Ruby code for controlling NeoPixels attached to a Raspberry Pi.

Yes.

Install the gem on your RaspberryPi, and copy the strandtest.rb file to your home directory:

sudo gem install pixel_pi
cp `gem contents pixel_pi | grep strandtest.rb` .

Edit the LED_COUNT and LED_PIN at the top of the file to match the NeoPixel circuit attached to your RaspberryPi (read the RaspberryPi NeoPixel guide from Adafruit for all the details). Now run the strandtest example:

sudo ruby strandtest.rb

Enjoy the blinken lights!

Yes it will.

The ws2811 driver is using direct memory addressing (DMA) via /dev/mem to control the NeoPixels. Only the root user has permission to read and write to this hardware device. So any time your work with NeoPixels, your code will need to be run as the super user.

If you want to contribute to this gem then you will need a development environment setup on your RaspberryPi. You will need the ruby headers installed locally.

sudo apt-get install ruby ruby-dev

Install some ruby gems.

sudo gem install rake
sudo gem install rake-compiler

The rake-compiler gem might not install properly. The problem is a very strict requirement on the rubygems version. To work around this we need to download the source code, create the gem by hand, and install. You can skip this step if rake-compiler installed successfully.

sudo su
git clone https://github.com/luislavena/rake-compiler.git
cd rake-compiler
rake gem
gem install pkg/rake-compiler-0.9.3.gem --no-rdoc --no-ri
cd ../
rm -fr rake-compiler
exit

Now we can compile the NeoPixels ruby library.

rake compile

Take a look at the examples/strandtest.rb file and adjust the LED_COUNT and LED_PIN to match your circuit. Run the strandtest and bask in the glow of blinking rainbow lights.

sudo ruby examples/strandtest.rb