int ledPin = 8;
int tipka = 2;


volatile byte stanje = LOW;
void setup() {
  // put your setup code here, to run once:
  
  pinMode(ledPin, OUTPUT);
  pinMode(tipka, INPUT_PULLUP);
  attachInterrupt(digitalPinToInterrupt(tipka), ISR_tipka, FALLING);
}

void loop() {
  digitalWrite(ledPin,stanje);
  //delay(500);

}
void ISR_tipka(){
  stanje = !stanje;
}