know are the percison and accuracy ....

[Nathan_B.]

The RHT03 is not the same company that makes the DHTxx sensors according to the datasheets but it looks like it is the same communiction protocol.

[Nathan_B.]

Ok, I've updated this to allow you to specify the pin to use and updated the custom firmware to use the latest version (2.2.0.79).  Please let me know if you are able to get it working.

EDIT:  Updated 2013-03-21

[Morvy187]

ok first of all thank you so much .....let me check my wiring with you i am wiring the sensor like this photo ok but using a 10k Rsistance so tell me if there is something that i need to change first ......and for the example u mad i did run it (Error 5003 occurred at DHT11.lvlib:Read Data.viLabVIEW Interface for Arduino.lvlib:Init.vi.  A timeout occurred while trying to read form the Arduino. ) and this error shows up ihave seen it b4 .....but just first check the wiring and the Rsistance that am usuing and tell me

[Nathan_B.]

Honestly I can't tell you more than what already exists online about the DHT11 library for Arduino.  I always recommend using the example Arduino code (without LabVIEW) that is provided with the library to make sure that it is communicating correctly (meaning you have it hooked up correctly).  If I had one of these sensors to try then I would obviously have more information but unfortunately, I don't have one.

[Morvy187]

OK .....let me till you what i have done am using the similar sensor the RHT03 and already hooked up correctly with arduino and works fine with arduino code, got the Temp read and the Hiumidity also so my connection are right but i thought u do have any other ideas about connection .... ok let me try something and get back to you...........if i wanna change the collecting period from 1sec to 2 sec where can i change it in the LIFA code  just point to me and thank u very much again for your effort

[Nathan_B.]

Ok, so you got it working with Arduino code alone, does my library that I posted work with it?

To poll the sensor slower you can add a delay in your LabVIEW loop.  If this is not practical (i.e. you need the loop to run faster than the rate at which you want to retrieve data) then you will need to put the DHT11 VI in a conditional structure and only allow it to execute if 2 seconds has passed since it was last executed.

[Morvy187]

   // Reading temperature or humidity takes about 250 milliseconds!

  // Sensor readings may also be up to 2 seconds 'old' (its a very slow sensor)

this lines are in the arduino code that works with me can did you follow the same timing in the IC2 block ?

and i did attached the working arduino code

[Nathan_B.]

What is "IC2"?  I didn't write anything in the DHT11 library so I don't know anything about any timing.  Also, I can't and won't open .rar files.  If you need to create an archive for the files, please use a .zip file (because everybody running Windows can open them).

[Morvy187]

ohhh sorry you mean the labview library i didn`t add how do i add it ??

imean I2C block u name it DHT11

i did run the Example you made but it gives me timeout error(5003)