Bluetooth Controlled Robot

char temp;
void setup()
{
  // put your setup code here, to run once:
  // confgure port pins as o/p
  //pins 11, 12, 13 and 14 are used for L293D motor driver
  pinMode(11,OUTPUT);
  pinMode(12,OUTPUT);
  pinMode(13,OUTPUT);
  pinMode(14,OUTPUT);
  // initial state of all the pins is LOW
  digitalWrite(11,LOW);
  digitalWrite(12,LOW);
  digitalWrite(13,LOW);
  digitalWrite(14,LOW);
  // initialize Serial communication
  Serial.begin(9600);
}

void loop() {
  // put your main code here, to run repeatedly: 

  while(!Serial.available()); // wait for serial data
  if(Serial.available()>0) // execute when serial data is received
  {
    temp=Serial.read(); // read the serial data byte and store in temp variable
    if(temp=='A') // check if received data is 'A'
    {
      // move forward
      digitalWrite(11,HIGH);
      digitalWrite(12,LOW);
      digitalWrite(13,LOW);
      digitalWrite(14,HIGH);
    }
    if(temp=='B')
    {
      //move backward
      digitalWrite(11,LOW);
      digitalWrite(12,HIGH);
      digitalWrite(13,HIGH);
      digitalWrite(14,LOW);

    }

    if(temp=='C')
    {
      
      //move left
      digitalWrite(11,HIGH);
      digitalWrite(12,LOW);
      digitalWrite(13,LOW);
      digitalWrite(14,LOW);

    }
    
    if(temp=='D')
    {
      //move right
      digitalWrite(11,LOW);
      digitalWrite(12,LOW);
      digitalWrite(13,LOW);
      digitalWrite(14,HIGH);
      
    }
    
    if(temp=='E')
    {
      //stop robot
      digitalWrite(11,LOW);
      digitalWrite(12,LOW);
      digitalWrite(13,LOW);
      digitalWrite(14,LOW);
    }
  }
}