//Arduino timer CTC interrupt example
//
//avr-libc library includes
//#include <arduino.h>
//#include <avr/io.h>
//include <avr/interrupt.h>
#include <TimerOne.h>
#define LEDPIN 13
#define LEDPIN2 12
#define LEDPIN3 11

void setup()
{
  Serial.begin(9600);
  pinMode(LEDPIN, OUTPUT);
  pinMode(LEDPIN2, OUTPUT);
  pinMode(LEDPIN3, OUTPUT);
  //initialize Timer1
  Timer1.initialize(100); //us
  Timer1.attachInterrupt(timerISR);
 }

void loop()
{
  Serial.print("LED 1 is :" );
  if(digitalRead(LEDPIN)==HIGH) {
	  Serial.println("On");
  }
  else {
	  Serial.println("Off");
  }
  Serial.print("LED 2 is :" );
    if(digitalRead(LEDPIN2)==HIGH) {
  	  Serial.println("On");
    }
    else {
  	  Serial.println("Off");
    }
    Serial.print("LED 3 is :" );
      if(digitalRead(LEDPIN3)==HIGH) {
    	  Serial.println("On");
      }
      else {
    	  Serial.println("Off");
      }
  
  
  delay(1);
}

void timerISR(void)
{
  static int tick=0;
  if(tick % 2 == 1){  //ungerade zahlen 1,3,5,7,9
  digitalWrite(LEDPIN, !digitalRead(LEDPIN));
  }
  else if(tick % 4 == 2){ //2,6,10,
  digitalWrite(LEDPIN2,!digitalRead(LEDPIN2));
  }
  else if(tick % 8 == 4){ //4,12,20,
  digitalWrite(LEDPIN3,!digitalRead(LEDPIN3));
   	}
  
  tick++;
}