# Overview

How to Display on 8×8 Dot Matrix LED Using Arduino(UNO). In this project, we will learn how to use 8×8 dot matrix LED module with Arduino. At the end, you’ll be able to display any shape or text on one or more Dot matrix easily, fixed or scrolled, using Arduino.

## Objectives

• What is dot matrix LED
• How to use Dot matrix LEDs with Arduino
• Displaying specific shapes on a Dot matrix LED module
• Cascading two Dot matrix LEDs

### What Is Dot Matrix?

A  dot matrix LED is simple an array of large number of LEDs together on we  can display whatever we want such as certain numbers, pattern and shapes by just blinking  LED according to certain pattern. IN a Dot Matrix LED  the number of matrices are determined by simply the number of  columns and rows in that matrix. Although the dot matrix LED comes in different type but the most common and one which we are using in this project is dot matrix LED 8×8 which have 64 matrix mean 8 rows and 8 columns. In order to connect dot matrix LED with circuit we simply connects all the rows and columns with the digital pins which give us 16 connection in case of 8×8  dot matrix but this is wrong way of connection. In general a module called MAX72xx ICS are used for dot matrix LED circuit connection  the benefit of doing this that  we  need to connect to 4 digital pins instead of 16. You can also connect multiple Dot Matrix (up to 8) to each other without needing any extra pin and cascades them.

### Connection of Circuit?

In order to display certain pattern or shapes on dot matrix LED we simple connect it with the Arduino board the connections are so simple.

1. First of connect the Vcc pin of matrix with the 5v pin of Arduino
2. Now connect the GND pin of both Arduino and dot matrix together

In the last connect Din and CLK pin of dot matrix with any of the digital pin of Arduino board.

Code for DOT Matrix display using Arduino

Now here we are going to write the cod for dot matrix on Arduino for this purpose first we have to install the libraries for dot matrix .There are various libraries for Dot matrix and Arduino. The Ledcontrol and MaxMatrixlibraries are two of the most common libraries, both have the same structure and we are using the in our project

#include <MaxMatrix.h>

int DIN = 7;

int CLK = 6;

int CS = 5;

int maxInUse = 1;

byte buffer;

char text[] = “a”;

MaxMatrix m(DIN, CS, CLK, maxInUse);

void setup()

{

m.init();

m.setIntensity(8);

}

void loop()

{

m.setDot(0, 7, true);

m.setDot(0, 7, true);

delay(1000);

m.setDot(7, 0, true);

delay(1000);

m.setColumn(3, B11110000);

delay(1000);

m.setColumn(4, B00001111);

delay(1000);

m.clear();

delay(1000);

}

### Display of Shape on Dot Matrix

In order to display  a certain shape on our dot matrix  we simply connect the Arduino board which is already connected to our dot matrix to our computer then after that we upload a certain code on our Arduino board which display the shape on matrix .the following code given below display a shape of face #include <MaxMatrix.h>

int DIN = 7;

int CLK = 6;

int CS = 5;

int maxInUse = 1;

MaxMatrix m(DIN, CS, CLK, maxInUse);

byte poker[] = {8, 8,

0xff,

0x81,

0xa5,

0xa1,

0xa1,

0xa5,

0x81,

0xff

};

byte smile[] = {8, 8,

0xff,

0x81,

0xb5,

0xa1,

0xa1,

0xb5,

0x81,

0xff

};

0xff,

0x81,

0xb5,

0x91,

0x91,

0xb5,

0x81,

0xff

};

byte kiss[] = {8, 8,

0xff,

0x81,

0xb5,

0xb1,

0xb1,

0xb5,

0x81,

0xff

};

void setup() {

m.init();

m.setIntensity(8);

}

void loop() {

m.writeSprite(0, 0, smile);

delay(1000);

m.clear();

m.writeSprite(0, 0, poker);

delay(1000);

m.clear();

delay(1000);

m.clear();

m.writeSprite(0, 0, kiss);

delay(1000);

for (int i = 0; i < 8; i++) {

m.shiftLeft(false, false);

delay(300);

}

m.clear();

}Output:

The above code will display the following shape on our Dot Matrix.