const byte taste = 6;
const byte beeper = 8;
const byte maxZaehler = 3;
byte zaehler = 0;
byte lastZaehler = 0;
void setup()
{
  Serial.begin(115200);
  Serial.println(F("Start..."));
  pinMode(taste, INPUT_PULLUP);
}

void loop()
{
  if (!digitalRead(taste)) zaehler++;
  if (zaehler > maxZaehler) zaehler = 1;
  if (zaehler != lastZaehler)
  {
    Serial.println("beep");
    tone(beeper,4000-zaehler*1000,100);
    delay(200);
    lastZaehler = zaehler;
 }
}