Cylon.js For Raspberry Pi

Cylon.js (http://cylonjs.com) is a JavaScript framework for robotics, physical computing, and the Internet of Things (IoT).

This module provides an adaptor for the Raspberry Pi single board computer (http://www.raspberrypi.org/). It currently works with both the Raspberry Pi & Raspberry Pi 2.

Want to use Ruby on robots? Check out our sister project Artoo (http://artoo.io)

Want to use the Go programming language to power your robots? Check out our sister project Gobot (http://gobot.io).

How to Install

Installing Cylon.js for the Raspberry Pi is easy, but must be done on the Raspi itself, or on another Linux computer. Due to I2C device support, the module cannot be installed on OS X or Windows.

Install the module with:

$ npm install cylon cylon-raspi

How to Use

This small program causes an LED to blink.

var Cylon = require("cylon");

Cylon.robot({
  connections: {
    raspi: { adaptor: 'raspi' }
  },

  devices: {
    led: { driver: 'led', pin: 11 }
  },

  work: function(my) {
    every((1).second(), my.led.toggle);
  }
}).start();

How to Connect

Install the lastest Raspbian OS

You can get it from here: http://www.raspberrypi.org/downloads/

Setting the Raspberry Pi keyboard

Having trouble with your Raspberry Pi keyboard layout? Use the following command:

sudo dpkg-reconfigure keyboard-configuration

Update your Raspbian and install Node.js

These commands need to be run after SSHing into the Raspi:

sudo apt-get update
sudo apt-get upgrade
wget http://nodejs.org/dist/v0.10.28/node-v0.10.28-linux-arm-pi.tar.gz
tar -xvzf node-v0.10.28-linux-arm-pi.tar.gz
node-v0.10.28-linux-arm-pi/bin/node --version

You should see the node version you just installed.

$ node --version
v0.10.28

Once you have installed Node.js, you need to add the following to your ~/.bash_profile file. Create this file if it does not already exist, and add this to it:

NODE_JS_HOME=/home/pi/node-v0.10.28-linux-arm-pi
PATH=$PATH:$NODE_JS_HOME/bin

This will setup the path for you every time you login. Run the source ~/.bash_profile command to load it right now without having to login again.

Thanks @joshmarinacci for the blog post at http://joshondesign.com/2013/10/23/noderpi where these modified instructions were taken.

Connecting to Raspberry Pi GPIO

This module only works on a real Raspberry Pi. Do not bother trying on any other kind of computer, it will not work. Also note you will need to connect actual circuits to the Raspberry Pi's GPIO pins.

In order to access the GPIO pins without using sudo you will need to both app the pi user to the gpio group:

sudo usermod -G gpio pi

And also add the following udev rules file to /etc/udev/rules.d/91-gpio.rules:

SUBSYSTEM=="gpio", KERNEL=="gpiochip*", ACTION=="add", PROGRAM="/bin/sh -c 'chown root:gpio /sys/class/gpio/export /sys/class/gpio/unexport ; chmod 220 /sys/class/gpio/export /sys/class/gpio/unexport'"
SUBSYSTEM=="gpio", KERNEL=="gpio*", ACTION=="add", PROGRAM="/bin/sh -c 'chown root:gpio /sys%p/active_low /sys%p/direction /sys%p/edge /sys%p/value ; chmod 660 /sys%p/active_low /sys%p/direction /sys%p/edge /sys%p/value'"

Thanks to "MikeDK" for the above solution: https://www.raspberrypi.org/forums/viewtopic.php?p=198148#p198148

Enabling the Raspberry Pi i2c on Raspbian

You must add these two entries to your /etc/modules

i2c-bcm2708
i2c-dev

You must also ensure that these entries are commented in your /etc/modprobe.d/raspi-blacklist.conf

#blacklist spi-bcm2708
#blacklist i2c-bcm2708

You will also need to update the /boot/config.txt file. Edit it add the following text:

dtparam=i2c1=on
dtparam=i2c_arm=on

Finally, you need to allow the pi user permissions to access the i2c interface by running this command:

sudo usermod -G i2c pi

Now restart your Raspberry Pi.

Enabling PWM output on GPIO pins.

You need to install and have pi-blaster running in the raspberry-pi, you can follow the instructions for pi-blaster install in the pi-blaster repo here:

https://github.com/sarfata/pi-blaster

Available PINS

The following object depicts available pins for all revisions of raspberry-pi, the key is the actual number of the physical pin header on the board,the value is the GPIO pin number assigned by the OS, for the pins with changes between board revisions, the value contains the variations of GPIO pin number assignment between them (eg.rev1, rev2, rev3).

You should just be concerned with the key (number of the physical pin header on the board), Cylon.JS takes care of the board revision and GPIO pin numbers for you, this full list is for reference only.

PINS = {
  3: {
    rev1: 0,
    rev2: 2,
    rev3: 2
  },
  5: {
    rev1: 1,
    rev2: 3,
    rev3: 3
  },
  7: 4,
  8: 14,
  10: 15,
  11: 17,
  12: 18,
  13: {
    rev1: 21,
    rev2: 27,
    rev3: 27
  },
  15: 22,
  16: 23,
  18: 24,
  19: 10,
  21: 9,
  22: 25,
  23: 11,
  24: 8,
  29: {
    rev3: 5
  },
  31: {
    rev3: 6
  },
  32: {
    rev3: 12
  },
  33: {
    rev3: 13
  },
  35: {
    rev3: 19
  },
  36: {
    rev3: 16
  },
  37: {
    rev3: 26
  },
  38: {
    rev3: 20
  },
  40: {
    rev3: 21
  }
};

The website http://pi.gadgetoid.com/pinout has a great visual representation of this information.

Documentation

We're busy adding documentation to our web site at http://cylonjs.com/ please check there as we continue to work on Cylon.js

Thank you!

Contributing

For our contribution guidelines, please go to https://github.com/hybridgroup/cylon/blob/master/CONTRIBUTING.md .

Release History

For the release history, please go to https://github.com/hybridgroup/cylon-raspi/blob/master/RELEASES.md .

License

Copyright (c) 2013-2015 The Hybrid Group. Licensed under the Apache 2.0 license.