unsigned long int future = 0; // cislo 0 az 2na32
int stav = 0;
void setup()
{
 DDRD |=1<<5;   //pinMode(5, OUTPUT);
 DDRD |=1<<6;   //pinMode(6, OUTPUT);
 DDRD |=1<<7;   //pinMode(7, OUTPUT);
 PORTD &=~(1<<5);
 PORTD &=~(1<<6);
 PORTD &=~(1<<7);
 future = millis(); // urcenie zaciatocneho casu po inicializacii systemu
}
void loop()
{
 if(millis() >= future) // pokial aktualny cas dosiahol stanoveny interval...
 {
 stav++; // kod, ktory sa vykona raz za pol sekundy
 if(stav == 3)
 stav = 0;
 future = millis() + 200; // stanovenie noveho intervalu
 }


 switch(stav) // stavovy stoj
 {
 case 0: (PORTD |=1<<5); (PORTD &=~(1<<5)); break; 
 //digitalWrite(5, HIGH); digitalWrite(5, LOW); break;
 case 1: (PORTD |=1<<6); (PORTD &=~(1<<6)); break; 
 //digitalWrite(6, HIGH); digitalWrite(6, LOW); break;
 case 2: (PORTD |=1<<7); (PORTD &=~(1<<7)); break; 
 //digitalWrite(7, HIGH); digitalWrite(7, LOW); break;
 default: break; // toto nenastane "SNÁĎ!!!"
 }
 
}