DHT air temperature and humidity sensor

Open sensor datasheet

Implementation using LIFA

Install everything you need to interface LabView with Arduino.

NOTE: After you follow the steps to install LabView support for Arduino, you will need to upload the LIFA_Base firmware into your Arduino board. The normal version will not support the DHTxx sensor, but you can find a modified version in the LIFA DHTXX LV09 RevB.zip file that you can download below. Also, in order to make this work, use the Arduino IDE 1.0.5 version that you can get from here, with a windows installer. To upload the LIFA_Base firmware open the Arduino IDE 1.0.5 version, open the LIFA_Base file located in ...CustomFirmware/LIFA_Base and press Upload. See this forum if you have problems. If the Arduino IDE doesn't load in Windows 7 you might have Java problem.

The LIFA DHTXX LV09 RevB.zip file also contains example VIs that you can use to build your sensing applications.

You can already take a look at the DHT11 Example.vi that you can download below.

Pin connections

1. VCC (3 to 5V power)

2. Data out

3. Not connected

4. Ground

Simply ignore pin 3, its not used. You will want to place a 10K resistor between VCC and the data pin, to act as a medium-strength pull up on the data line. The Arduino has built in pullups you can turn on but they're very weak, about 100K

This diagram shows how we will connect for the testing sketch. Connect data to pin 2, you can change it later to any pin.