Using a DHTxx Sensor

To test the sketch, we'll use an Arduino. You can use any micrcontroller that can do microsecond timing, but since its a little tricky to code it up, we suggest verifying the wiring and sensor work with an Arduino to start.

Begin by downloading the DHT library from our github repository. To download, click the DOWNLOADS button in the top right corner. Rename the uncompressed folder DHT and make sure that it contains the dht.cpp file and others. Then drag the DHT folder into the arduinosketchfolder/libraries/ folder. You may have to create that libraries sub-folder if it doesnt exist. Restart the IDE.

IMPORTANT: As of version 1.3.0 of the DHT library you will also need to install the Adafruit_Sensor library, which is available from the Arduino library manager:

Now load up the Examples->DHT->DHTtester sketch

If you're using a DHT11 sensor, comment out the line that sets the type:
//#define DHTTYPE DHT22   // DHT 22  (AM2302)
and uncomment the line that says:
#define DHTTYPE DHT11   // DHT 11
This will make the data appear correctly for the correct sensor. Upload the sketch!
You should see the temperature and humidity. You can see changes by breathing onto the sensor (like you would to fog up a window) which should increase the humidity.

You can add as many DHT sensors as you line on individual pins, just add new lines such as

DHT dht2 = DHT(pin, type);

below the declaration for the initial dht object, and you can reference the new dht2 whenever you like.

Last updated on 2017-10-30 at 04.48.05 PM Published on 2012-07-29 at 11.58.38 AM