LED Matrix

Hardware Setup:

• LED Matrix: 8x8 LED matrix with MAX7219 controller (the common 16-pin module)
• Connections:
  • VCC → 5V
  • GND → GND
  • DIN → Pin 11
  • CS → Pin 10
  • CLK → Pin 13
• Potentiometers: Connect middle pins to A0 and A1, outer pins to GND and 5V

Features:

1. Multiple Display Modes: Potentiometer 1 switches between 5 different patterns
2. Brightness Control: Potentiometer 2 controls the LED brightness
3. Interactive Patterns:
   • Moving dot controlled by both potentiometers
   • Smiley face pattern
   • Heart pattern
   • Arrow pattern
   • Spinning line animation

Required Library:

You'll need to install the LedControl library:

1. Go to Arduino IDE → Tools → Manage Libraries
2. Search for "LedControl" by Eberhard Fahle
3. Install it

How It Works:

• Turn potentiometer 1 to cycle through different display patterns
• Turn potentiometer 2 to adjust brightness or control the Y-position (depending on mode)
• The serial monitor shows real-time values for debugging

The code is well-commented and includes additional functions you can explore, like a test mode for all LEDs and a foundation for scrolling text. You can easily modify the patterns or add your own custom designs by creating new byte arrays!

/*
  LED Matrix Display with Arduino Uno and 2 Potentiometers
  
  Hardware Required:
  - Arduino Uno
  - 8x8 LED Matrix with MAX7219 controller (16-pin)
  - 2 Potentiometers (10kΩ recommended)
  - Jumper wires
  - Breadboard
  
  Connections:
  LED Matrix (MAX7219):
  - VCC -> 5V
  - GND -> GND
  - DIN -> Pin 11 (MOSI)
  - CS  -> Pin 10
  - CLK -> Pin 13 (SCK)
  
  Potentiometers:
  - Pot 1: Left pin to GND, Middle pin to A0, Right pin to 5V
  - Pot 2: Left pin to GND, Middle pin to A1, Right pin to 5V
*/

#include <LedControl.h>

// Initialize the LED matrix
// Pin 11 is connected to the DataIn (DIN)
// Pin 13 is connected to the CLK (Clock)
// Pin 10 is connected to CS (Chip Select)
// We have only 1 MAX7219
LedControl lc = LedControl(11, 13, 10, 1);

// Potentiometer pins
const int pot1Pin = A0;  // Controls X position or pattern
const int pot2Pin = A1;  // Controls Y position or brightness

// Variables
int pot1Value = 0;
int pot2Value = 0;
int ledX = 0;
int ledY = 0;
int brightness = 8;

// Pattern arrays for different displays
byte smiley[8] = {
  B00111100,
  B01000010,
  B10100101,
  B10000001,
  B10100101,
  B10011001,
  B01000010,
  B00111100
};

byte heart[8] = {
  B00000000,
  B01100110,
  B11111111,
  B11111111,
  B01111110,
  B00111100,
  B00011000,
  B00000000
};

byte arrow[8] = {
  B00001000,
  B00001100,
  B00001110,
  B11111111,
  B11111111,
  B00001110,
  B00001100,
  B00001000
};

void setup() {
  Serial.begin(9600);
  
  // Initialize the MAX7219 device
  lc.shutdown(0, false);       // Wake up displays
  lc.setIntensity(0, 8);       // Set brightness level (0 is min, 15 is max)
  lc.clearDisplay(0);          // Clear display register
  
  Serial.println("LED Matrix with Potentiometers Ready!");
  Serial.println("Pot 1 (A0): Controls pattern/X position");
  Serial.println("Pot 2 (A1): Controls brightness/Y position");
}

void loop() {
  // Read potentiometer values
  pot1Value = analogRead(pot1Pin);
  pot2Value = analogRead(pot2Pin);
  
  // Map potentiometer values to useful ranges
  int pattern = map(pot1Value, 0, 1023, 0, 4);  // 5 different patterns/modes
  brightness = map(pot2Value, 0, 1023, 0, 15);  // Brightness from 0 to 15
  
  // Set brightness based on pot2
  lc.setIntensity(0, brightness);
  
  // Clear the display
  lc.clearDisplay(0);
  
  // Display different patterns based on pot1 value
  switch(pattern) {
    case 0:
      // Single moving dot
      ledX = map(pot1Value, 0, 1023, 0, 7);
      ledY = map(pot2Value, 0, 1023, 0, 7);
      lc.setLed(0, ledY, ledX, true);
      break;
      
    case 1:
      // Display smiley face
      displayPattern(smiley);
      break;
      
    case 2:
      // Display heart
      displayPattern(heart);
      break;
      
    case 3:
      // Display arrow
      displayPattern(arrow);
      break;
      
    case 4:
      // Custom animation - spinning line
      displaySpinningLine();
      break;
  }
  
  // Print values to serial monitor for debugging
  Serial.print("Pot1: ");
  Serial.print(pot1Value);
  Serial.print(" | Pot2: ");
  Serial.print(pot2Value);
  Serial.print(" | Pattern: ");
  Serial.print(pattern);
  Serial.print(" | Brightness: ");
  Serial.println(brightness);
  
  delay(100);  // Small delay for stability
}

// Function to display a pattern from an array
void displayPattern(byte pattern[8]) {
  for (int i = 0; i < 8; i++) {
    lc.setRow(0, i, pattern[i]);
  }
}

// Function to display a spinning line animation
void displaySpinningLine() {
  static int linePosition = 0;
  static unsigned long lastUpdate = 0;
  
  // Update animation every 200ms
  if (millis() - lastUpdate > 200) {
    lc.clearDisplay(0);
    
    // Draw line based on position
    switch(linePosition) {
      case 0: // Horizontal line
        for (int i = 0; i < 8; i++) {
          lc.setLed(0, 3, i, true);
        }
        break;
      case 1: // Diagonal line /
        for (int i = 0; i < 8; i++) {
          lc.setLed(0, 7-i, i, true);
        }
        break;
      case 2: // Vertical line
        for (int i = 0; i < 8; i++) {
          lc.setLed(0, i, 3, true);
        }
        break;
      case 3: // Diagonal line \
        for (int i = 0; i < 8; i++) {
          lc.setLed(0, i, i, true);
        }
        break;
    }
    
    linePosition = (linePosition + 1) % 4;
    lastUpdate = millis();
  }
}

// Additional function: Test all LEDs
void testAllLEDs() {
  // Turn on all LEDs
  for (int row = 0; row < 8; row++) {
    for (int col = 0; col < 8; col++) {
      lc.setLed(0, row, col, true);
      delay(50);
    }
  }
  delay(1000);
  
  // Turn off all LEDs
  for (int row = 0; row < 8; row++) {
    for (int col = 0; col < 8; col++) {
      lc.setLed(0, row, col, false);
      delay(50);
    }
  }
}

// Function to create scrolling text effect (bonus feature)
void scrollText(String text) {
  // This is a simplified version - you can expand it
  // to create actual scrolling text patterns
  for (int i = 0; i < text.length(); i++) {
    lc.clearDisplay(0);
    // You would need to define character patterns here
    delay(500);
  }
}