Arduino Project

Arduino Slot Machine Project V3

Kit purchase

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Name	Includes Arduino board	PURCHASE LINK
Elite Explorer Kit	Arduino Uno R4 WiFi	BUY
3 in 1 Ultimate Starter Kit	Arduino Uno R3	BUY

Course Introduction

In this lesson, you’ll learn how to use an I2C LCD, a button, and a buzzer with the Arduino R4 UNO WIFI to create a Slot Machine game 3.0.

The I2C LCD shows spinning reels with custom icons, the button starts the spin, and the buzzer plays sound effects for spinning, winning, or losing.

Note

If this is your first time working with an Arduino project, we recommend downloading and reviewing the basic materials first.

1.1 Install Arduino IDE(Important)
1.2 Introduction of Arduino IDE

Required Components

In this project, we need the following components:

SN	COMPONENT INTRODUCTION	QUANTITY	PURCHASE LINK
1	Arduino UNO R4 Wifi	1	BUY
2	USB Type-C cable	1	×
3	Breadboard	1	BUY
4	Wires	Several	BUY
5	I2C LCD 1602	1	BUY
6	Button	1	BUY
7	Active Buzzer	1	×

Wiring

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Common Connections:

I2C LCD 1602
SDA: Connect to SDA on the Arduino.
SCK: Connect to SCL on the Arduino.
GND: Connect to breadboard’s negative power bus.
VCC: Connect to breadboard’s red power bus.

Button
Connect to breadboard’s negative power bus.
Connect to 2 on the Arduino.

Active Buzzer
Connect to breadboard’s negative power bus.
Connect to 9 on the Arduino.

Writing the Code

Note
You can copy this code into Arduino IDE.
To install the library, use the Arduino Library Manager and search for LiquidCrystal_I2C.h and install it.
Don’t forget to select the board(Arduino UNO R4 WIFI) and the correct port before clicking the Upload button.

#include <Wire.h>
#include <LiquidCrystal_I2C.h>

// ==============================
// LCD
// ==============================
LiquidCrystal_I2C lcd(0x27, 16, 2);

// ==============================
// Pins
// ==============================
#define BTN_PIN     2
#define BUZZER_PIN  9

// ==============================
// Slot symbols
// ==============================
enum Symbol {
  CHERRY = 0,
  STAR,
  LEMON,
  HEART,
  SEVEN
};

const int ICON_COUNT = 5;

int reels[3] = {
  CHERRY,
  STAR,
  LEMON
};

// ==============================
// LCD custom characters
// ==============================

// Cherry
byte cherryChar[8] = {
  B00100,
  B00110,
  B00101,
  B01010,
  B10101,
  B10101,
  B01010,
  B00000
};

// Star
byte starChar[8] = {
  B00100,
  B10101,
  B01110,
  B11111,
  B01110,
  B10101,
  B00100,
  B00000
};

// Lemon
byte lemonChar[8] = {
  B00000,
  B00110,
  B01111,
  B11111,
  B11111,
  B11110,
  B01100,
  B00000
};

// Heart
byte heartChar[8] = {
  B00000,
  B01010,
  B11111,
  B11111,
  B11111,
  B01110,
  B00100,
  B00000
};

// Seven
byte sevenChar[8] = {
  B11111,
  B00001,
  B00010,
  B00100,
  B01000,
  B01000,
  B01000,
  B00000
};

// ==============================
// Sound effects
// ==============================

void playWinJingle() {
  int notes[] = {
    784,
    988,
    1175,
    1568
  };

  int durations[] = {
    120,
    120,
    120,
    220
  };

  for (int i = 0; i < 4; i++) {
    tone(
      BUZZER_PIN,
      notes[i],
      durations[i]
    );

    delay(durations[i] + 40);
  }

  noTone(BUZZER_PIN);
}

// Lose sound
void playLoseBeep() {
  tone(BUZZER_PIN, 420, 100);
  delay(130);

  tone(BUZZER_PIN, 360, 100);
  delay(130);

  noTone(BUZZER_PIN);
}

// Start sound
void playStartChirp() {
  tone(BUZZER_PIN, 900, 80);
  delay(90);

  tone(BUZZER_PIN, 1200, 90);
  delay(110);

  noTone(BUZZER_PIN);
}

// Spin tick
void spinTick() {
  tone(BUZZER_PIN, 950, 18);
}

// ==============================
// LCD symbol drawing
// ==============================

void printSymbol(int symbol) {
  switch (symbol) {

    case CHERRY:
      lcd.write(byte(0));
      break;

