Arduino UNO R4 WiFi LED Matrix Tool

The Arduino UNO R4 WiFi has a vibrant 12×8 LED matrix for creating visual patterns, animations, and more. To help you design and implement custom patterns for the LED matrix, we’ve developed a tool that simplifies the process.

 This guide will walk you through how to use the tool and then incorporate your designs into an Arduino project using the Arduino_LED_Matrix.h library.

Features of the Web Tool

1. Interactive Grid Interface:
   • A 12×8 grid representing the LED matrix.
   • Each cell corresponds to an individual LED, and you can toggle it on or off.
2. Live Code Generation:
   • Automatically generates an Arduino-compatible byte array based on your design.
3. Export and Import Functionality:
   • Save your matrix designs as JSON files for future use.
   • Load previously saved designs back into the tool.
4. Visual Preview:
   • See your LED pattern instantly as you create it.

Step-by-Step Guide

1. Access the Tool

You’ll see a 12×8 grid of clickable cells representing the LEDs on the Arduino UNO R4’s matrix.

2. Create Your Pattern

• Click on any cell to toggle its state:
  • Green: The LED is turned on.
  • Gray: The LED is turned off.
• Modify the grid until your desired pattern is complete.

3. Copy the Generated Code

• As you create your pattern, the tool generates the corresponding C/C++ code in the following format:

byte frame[8][12] = {
  { 0, 0, 1, 1, 0, 0, 0, 1, 1, 0, 0, 0 },
  { 0, 1, 0, 0, 1, 0, 1, 0, 0, 1, 0, 0 },
  { 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0 },
  { 0, 0, 1, 0, 0, 0, 0, 0, 1, 0, 0, 0 },
  { 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0 },
  { 0, 0, 0, 0, 1, 0, 1, 0, 0, 0, 0, 0 },
  { 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0 },
  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }
};

• Copy the code directly from the tool’s output field.

4. Save or Load Patterns

• Export: Click the export button to download your design as a JSON file.
• Import: Load a previously saved design by selecting the JSON file via the import button.

Integrating with Arduino

To use your generated pattern on the Arduino UNO R4, we recommend the Arduino_LED_Matrix.h library. Follow these steps to bring your pattern to life:

1. Install the Library

• Open the Arduino IDE.
• Go to Sketch > Include Library > Manage Libraries.
• Search for Arduino_LED_Matrix and click Install.

2. Setup the Hardware

Ensure your Arduino UNO R4 WiFi is powered and the LED matrix is properly initialized. The library handles all low-level configurations for you.

3. Upload the Code

Use the following example code to display your pattern:

#include <Arduino_LED_Matrix.h>

ArduinoLEDMatrix matrix;

byte frame[8][12] = {
  { 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0 },
  { 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0 },
  { 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0 },
  { 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0 },
  { 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0 },
  { 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0 },
  { 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0 },
  { 0, 1, 1, 0, 0, 0, 0, 0, 0, 1, 1, 0 }
};

void setup() {
    matrix.begin();
    matrix.renderBitmap(frame, 8, 12);
}

void loop() {
    // Add animations or additional logic here
}

You can also use a hexadecimal output by checking the box in the tool. This will reduce memory usage because you are now using a 32-bit variable instead of several bytes.
This code will produce the same glyph as the code above:

#include <Arduino_LED_Matrix.h>

ArduinoLEDMatrix matrix;

unsigned long frame[] = {
  0x60660660,
  0x67fe7fe6,
  0x06606606
};

void setup() {
    matrix.begin();
    matrix.loadFrame(frame);
}

void loop() {
    // Add animations or additional logic here
}

4. Modify and Test

• Upload the sketch to your Arduino.
• Observe your custom pattern light up on the LED matrix!

Tips and Tricks

• Animations: To create animations, define multiple frame arrays and cycle through them in the loop() function.
• Brightness Control: Use the library’s brightness functions to adjust the LED intensity.
• Dynamic Patterns: Combine inputs like buttons or sensors to dynamically modify the displayed pattern.

With this tool and guide, you can easily design and program patterns for your Arduino UNO R4’s LED matrix. Have fun experimenting, and bring your ideas to light!