int soundPin = 2;


void setup() 
{
pinMode(soundPin, OUTPUT);
}

void loop() 
{
tone(soundPin, 300, 50);
delay(250);
tone(soundPin, 600, 50);
delay(250);
tone(soundPin, 900, 50);
delay(250);
tone(soundPin, 1200, 50);
delay(250);
}