    case STAR:
      lcd.write(byte(1));
      break;

    case LEMON:
      lcd.write(byte(2));
      break;

    case HEART:
      lcd.write(byte(3));
      break;

    case SEVEN:
      lcd.write(byte(4));
      break;
  }
}

// ==============================
// Display three reels
// ==============================

void showReels() {

  lcd.setCursor(1, 1);

  lcd.print("[");

  printSymbol(reels[0]);

  lcd.print("] ");

  lcd.print("[");

  printSymbol(reels[1]);

  lcd.print("] ");

  lcd.print("[");

  printSymbol(reels[2]);

  lcd.print("]");
}

// ==============================
// Jackpot detection
// ==============================

bool isJackpot() {

  return (
    reels[0] == reels[1] &&
    reels[1] == reels[2]
  );
}

// ==============================
// Idle screen
// ==============================

void showIdle() {

  lcd.clear();

  lcd.setCursor(0, 0);
  lcd.print("SLOT - PRESS BTN");

  showReels();
}

// ==============================
// Spinning screen
// ==============================

void drawSpinScreen() {

  lcd.setCursor(0, 0);
  lcd.print("   SPINNING...  ");

  showReels();
}

// ==============================
// Spin
// ==============================

void spinAndStop() {

  playStartChirp();

  unsigned long startTime =
    millis();

  unsigned long stopAt[3] = {
    startTime + 700,
    startTime + 1100,
    startTime + 1500
  };

  int stepDelay[3] = {
    80,
    110,
    140
  };

  bool stopped[3] = {
    false,
    false,
    false
  };

  unsigned long lastStep[3] = {
    0,
    0,
    0
  };

  unsigned long lastTick = 0;

  while (
    !(stopped[0] &&
      stopped[1] &&
      stopped[2])
  ) {

    unsigned long now =
      millis();

    bool changed = false;

    for (int r = 0; r < 3; r++) {

      if (!stopped[r]) {

        if (now >= stopAt[r]) {

          stopped[r] = true;

          reels[r] =
            random(ICON_COUNT);

          changed = true;

        } else {

          if (
            now - lastStep[r] >=
            (unsigned long)stepDelay[r]
          ) {

            lastStep[r] = now;

            reels[r] =
              (reels[r] + 1) %
              ICON_COUNT;

            changed = true;
          }
        }
      }
    }

    if (
      changed &&
      now - lastTick >= 50
    ) {

      spinTick();

      lastTick = now;
    }

    drawSpinScreen();

    delay(10);
  }
}

// ==============================
// Result screen
// ==============================

void showResult() {

  lcd.clear();

  if (isJackpot()) {

    lcd.setCursor(1, 0);
    lcd.print("JACKPOT! WIN!");

    showReels();

    playWinJingle();

  } else {

    lcd.setCursor(3, 0);
    lcd.print("TRY AGAIN");

    showReels();

    playLoseBeep();
  }

  delay(2000);
}

// ==============================
// Setup
// ==============================

void setup() {

  pinMode(
    BTN_PIN,
    INPUT_PULLUP
  );

  pinMode(
    BUZZER_PIN,
    OUTPUT
  );

  noTone(BUZZER_PIN);

  // Start I2C
  Wire.begin();

  // Initialize LCD
  lcd.init();

  // Turn on backlight
  lcd.backlight();

  // Create custom symbols
  lcd.createChar(
    0,
    cherryChar
  );

  lcd.createChar(
    1,
    starChar
  );

  lcd.createChar(
    2,
    lemonChar
  );

  lcd.createChar(
    3,
    heartChar
  );

  lcd.createChar(
    4,
    sevenChar
  );

  // Random seed
  randomSeed(
    analogRead(A0)
  );

  showIdle();
}

// ==============================
// Main loop
// ==============================

void loop() {

  if (
    digitalRead(BTN_PIN) ==
    LOW
  ) {

    delay(25);

    if (
      digitalRead(BTN_PIN) ==
      LOW
    ) {

      spinAndStop();

      showResult();

      while (
        digitalRead(BTN_PIN) ==
        LOW
      ) {
        delay(10);
      }

      delay(150);

      showIdle();
    }
  }
}

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Arduino Project

Arduino Slot Machine Project V3

Kit purchase

Course Introduction

Required Components

Wiring

Common Connections:

Writing the Code

Arduino Project

Arduino Slot Machine Project V3

Kit purchase

Course Introduction

Required Components

Wiring

Common Connections:

Writing the Code

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