Arduino Uno R4 Led Matrix examples

One of the interesting features of the Arduino UNO R4 WiFi is that it has a built-in 12×8 LED Matrix. Using a bit of creativity you can display anything you want on this.

There is a handy led matrix editor online where you can create your animations, link is at the bottom of this article

To use the LED Matrix library, there are a couple of things that you will need to add to your sketch

First, include the library at the top of your sketch, like this:

#include "Arduino_LED_Matrix.h"

Then, you need to create a LED Matrix object in your sketch, by adding the following line directly underneath the first one

ArduinoLEDMatrix matrix;

And then lastly, you start the LED Matrix by adding this line in void setup():

matrix.begin();

So a basic framework would be

#include "Arduino_LED_Matrix.h"

ArduinoLEDMatrix matrix;

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

void loop() {

}

Now let’s look at 2 examples that you can try, both use slightly different ways to light the less and display animations

Code examples

Example 1

#include "Arduino_LED_Matrix.h"
ArduinoLEDMatrix matrix;

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

uint8_t frame[8][12] = {
  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 },
  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 }
};

void corners()
{

  frame[0][0] = 1;
  frame[0][11] = 1;
  frame[7][0] = 1;
  frame[7][11] = 1;
}

void centre()
{
  frame[3][5] = 1;
  frame[3][6] = 1;
  frame[4][5] = 1;
  frame[4][6] = 1;
}

void clearmatrix()
{
  frame[0][0] = 0;
  frame[0][11] = 0;
  frame[7][0] = 0;
  frame[7][11] = 0;
  frame[3][5] = 0;
  frame[3][6] = 0;
  frame[4][5] = 0;
  frame[4][6] = 0; 
}


void loop()
{
corners();
matrix.renderBitmap(frame, 8, 12);
delay(1000);
centre();
matrix.renderBitmap(frame, 8, 12);
delay(1000);
clearmatrix();
matrix.renderBitmap(frame, 8, 12);
delay(1000);
}

Example 2

#include "Arduino_LED_Matrix.h"


ArduinoLEDMatrix matrix;

const uint32_t frame1[] = {
  0xfff80180,
  0x18018018,
  0x1801fff,
  66
};

const uint32_t frame2[] = {
  0x7fe40,
  0x24024024,
  0x27fe000,
  66
};

const uint32_t frame3[] = {
  0x3f,
  0xc2042043,
  0xfc000000,
  66
};

const uint32_t frame4[] = {
  0x0,
  0x1f81f80,
  0x0,
  66
};

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

void loop() {
  matrix.loadFrame(frame1);
  delay(500);
  matrix.loadFrame(frame2);
  delay(500);
  matrix.loadFrame(frame3);
  delay(500);
  matrix.loadFrame(frame4);
  delay(500);
}

Link

https://ledmatrix-editor.arduino.cc/

https://github.com/programmershelp/Arduino/tree/main/R4%20Examples/matrixexample1

https://github.com/programmershelp/Arduino/tree/main/R4%20Examples/matrixexample2