int LED = 7; 
int TASTER = 8; 

// speichert den mit digitalRead gelesenen Wert
int TasterLesen; 

void setup()  
{ 
  pinMode(LED, OUTPUT);
  pinMode(TASTER, INPUT_PULLUP);
} 

void loop()  
{
  // Status des Tasters lesen (HIGH/LOW) 
  TasterLesen = digitalRead(TASTER);   
  if (TasterLesen == LOW)
  {
    delay(200);
    // Wert fuer LED schreiben
    // LOW = aus, HIGH = an
    digitalWrite(LED, HIGH); 
  }
}