Programming

// Bluetooth-Controlled Robot Car
// Arduino UNO + HC-05 + L298N

// L298N Motor Driver Pins
int ENA = 5;   // Left motor speed
int IN1 = 8;
int IN2 = 9;

int ENB = 6;   // Right motor speed
int IN3 = 10;
int IN4 = 11;

// HC-05 Bluetooth
// HC-05 TX -> Arduino pin 2
// HC-05 RX -> Arduino pin 3
#include <SoftwareSerial.h>

SoftwareSerial Bluetooth(2, 3); // RX, TX

int motorSpeed = 200;

void setup() {
  pinMode(ENA, OUTPUT);
  pinMode(IN1, OUTPUT);
  pinMode(IN2, OUTPUT);

  pinMode(ENB, OUTPUT);
  pinMode(IN3, OUTPUT);
  pinMode(IN4, OUTPUT);

  Bluetooth.begin(9600);
  Serial.begin(9600);

  stopCar();
}

void loop() {

  if (Bluetooth.available()) {

    char command = Bluetooth.read();

    Serial.println(command);

    switch (command) {

      case 'F':
        forward();
        break;

      case 'B':
        backward();
        break;

      case 'L':
        left();
        break;

      case 'R':
        right();
        break;

      case 'S':
        stopCar();
        break;
    }
  }
}

// Move Forward
void forward() {
  analogWrite(ENA, motorSpeed);
  analogWrite(ENB, motorSpeed);

  digitalWrite(IN1, HIGH);
  digitalWrite(IN2, LOW);

  digitalWrite(IN3, HIGH);
  digitalWrite(IN4, LOW);
}

// Move Backward
void backward() {
  analogWrite(ENA, motorSpeed);
  analogWrite(ENB, motorSpeed);

  digitalWrite(IN1, LOW);
  digitalWrite(IN2, HIGH);

  digitalWrite(IN3, LOW);
  digitalWrite(IN4, HIGH);
}

// Turn Left
void left() {
  analogWrite(ENA, motorSpeed);
  analogWrite(ENB, motorSpeed);

  digitalWrite(IN1, LOW);
  digitalWrite(IN2, HIGH);

  digitalWrite(IN3, HIGH);
  digitalWrite(IN4, LOW);
}

// Turn Right
void right() {
  analogWrite(ENA, motorSpeed);
  analogWrite(ENB, motorSpeed);

  digitalWrite(IN1, HIGH);
  digitalWrite(IN2, LOW);

  digitalWrite(IN3, LOW);
  digitalWrite(IN4, HIGH);
}

// Stop Robot
void stopCar() {
  analogWrite(ENA, 0);
  analogWrite(ENB, 0);

  digitalWrite(IN1, LOW);
  digitalWrite(IN2, LOW);

  digitalWrite(IN3, LOW);
  digitalWrite(IN4, LOW);
}