BT_Round_CAR_1_2_3_4_5

#define INT_A 2    // control the left motor direction pin D2
#define INT_B 4    // control the right motor direction pin D4
#define left_A 9    // define the left motor speed control pin as D9
#define right_B 5   // define the right motor speed control pin as D5

String str;
int blueToothVal;


void setup()
{
  Serial.begin(9600);
  pinMode(INT_A, OUTPUT);          // set the motor control pin as OUTPUT
  pinMode(INT_B, OUTPUT);
  pinMode(left_A, OUTPUT);
  pinMode(right_B, OUTPUT);
}


void loop() {

  bluetooth();
}//end of loop

void bluetooth()
{
  while (Serial.available()){
    {
      str = Serial.readStringUntil('\n');               // str is the temporary variable for storing the last sring sent over bluetooth from Android device
      //Serial.print(str);
    }

    blueToothVal = (str.toInt());                        //  convert the string 'str' into an integer and assign it to blueToothVal

    switch (blueToothVal)
    {
      case 1:
        FRONT();
        delay(10);
        break;

      case 2:
        BACKWARDS();
        delay(10);
        break;

      case 3:
        LEFTT();
        delay(10);
        //STOP();
        break;

      case 4:
        RIGHTT();
        delay(10);
        //STOP();
        break;

      case 5:
        STOP();
        break;

    }                                                              // end of switch case

  }                                                              // end of while loop Serial1 read


}
// go forward
void FRONT()
{
  digitalWrite(INT_A, LOW);   // control the left motor turn forward
  digitalWrite(INT_B, LOW);  // control the right motor turn forward
  analogWrite(left_A, 200);  // set the two motors’ speed（PWM=200)
  analogWrite(right_B, 200);
}
// backward
void BACKWARDS()
{
  digitalWrite(INT_A, HIGH);  // control the left motor turn backward
  digitalWrite(INT_B, HIGH);   // control the right motor turn backward
  analogWrite(left_A, 200);  // set the two motors’ speed （PWM=200)
  analogWrite(right_B, 200);
}
// turn left
void LEFTT()
{
  digitalWrite(INT_A, HIGH);   // control the left motor turn backward
  digitalWrite(INT_B, LOW);   // control the right motor turn forward
  analogWrite(left_A, 100);   // set the two motors’ speed（PWM为100）
  analogWrite(right_B, 100);
}
// turn right
void RIGHTT()
{
  digitalWrite(INT_A, LOW);    // control the left motor turn forward
  digitalWrite(INT_B, HIGH);    // control the right motor turn backward
  analogWrite(left_A, 100);   // two motors’ speed（PWM为100）
  analogWrite(right_B, 100);
}
// stop
void STOP()
{
  digitalWrite(INT_A, LOW);
  digitalWrite(INT_B, LOW);
  analogWrite(left_A, 0);   // both PWM are 0
  analogWrite(right_B, 0);
}