unsigned char Bluetooth_val;       //defining variable val
#define Lpwm_pin  9 //enB
#define Rpwm_pin  10 //enA
int pinLF = 4; //in1
int pinLB = 5; //in2
int pinRF = 6; //in3
int pinRB = 7; //in4

unsigned char Lpwm_val = 150;
unsigned char Rpwm_val = 150;

int Car_state = 0;

void M_Control_IO_config(void)
{
  pinMode(pinLB, OUTPUT);
  pinMode(pinLF, OUTPUT);
  pinMode(pinRB, OUTPUT);
  pinMode(pinRF, OUTPUT);
  pinMode(Lpwm_pin, OUTPUT); // pin 10 (PWM)
  pinMode(Rpwm_pin, OUTPUT); // pin 9 (PWM)
}
void Set_Speed(unsigned char Left, unsigned char Right)
{
  analogWrite(Lpwm_pin, Left);
  analogWrite(Rpwm_pin, Right);
}
void turnR()     //  going forward
{
  digitalWrite(pinRB, LOW); // making motor move towards right rear
  digitalWrite(pinRF, HIGH);
  digitalWrite(pinLB, LOW); // making motor move towards left rear
  digitalWrite(pinLF, HIGH);
  Car_state = 1;
}
void back()        //turning right(dual wheel)
{
  digitalWrite(pinRB, LOW); //making motor move towards right rear
  digitalWrite(pinRF, HIGH);
  digitalWrite(pinLB, HIGH);
  digitalWrite(pinLF, LOW); //making motor move towards left front
  Car_state = 4;
}
void advance()        //turning left(dual wheel)
{
  digitalWrite(pinRB, HIGH);
  digitalWrite(pinRF, LOW );  //making motor move towards right front
  digitalWrite(pinLB, LOW);  //making motor move towards left rear
  digitalWrite(pinLF, HIGH);
  Car_state = 3;
}
void stopp()         //stop
{
  digitalWrite(pinRB, HIGH);
  digitalWrite(pinRF, HIGH);
  digitalWrite(pinLB, HIGH);
  digitalWrite(pinLF, HIGH);
  Car_state = 5;
}
void turnL()          //back up
{
  digitalWrite(pinRB, HIGH); //making motor move towards right rear
  digitalWrite(pinRF, LOW);
  digitalWrite(pinLB, HIGH); //making motor move towards left rear
  digitalWrite(pinLF, LOW);
  Car_state = 2;
}

void forwardLeft() {
  advance();
  delay(50);
  turnL();
  delay(100);
  advance();
  delay(50);
} //G
void forwardRight() {
  advance();
  delay(50);
  turnR();
  delay(100);
  advance();
  delay(50);
} //I
void backLeft() {
  back();
  delay(50);
  turnR();
  delay(100);
  back();
  delay(50);
} //H
void backRight() {
  back();
  delay(50);
  turnL();
  delay(100);
  back();
  delay(50);
} //J

void hornON(){digitalWrite(13,1);}
void hornOFF(){digitalWrite(13,0);}
void setup()
{
  pinMode(13,OUTPUT);
  M_Control_IO_config();
  Set_Speed(Lpwm_val, Rpwm_val);
  Serial.begin(9600);   //initialized serial port , using Bluetooth as serial port, setting baud at 9600
  stopp();
}

void loop()
{
  if (Serial.available()) //to judge whether the serial port receives the data.
  {
    Bluetooth_val = Serial.read(); //reading (Bluetooth) data of serial port,giving the value of val;
    switch (Bluetooth_val)
    {
      case 'F': advance(); //UP
        break;
      case 'B': back();   //back
        break;
      case 'L': turnL();  //Left
        break;
      case 'R': turnR(); //Right
        break;
      case 'S': stopp();   //stop
        break;
      case 'G': stopp();
        break;
      case 'I': stopp();
        break;
      case 'H': stopp();
        break;
      case 'J': stopp();
        break;
      case 'W': stopp();
        break;
      case 'w': stopp();
        break;
      case 'U': stopp();
        break;
      case 'u': stopp();
        break;
      case 'V': hornON();
        break;
      case 'v': hornOFF();
        break;
      case 'X': stopp();
        break;
      case 'x': stopp();
        break;
      case 'D': stopp();
        break;
    }
  }
}