#include <SoftwareSerial.h>

SoftwareSerial mySerial(1,0);
int buzzer = 8;
char dataIn;

void setup() {
  // put your setup code here, to run once:
mySerial.begin(9600);
pinMode(buzzer,OUTPUT);
}

void loop() {
  // put your main code here, to run repeatedly:
if(mySerial.available())
{
  dataIn = mySerial.read();
  if (dataIn == 'B')
  {
    digitalWrite(buzzer,HIGH);
  }
  else if (dataIn == 'W')
  {
    for(int i=0; i<3; i++)
    {
    digitalWrite(buzzer,HIGH);
    delay(200);
    digitalWrite(buzzer,LOW);
    delay(200);
    }
  }else{
    digitalWrite(buzzer,LOW);
  }
}
}