Create a stunning scrolling LED display using MAX7219 dot matrix modules! This project teaches you how to chain multiple 8x8 LED matrices together, display scrolling text, create custom animations, and build eye-catching signs for your home, shop, or maker space. Perfect for notifications, clocks, or decorative displays.
The MAX7219 is a brilliant chip that makes driving LED matrices easy. It handles all the multiplexing internally, so you only need 3 data pins from your Arduino to control hundreds of LEDs. Even better, you can daisy-chain multiple modules for longer displays.
In this project, you'll learn to use the MD_Parola library to create smooth scrolling text, custom fonts, and even simple animations. Whether you want a desk clock, a notification display, or a shop sign - this project has you covered.
| Part Name | Qty |
|---|---|
| Arduino UNO | 1 |
| MAX7219 LED Matrix Module (4-in-1) | 1-2 |
| Jumper Wires (Female-Female) | 5 |
| 5V 2A Power Supply (Optional) | 1 |
The MAX7219 simplifies LED matrix control through serial communication:
VCC: Connect to 5V (use external power for multiple modules)
GND: Connect to Arduino GND
DIN: Data In - connect to Arduino pin 11 (MOSI)
CS: Chip Select - connect to Arduino pin 10
CLK: Clock - connect to Arduino pin 13 (SCK)
Each 8x8 matrix can draw up to 300mA at full brightness. For multiple modules or high brightness, use an external 5V power supply instead of Arduino's regulator.
Open Arduino IDE Library Manager and install both "MD_MAX72XX" and "MD_Parola" by MajicDesigns. These work together to provide easy text display and animation capabilities.
Wire the matrix module: VCC to 5V, GND to GND, DIN to pin 11, CS to pin 10, CLK to pin 13. If using multiple 4-in-1 modules, connect DOUT of first module to DIN of second.
The library needs to know your module type. Most 4-in-1 modules use FC16_HW configuration. If text appears mirrored or upside down, try GENERIC_HW or PAROLA_HW instead.
Upload the code below to see scrolling text. Adjust MAX_DEVICES to match your number of 8x8 matrices (a 4-in-1 module = 4 devices).
Experiment with different scroll effects, speeds, and messages. The MD_Parola library offers effects like SCROLL_LEFT, SCROLL_RIGHT, FADE, WIPE, DISSOLVE, and many more.
Connect sensors (temperature, time from RTC) and display live data. Update the message string based on sensor readings or serial input.
// LED Matrix Scrolling Display // MakersDeck Arduino Project #include <MD_Parola.h> #include <MD_MAX72xx.h> #include <SPI.h> // Hardware configuration #define HARDWARE_TYPE MD_MAX72XX::FC16_HW #define MAX_DEVICES 4 // Number of 8x8 matrices // Pin definitions #define CLK_PIN 13 #define DATA_PIN 11 #define CS_PIN 10 // Create display object MD_Parola display = MD_Parola(HARDWARE_TYPE, CS_PIN, MAX_DEVICES); // Scroll settings uint8_t scrollSpeed = 50; // Lower = faster uint16_t scrollPause = 2000; // Pause at end (ms) textEffect_t scrollEffect = PA_SCROLL_LEFT; textPosition_t scrollAlign = PA_LEFT; // Messages to display const char *messages[] = { "Welcome to MakersDeck!", "Build Amazing Projects", "Learn Electronics", "Have Fun Making!" }; const int numMessages = 4; int currentMsg = 0; void setup() { Serial.begin(9600); // Initialize display display.begin(); display.setIntensity(5); // 0-15 brightness display.displayClear(); // Configure scroll effect display.displayText( messages[currentMsg], scrollAlign, scrollSpeed, scrollPause, scrollEffect, scrollEffect ); Serial.println("LED Matrix Ready!"); } void loop() { // Animate the display if (display.displayAnimate()) { // Animation complete, show next message currentMsg = (currentMsg + 1) % numMessages; display.displayText( messages[currentMsg], scrollAlign, scrollSpeed, scrollPause, scrollEffect, scrollEffect ); } // Check for serial input if (Serial.available()) { static char buffer[100]; static int idx = 0; char c = Serial.read(); if (c == '\n') { buffer[idx] = '\0'; display.displayText(buffer, scrollAlign, scrollSpeed, scrollPause, scrollEffect, scrollEffect); idx = 0; } else if (idx < 99) { buffer[idx++] = c; } } }
The MD_Parola library includes many stunning text effects: