I bought a cheap DHT22 humidity and temperature sensor module from eBay. It comes with the jumper wires you need and, as far as I can tell, it doesn’t require a resistor, meaning you don’t have to mess around with a breadboard. The benefit of this is that it comes ready to plug straight onto your GPIO pins.
I connected the sensor to my Pi (+：VCC, OUT：data port, -：GND) and used the instructions from Adafruit to get it recording the data and adding it to a Google Spreadsheet. I changed the Python code to update my spreadsheet every five minutes. You can make a nice chart from this but the charts available don’t automatically expand the range if you add more data (i.e. if your Pi is updating the spreadsheet every few minutes). You have to use Script Editor if you want to make a chart from a dynamic range. Also, I found that Google Drive on my Nexus phone doesn’t display charts, so if I wanted to be nerdy and check my chart at any time of day, I couldn’t.
I created a GitHub Page as it looked like a quick way of making a website. It was! Then it was easy to use the Google Chart API to make a line chart for my site. This now shows the most up-to-date readings from my Pi sensor (provided I have my Pi turned on): http://abbie2020.github.io/
I dug out an old webcam for a ‘photobooth’ idea. The user is updated with what’s happening by the LCD display. Continue reading →
Dashing allows you to make beautiful customised dashboards. I’ve got to the point of it being up-and-running and displaying a dashboard in my browser. Next task is to customise it!
How I got Dashing installed and running
$ sudo apt-get install libyaml-ruby
$ tar -xvzf /boot/rubygems-1.8.25.tgz
~/rubygems-1.8.25 $ sudo ruby setup.rb
$ sudo apt-get install ruby1.9.1-dev
$ sudo apt-get install nodejs
$ sudo gem install bundler
$ sudo gem install dashing
Create new dashboard:
$ dashing new Abbies_dashboard
$ cd abbies_dashboard
~/abbies_dashboard $ bundle
Start dashing server:
~/abbies_dashboard $ dashing start