#define pin
#define mode
const  int outputPin = 10;

void setup()
{
  pin mode(outputPin, OUTPUT);
  Serial.begin(9600)
  Serial.println("Podaj czestotliwosc od 100 do 800 Hz");
  
}

void loop
{
  if (Serial.available())
  {
    int f = Serial.parseInt();
    if (f == 0){
     noTone(outputPin);
   }
   else {  
     tone(outputPin, f);   
   }
  }
}