piled - A web LED controller and client for Raspberry Pi
Written with Node.js
The web component is heroku-ready. The Procfile is suitable for use with foreman or node-foreman. Run locally with
node index.js
SSH to your Pi, update apt-get, install pi-blaster daemon, install autoconf git, node, and npm, and clone piled repo
ssh pi@<ip-of-raspberry-pi>
sudo apt-get update
sudo apt-get install autoconf
wget http://node-arm.herokuapp.com/node_latest_armhf.deb
sudo dpkg -i node_latest_armhf.deb
git clone https://github.com/sarfata/pi-blaster
cd pi-blaster
./autogen.sh
./configure
make
sudo make install
git clone https://github.com/sleighter/piled.git
cd piled/client
## raspberry pi doesn't play nice with https, use insecure registry
npm config set registry http://registry.npmjs.org
npm install
## Default GPIO PIN map
## RED_PIN = 18
## GREEN_PIN = 17
## BLUE_PIN = 19
## pass the server url as a environment variable
PILED_SERVER_URL=ws://<hostname-of-piled-server> node client.js
To set the client to run at start-up, place configuration in conf and copy the piled-service to /etc/init.d/
Sourced from node-startup.
curl -X POST http://<hostname-of-piled-server>/on
# Set color using css color names
curl -H "Content-Type: application/json" -d '{"color":"teal"}' http://<hostname-of-piled-server>/color
# Or hex codes
curl -H "Content-Type: application/json" -d '{"color":"#00FFFF"}' http://<hostname-of-piled-server>/color
# Or an RGB object
curl -H "Content-Type: application/json" -d '{"color":{"r":0, "g": 255, "b": 255}}' http://<hostname-of-piled-server>/color
curl -X POST http://<hostname-of-piled-server>/off
The Pi's GPIO cannot directly power leds, a driver board is required. This Adafruit tutorial provides a good basic design for powering led strip lights.
If building a driver board isn't your thing, or you'd like to make more than a few controlled strips, it's possible to use the mass-produced IR-controlled LED drivers included in many Amazon packages. It is far faster and usually cheaper to buy these units than to build your own drivers. See RGB Strip Controller/Driver. To this end, I have also included a controller module to permit direct control of these units using the IR control input.
The downside is that we are limited by the control set provided by the driver unit. The available controls roughly map to the keys of the included 44-key remote. The fine-grained and parallel control afforded by directly controlling each channel is not available here. Instead, we must control lights as we would with the remote: by choosing preset colors, or individually adjusting the brightness of each channel in large stops. Transitions are therefore less smooth and selection of non-preset colors less reliable.
Since this is a solder-less solution, we will not be opening up the driver unit, nor will we be transmitting IR signals to it. Instead, we will directly wire the RPi to the unit's IR input and simulate IR signals on the wire. We will use lirc-rpi, an IR driver, to produce the signal outputs.
First, cut off the existing IR receiver, making note of the connector wire orientation. With the receiver facing you, the wires are, from left to right: Signal, Ground, Vcc(+5v). Ground and Vcc connect to a Ground and +5v pin of the RPi. Unfortunately, the +5v output from the driver unit is not sufficient to power the RPi, so we will still need two power supplies. One for the driver unit and one for the RPi. Finally wire the signal line to a GPIO pin. Here I chose GPIO 21.
Second, install and configure lirc-rpi. See Setting Up lirc on the Raspberry Pi. We must disable the softcarrier, as this will transmit our signals on a carrier frequency. If you'd like to capture the IR signals yourself, see the note below. For ease, if using the SUPERNIGHT or clone driver unit, you can use the included config file, shared by Raudi here by copying lircd.conf to /etc/lirc/lircd.conf
sudo apt-get install lirc
sudo tee /etc/modprobe.d/lirc-rpi.conf <<EOF > /dev/null
options lirc_rpi gpio_in_pin=22 gpio_out_pin=21 softcarrier=0
EOF
sudo tee /etc/modules <<EOF > /dev/null
lirc_dev
lirc_rpi gpio_out_pin=21 softcarrier=0
EOF
sudo tee /etc/lirc/hardware.conf <<EOF > /dev/null
########################################################
# /etc/lirc/hardware.conf
#
# Arguments which will be used when launching lircd
LIRCD_ARGS="--uinput"
# Don't start lircmd even if there seems to be a good config file
# START_LIRCMD=false
# Don't start irexec, even if a good config file seems to exist.
# START_IREXEC=false
# Try to load appropriate kernel modules
LOAD_MODULES=true
# Run "lircd --driver=help" for a list of supported drivers.
DRIVER="default"
# usually /dev/lirc0 is the correct setting for systems using udev
DEVICE="/dev/lirc0"
MODULES="lirc_rpi"
# Default configuration files for your hardware if any
LIRCD_CONF=""
LIRCMD_CONF=""
########################################################
EOF
sudo echo "dtoverlay=lirc-rpi" >> /boot/config.txt
# reboot
sudo shutdown -r now
# reconnect and test that it works by using irsend to send something
irsend SEND_ONCE led led-green
Note that lirc-rpi includes some awesome utilities for recording signals to create your own IR config files. With a basic breadboard and some lead wires, you can use the IR receiver cut from the driver unit to create an IR input for the RPi. In the example above, you'll note that I configured an input on GPIO pin 20. To use the IR receiver as an input, wire the signal lead to pin 20, and the GND and Vcc leads to the matching pins on the RPi. Review the manual for the irrecord command for more information on capturing IR signals for any remote.
rgbcolor.js - Converts css colors and hex codes to easy-to-use {r:0, g:0, b:0} objects. - Converted to a node module and included in this repo.
pi-blaster.js - Adds PWM to all the Pi's GPIO, allowing us to vary LED intensity
transition.js - Algorithms for smooth color transitions