char  C;
void setup()
{
  Serial.begin(115200);
  pinMode (13,OUTPUT);

}
void loop()
{
  int n = Serial.available();
  if (n>0)
  {
    C = Serial.read();
    if (C == ' 0 ')
    {
      digitalWrite(13,0); // LED off
    }
    if ( C == ' 1 ')
    {
      digitalWrite (13,1);  //LED On
    }
  }

  if ( C == ' 2 ')
 {
      digitalWrite (13,1);  
      delay(200);
      digitalWrite(13,0);
      delay(200);
  }  
  if(C == '3')
  {
    digitalWrite(13,1);
    delay(3);
    digitalWrite(13,0);
    delay(20);
  }
}