Arduino Based Individually Addressable LED Controller with Blynk

Control individually addressable LED's from a smartphone using an Arduino and any device capable of running python scripts using serial communication.

Why?

Prebuilt controllers are a quick and easy way to control individually addressable LED's, but they often lack customizability and are generally unreliable.

This setup provides a seamless way to control the LED's from anywhere in the world using a smartphone, and has over 20 custom effects included.

My desktop is always on so I chose to run the host there, but you can also use a Raspberry Pi as a host without any changes to the application.

Basics

There are three components that need to be in place for the controller to work.

• Linux/Mac/Windows machine running the Blynk python script used as the Master
• Arduino or a similar microcontroller used as the Slave
• Blynk app installed on a smartphone

Setup

Before doing anything, clone this repository and save it to your machine

Let's start this guide by getting the Blynk setup on the smartphone. After downloading the app and making an account, initialize a new project with your respective hardware, and select 'USB' for the connection type. You should now have a blank app and an auth token.

Next, clone my Blynk App by scanning this QR Code inside of Blynk

You should now have the Controller Setup on Blynk, and have a Auth Token emailed to you that will be used in the python script to communicate with your instance of the app.

Lets get the Arduino setup.

controller.ino contains all the custom patterns which will be available on your controller, as well as the logic for receiving commands from blynkmaster.py through Serial USB communication.

If you don't have the Arduino IDE downloaded, download it now. We need to install one package inside the Arduino IDE before we can upload the program.

Open controller.ino in the Arduino IDE and open the Library Manager by navigating to Sketch -> Include Libraries -> Manage Libraries

Install the latest version of FastLed which was created by Daniel Garcia.

There is some setup inside the code with which you need to modify before you can control your LEDS.

In the header:

• #define LED_DT 7 designates which pin will be used as the data pin for the LEDs
• #define LED_CK 11 designates which pin will be used for the clock pin, if any.
  • WS2812 LEDs don't use a clock pin, APA102 LEDs do.
• #define COLOR_ORDER GRB designates the order that your led strip interprets RGB values
  • It should be GRB if you are using WS2812 LEDs, or BGR if you are using APA102 LEDs
• #define NUM_LEDS 150 tells the program how many addressable LEDS are in your strip.
• LEDS.addLeds<LED_TYPE, LED_DT, COLOR_ORDER>(leds, NUM_LEDS);

In the setup method:

You need to decide which of the following methods you need to use in order to initialize your LED strip in FastLED

• LEDS.addLeds<LED_TYPE, LED_DT, COLOR_ORDER>(leds, NUM_LEDS); _This is to be used with WS2812.
• LEDS.addLeds<LED_TYPE, LED_DT, LED_CK, COLOR_ORDER>(leds, NUM_LEDS); _This is to be used with APA102
  • Uncomment the method for your respective LED strip, and comment out the unused one.

You are now ready to upload to the Arduino

• Plug your Arduino into the computer using a USB A-B cable
• Select your board type in Tools -> Board
• Select your port in Tools -> Port
  NOTE: Remember what port you are on, as this will be used in the blynkmaster.py script to initialize serial communication
• Compile and Upload the file to the Arduino

Lets now get the Python Script Setup.

After setting up the Arduino, install the requirements by running the following command in a terminal window inside the repository's folder on your machine to install the python dependencies

pip install -r requirements.txt

Next, open blynkmaster.py in IDLE or your favorite Python IDE and add the AUTH token that was sent to your email to the BLYNK_AUTH variable

#Insert your Blynk Auth Token here
BLYNK_AUTH = 'xZeZ7ZY9pjZ4xqg5iZ3JejE5c69-m4YZ'

Finally, tell the program what port your Arduino is by editing the following variable

ser = serial.Serial('com4', 2400, timeout=1)

'com4' tells where to initialize serial communication for the Arduino, change this to reflect the port that was shown in the Arduino IDE.

You are now ready to begin controlling the LED's

• Plug your LED's data line into the respective port on your Arduino, which as designated in the Arduino Setup Section
• Plug the LED's clock line into the respective port on the Arduino (only required if using APA102 LEDs)
• Make sure your Arduino is plugged into the the host machine, and that the ports are setup correctly
• Run the blynkmaster.py script
• Open the Blynk Project on your smartphone
• You should now be able to control your LEDs though the interface on the app!

Customization

The FastLED library allows for a virtually unlimited number of custom patterns

• In order to add custom patterns, you need to:
  • Add the animation function to the controller.ino file
  • Add a case statement inside the main loop for the new animation
  • Add one the range of the mode widget on the Blynk App
  • Add an elif statement to the @blynk.handle_event('write V2') method in the blynkmaster.py script to change the label for the current mode.

The current patterns on a Arduino Uno only take up a fraction of the max memory, so there is room for many more custom animations.

Contributing

Pull requests are welcome. For major changes, please open an issue first to discuss what you would like to change.