[[Image(humVera.png, align=right, width=400px)]]
= Temperature and Humidity sensor (DHT11/DHT22) =

== Software ==
You can download the Arduino sketch here:\\
http://code.mios.com/git_public/mios/arduino-sensor.git/tree/HEAD:/VeraArduino/Arduino/libraries/Vera/examples/HumiditySensor?js=1\\

This sensor sleeps most of the time. You can change the sleep interval by updating SLEEP_TIME define at the top of the file. 

== Wire things up ==
[[Image(dht22.jpg, align=right)]]

Follow the instructions in ConnectingRadioModule to connect radio module.

To connect the DHT22 sensor to the Arduino board follow these instructions:\\
Pin1. Connect VCC of the DHT22 sensor to +5V\\
Pin2. Connect Data to digital pin 3 of the Arduino board\\
Pin3. Not used.\\
Pin4. Connect to Ground\\
\\
Use also need a pull up resistor between +5V and Data. See picture below.\\

== Hardware - Purchase guide ==

To build this sensor you'll need one arduino + radio specified in the base kit found here:\\
http://code.mios.com/trac/mios_arduino-sensor/wiki/WikiStart#Buyingguide\\
With the following additional parts:

1x DHT22 Temperature and Humidity sensor (there also exist a cheaper humidity sensor called DHT11 that is less accurate but half the price).\\
http://www.aliexpress.com/item/1pcs-DHT22-digital-temperature-and-humidity-sensor-Temperature-and-humidity-module-AM2302-replace-SHT11-SHT15-Free/1031321543.html

TOTAL SENSOR PRICE: $7.6 (arduino + radio) + $5 (DHT22) = '''$12,6'''

[[Image(hum.jpg, width=500px)]]