Raspberry Pi Relay & APA102 LED controller allows control & switching of APA102 addressable LED strips (and LED driver) using a web GUI. Motor controller functionality is also built-in to control hard-wired home automation type blind / projector screen motors. Ideal for use in home cinema applications. Unlike regular "dumb" RGB strips, addressable strips have independently controlled LEDs, allowing for the creation of light effects & sequences. Project details available on GitHub here: https://github.com/plasmadancom/Raspberry-Pi-Relay-APA102-LED-Controller

Step 1: Raspberry Pi Relay & APA102 LED Controller

Raspberry Pi Relay & APA102 LED Controller

Raspberry Pi Relay & APA102 LED controller allows control & switching of APA102 addressable LED strips (and LED driver) using a web GUI. Motor controller functionality is also built-in to control hard-wired home automation type blind / projector screen motors. Ideal for use in home cinema applications. Unlike regular "dumb" RGB strips, addressable strips have independently controlled LEDs, allowing for the creation of light effects & sequences.

Features

• APA102 LED control
• 2x changeover relay control
• 2x mains AC input detection
• Motorised blind / projector screen control
• 2x TTL inputs for external buttons

Motivation

This project was created for use in my own home cinema build. I wanted a single-room home automation solution that would offer addressable RGB control, with the ability to directly switch a mains AC powered LED driver. Additional relay channels where added to the prototype to allow other circuits to be switched using the controller, such as spotlights. The motorised blind control relays were added into the design during my home cinema build.

Home cinema build log: https://www.avforums.com/threads/ongoing-plasmadans-living-room-cinema-office-build.1992617/

Responsive Web GUI

The GUI includes controls for the changeover relay channels, motorised blind / projector screen, a full RGB color picker for the APA102 LEDs and a preset control to cycle built-in light modes / effects. There is also the ability to reboot the Raspberry Pi directly from the GUI, making development & testing easier for your application.

Built on bootstrap 3; the GUI is fully responsive and adapts to any screen size / orientation.

App Features

As well as support for mobile devices, the GUI includes modern manifest data to allow it to work more like a native app. This means when you save the GUI to the home-screen it will load & function without an address-bar, just like an app.

Chrome Extension

The specially created Chrome extension makes the web GUI even easier to use on desktop, allowing for GUI control without the need to leave the current web page. The Chrome extension also provides the ability to map keyboard shortcuts to each function of the web GUI, including toggle on / off, LED preset & blind control.

https://chrome.google.com/webstore/detail/apa102-led-controller/jnmjhaaahpdapgcddlgaldjhapmoapje

Prerequisites

Raspberry Pi with Raspian: https://www.raspberrypi.org/downloads/raspbian/

I recommend a clean Raspian install before proceeding.

Dependencies

APA102 LEDs require the Python port of the Adafruit DotStar library to function. This is included in this repo for completeness.

https://github.com/adafruit/Adafruit_DotStar_Pi

Build Your Own!

The hardware for this controller is quite simple, all the components are readily available. If you decide to build one for yourself, I have provided the necessary Gerber files for the PCB. These can either be sent to a PCB manufacturer like PCBway, or you can etch the board yourself (see included transfer pdf). The PCB design is single-sided to make it easier to re-create yourself. The PCB was designed to fit into a small case (CAMDENBOSS 7200-269C). If you require additional inputs / outputs, or want to make any other changes; you may want to create your own PCB instead.

Parts list: https://goo.gl/5SdG7h

Alternatively you can buy a PCB or complete controller from me. Contact me on AV Forums here.

Just The Basics

If all you want is LED control via Raspberry Pi, you can do this without a PCB. The circuit diagram below shows how to connect APA102 LEDs to a Raspberry Pi using a 74AHCT125 - Quad Level-Shifter. You will still need an LED driver to power the LEDs. The LEDs must share a common-ground with the Raspberry Pi & LED driver.

Stackable

The PCB can easily be stacked using standoffs. The CAMDENBOSS 7200-269C enclosure is tall enough to accommodate two stacked boards. So if you require more channels; this is a simple solution.

Raspberry Pi Compatibility

• All except the original Model B (rev. 1) - Although with some changes it can be made to work.

The PCB design uses a 26-way header (same as the Raspberry Pi model B). A 26-way to 40-way ribbon cable will be needed to work with Raspberry Pi B+ and above.

Wiring

The controller is designed to work with 4-wire type addressable LED strips; such as APA102 (AKA Adafruit DotStars) or WS2801. Everything else on the controller is pretty-much universal in terms of wiring options. I have provided an example wiring diagram:

In this example, the LED driver and halogen lighting circuits are linked to the changeover relay channels. This allows for standard 2-way / intermediate (3-way if you're outside the UK) light switches to be used in conjunction with the controller. This means that if the controller went offline for whatever reason, your lights will still work!

Notice in the example that the switched-line is looped back into the AC detect circuits. This is to allow the Raspberry Pi to sense when the lights / LED driver are powered, regardless of relay / switch positions. If you don't require 2-way control you can disable this in the config.

Installation

sudo bash

Update Raspian

apt-get update
apt-get upgrade

Install Apache components

apt-get install apache2 php5 libapache2-mod-php5

Install WiringPi

apt-get install git-core -y

Get repo

git clone git://git.drogon.net/wiringPi

Build WiringPi

cd wiringPi
git pull origin
./build

Install python-dev & pip

apt-get install python-dev python-pip -y

Install WiringPi

pip install wiringpi2

Enable SPI

Needed for RGB LEDs to work.

raspi-config

Scroll to "Advanced Options", "SPI", set to enabled.

Clone Repo Contents

cd /var/www/html

Empty default Apache files

rm -rf *

Clone repo

git clone https://github.com/plasmadancom/Raspberry-Pi-Relay-APA102-LED-Controller .

Be sure to set file permissions to 755 in the web directory.

chmod -R 755 /var/www

Apache requires sudo permission to use WiringPi. Note: If your Raspberry Pi is on a shared network you may want to find a more secure method than this.

echo "www-data ALL=(ALL) NOPASSWD: ALL" >> /etc/sudoers

To make the Python scripts run at startup, edit rc.local:

nano /etc/rc.local

Add before exit 0

python /var/www/html/python/motor.py&
python /var/www/html/python/preset.py&

The scripts are independent from each other to allow you to just use what you need.

Optional: install vsftpd for easier file editing

apt-get install vsftpd -y

Change user for vsftpd

chown -R pi /var/www

Edit vsftpd.conf

nano /etc/vsftpd.conf

Uncomment the following line:

write_enable=YES

Add the following line:

force_dot_files=YES

Restart vsftpd

service vsftpd restart

Config

There are lots of user customisable options in the config file :/python/config.py Edit the config options as required.

License

MIT © Dan Jones - PlasmaDan.com