Rpi::Dht

Written purly in Ruby (except external gems)!

datasheet references

• dht11
• dht22

Installation

Add this line to your application's Gemfile:

gem "rpi-dht"

And then execute:

$ bundle

Or install it yourself as:

$ gem install rpi-dht

Usage

require "rpi/dht"

pin = 4 # bcm number https://i.gyazo.com/8de74c9e6a7139e30c2f540715a24dc9.png

####################
# GPIO numbering
####################
# RPi::Dht.set_numbering(:bcm)        [default]
# or RPi::Dht.set_numbering(:board)

# Because it can't receive valid data from sensor reliably, there are methods try to read continusly until it gets valid data
# [read_11 and read_22] (without !) are recommended

####################
# for DHT11 sensor
####################
RPi::Dht.read_11!(pin) # raises exception, if you want to manage by yourself
# => returns e.g. {humidity: 12, temperature: 34, temperature_f: 93.2}
# or exception

RPi::Dht.read_11(pin, tries: 50) # tries 50 times and doesn't raise
# or RPi::Dht.read_11(pin) defaults to 50 tries
# => returns e.g. {humidity: 12, temperature: 34, temperature_f: 93.2}
# or nil if it doesn't get valid data

####################
# for DHT22 sensor
####################
RPi::Dht.read_22!(pin) # raises exception, if you want to manage by yourself
# => returns e.g. {humidity: 12.3, temperature: 34.5, temperature_f: 94.1}
# or exception

RPi::Dht.read_22(pin, tries: 50) # tries 50 times and doesn't raise
# or RPi::Dht.read_22(pin) defaults to 50 tries
# => returns e.g. {humidity: 12.3, temperature: 34.5, temperature_f: 94.1}
# or nil if it doesn't get valid data

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/github0013/rpi-dht.