4WD Car Robot BT (HC-05)

unsigned char Bluetooth_val;       //defining variable val

#define Lpwm_pin  5     //adjusting speed
#define Rpwm_pin  10    //adjusting speed

int pinLB=2;     // defining pin2 left rear
int pinLF=4;     // defining pin4 left front
int pinRB=7;    // defining pin7 right rear
int pinRF=8;    // defining pin8 right front

unsigned char Lpwm_val = 255;
unsigned char Rpwm_val = 255;

int Car_state=0;

void M_Control_IO_config(void)
{
  pinMode(pinLB,OUTPUT); // pin 2
  pinMode(pinLF,OUTPUT); // pin 4
  pinMode(pinRB,OUTPUT); // pin 7
  pinMode(pinRF,OUTPUT); // pin 8
  pinMode(Lpwm_pin,OUTPUT); // pin 11 (PWM)
  pinMode(Rpwm_pin,OUTPUT); // pin 10 (PWM)
}
void Set_Speed(unsigned char Left,unsigned char Right)
{
  analogWrite(Lpwm_pin,Left);
  analogWrite(Rpwm_pin,Right);
}

void advance()     //  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 turnR()        //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 turnL()        //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 back()          //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 setup()
{
   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 'U':advance(); //UP
       break;
       case 'D': back();   //back
       break;
       case 'L':turnL();   //Left
       break;
       case 'R':turnR();  //Right
       break;
       case 'S':stopp();    //stop
       break;
     }
    }
}