Humidity Sensing

DHT Humidity Sensing on Raspberry Pi or Beaglebone Black with

GDocs Logging

Created by lady ada

Last updated on 2015-04-26 02:30:10 PM EDT

Guide Contents

Guide Contents

Overview

Wiring

Wiring up DHT humidity sensors

Raspberry Pi

Beaglebone Black

Software Install (Updated)

(http://adafru.it/dCK)Downloading the Code from Github

Installing the Library

Testing the Library

C Language Code

Connecting to Googles Docs (Updated)

Create and prepare spreadsheet

Get OAuth2 credentials

Run Python Code

© Adafruit Industries

https://learn.adafruit.com/dht-humidity-sensing-on-raspberry-pi-withgdocs-logging

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Overview

This tutorial is a first attempt to develop a DHT interface driver. It is not guaranteed to work,

and is for experimentation and hacking!

Time to start exploring more sensors with the Raspberry Pi and Beaglebone Black! Today we'll be

checking out the DHT11 (http://adafru.it/386), DHT22 (http://adafru.it/385) and

AM2302 (http://adafru.it/393) humidity and temperature sensors available from Adafruit

In this tutorial we'll be showing how to install a DHT sensor Python library which utilizes C for highspeed GPIO polling to handle bit-banged sensor output. Many low cost sensors have unusual

output formats, and in this case, a "Manchester-esque" output that is not SPI, I2C or 1-Wire

compatible must be polled continuously by the Pi to decode. Luckily, the C GPIO libraries are fast

enough to decode the output.

Once we have that working, we add the fun of Python to update a google spreadsheet live with the

temperature/humidity data. This project would be the great basis for home or garden automation!

You can check out our spreadsheet here, it wont be updated live after Aug 24 2012 but it will show

© Adafruit Industries

https://learn.adafruit.com/dht-humidity-sensing-on-raspberry-pi-withgdocs-logging

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you the format of data you get...