ruby_buzz

ruby-buzz

A Ruby library for controlling the LEDs on buzz controllers in Linux.

• Linux only
• Wired buzz controllers only

Warning: ruby_buzz has to change some rights down in the /sys and /dev folders of Linux in order to access the kernel. You will be asked for your password in order to use ruby_buzz.

Example Scripts

The scripts folder contains examples of the input and output functionality for the buzz controllers.

Turn on buzzer 1

ruby scripts/light.rb 1 on

Turn off buzzer 1

ruby scripts/light.rb 1 off

Watch the inputs

ruby scripts/read.rb

(press ctrl+c to stop)

Pushing the buzzer lights that buzzer

ruby scripts/events.rb

(press ctrl+c to stop)

Using it in your code

Lights

Include the ruby_buzz library

require 'ruby_buzz'

The Buzz controller has 4 pads, each of which has four lights. They can be accessed like so:

# Via the pads
RubyBuzz::Pad[0]
RubyBuzz::Pad[0].light
RubyBuzz::Pad.all
# A control for light 1, divorced from the pad.
RubyBuzz::Light.new(0)

Control one light:

pad = RubyBuzz::Pad[0]
pad.light.on
sleep 1
pad.light.off

A quick light show

RubyBuzz::Pad.all.each do |pad|
  pad.light.on
  sleep 0.1
end 
RubyBuzz::Pad.all.each do |pad|
  pad.light.off
  sleep 0.1
end 

If you abandon your script before all the lights are turned off they will say on indefinitely. You may want to rescue SystemExit and Interrupt errors with RubyBuzz::Light.all_off E.g.

begin
  loop do
    RubyBuzz::Pad[rand(4)].light.on
    RubyBuzz::Pad[rand(4)].light.off
    sleep 0.1
  end 
rescue SystemExit, Interrupt
  RubyBuzz::Light.all_off
end

Button events

Include the ruby_buzz library

require 'ruby_buzz'

The Buzz controller has 4 pads, each of which has four buttons named:

• buzz
• blue
• orange
• green
• yellow

They can be found like this:

RubyBuzz::Pad[0]
RubyBuzz::Pad[0].buttons
RubyBuzz::Pad[0].buttons[:buzz]
RubyBuzz::Pad.all

You can define a block of code to be run by a given button like this:

RubyBuzz::Pad[0].add_event(
  :buzz,
  lambda {
    puts "Player 1 buzzed!"
  }
)

You can debug the actions you've added to a button with trigger_events

RubyBuzz::Pad[0].trigger_events

How about getting it to run when you press the button?

The RubyBuzz::Device class is responsible for reading the raw input from the Buzz controllers via the linux terminal. Because it's reading a data stream, it needs to start a background process to allow it to work while other ruby code is operating.

You can start background process, which executes the events you added to the buttons, with start_watching.

device = RubyBuzz::Device.new
RubyBuzz::Pad.all.each do |pad|
  pad.add_event(:buzz, lambda { puts "Buzz!" }
)
device.start_watching

Note: This process will end when your ruby process ends, but if you want to stop it before that stage, you can call device.stop_watching

If you want to do nothing other than watch the buttons, you may want to follow start_watching with an empty loop.

device = RubyBuzz::Device.new
RubyBuzz::Pad.all.each do |pad|
  pad.add_event(:buzz, lambda { puts "Buzz!" }
)
device.start_watching

loop do

end 

Acknowledgements

This repo includes a modified version of the devinput class from https://github.com/kamaradclimber/libdevinput Which was forked from https://github.com/prullmann/libdevinput