DIY Vending Machine with Arduino

This is companion article for my YouTube video about how to make DIY Vending Machine using arduino and Coin Acceptor. This Vending machine works like real. It can sense a right coin. Only accept the coin defined and add the balance. Here’s the video

DIY Vending Machine with arduino Wiring Diagram

The Code

#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#include <SoftwareSerial.h>    //call library SoftwareSerial
#include <DFPlayer_Mini_Mp3.h> //call library DFPlayer mini

SoftwareSerial mp3(11, 10);
const int coin = 2;
boolean insert = false;
volatile int pulse = 0;

const int button1 = 3;
const int button2 = 4;
const int button3 = 5;

const int motor1A = 6;
const int motor1B = 7;
const int motor2A = 8;
const int motor2B = 9;
const int motor3A = 12;
const int motor3B = 13;

const int harga1 = 2000;
const int harga2 = 3000;
const int harga3 = 2000;

const int busyPin = 4;

unsigned long int saldo=0;

LiquidCrystal_I2C lcd(0x27, 16, 2);

void setup() {
  // put your setup code here, to run once:
  Serial.begin(9600);
  attachInterrupt(digitalPinToInterrupt(2), coinInterrupt, RISING);
  pinMode(motor1A, OUTPUT);
  pinMode(motor1B, OUTPUT);
  pinMode(motor2A, OUTPUT);
  pinMode(motor2B, OUTPUT);
  pinMode(motor3A, OUTPUT);
  pinMode(motor3B, OUTPUT);

  pinMode(button1, INPUT);
  pinMode(button2, INPUT);
  pinMode(button3, INPUT);
  digitalWrite(button1, HIGH);
  digitalWrite(button2, HIGH);
  digitalWrite(button3, HIGH);

  mp3.begin(9600);

  lcd.init();
  lcd.backlight();
  lcd.setCursor(0, 0);
  lcd.print("Vending Machine");
  lcd.setCursor(0, 1);
  lcd.print("");

  mp3_set_serial (mp3); //set softwareSerial for DFPlayer
  delay(10);

  mp3_reset();  //soft-Reset module DFPlayer

  delay(10);   //wait 1ms for respon command

  mp3_set_volume(15); //set Volume module DFPlayer
  delay(1000);
  lcd.clear();
}

void loop() {
  // put your main code here, to run repeatedly:
  if (insert) {
    insert = false;
    Serial.println("koin masuk");
    saldo += 1000;
    mp3_play (1);
    delay(1000);
  }
  lcd.setCursor(0, 0);
  lcd.print("Balance : " + (String)saldo+"        ");
  if (saldo > 0) {
    lcd.setCursor(0, 1);
    lcd.print("Press button");
  }

  if (digitalRead(button1) == LOW) {
    if (saldo >= harga1) {
      saldo -= harga1;
      ambil1();
      delay(3000);
      stopMotor1();
    } else {
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("Sorry not enough");
      lcd.setCursor(0, 1);
      lcd.print("balance");
      mp3_play (2);
      delay(2000);
    }
  }
  if (digitalRead(button2) == LOW) {
    if (saldo >= harga2) {
      saldo -= harga2;
      ambil2();
      delay(3000);
      stopMotor2();
    } else {
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("Sorry not enough");
      lcd.setCursor(0, 1);
      lcd.print("balance");
      mp3_play (2);
      delay(2000);
    }
  }
  if (digitalRead(button3) == LOW) {
    if (saldo >= harga3) {
      saldo -= harga3;
      ambil3();
      delay(3000);
      stopMotor3();
    } else {
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("Sorry not enough");
      lcd.setCursor(0, 1);
      lcd.print("balance");
      mp3_play (2);
      delay(2000);
    }
  }
}

//interrupt
void coinInterrupt() {
  pulse++ ;
  insert = true;
}

void ambil1() {
  digitalWrite(motor1A, HIGH);
  digitalWrite(motor1B, LOW);
}

void stopMotor1() {
  digitalWrite(motor1A, LOW);
  digitalWrite(motor1B, LOW);
}

void ambil2() {
  digitalWrite(motor2A, HIGH);
  digitalWrite(motor2B, LOW);
}

void stopMotor2() {
  digitalWrite(motor2A, LOW);
  digitalWrite(motor2B, LOW);
}

void ambil3() {
  digitalWrite(motor3A, HIGH);
  digitalWrite(motor3B, LOW);
}

void stopMotor3() {
  digitalWrite(motor3A, LOW);
  digitalWrite(motor3B, LOW);
}