void init_port(void);
void init_timer();

void setup() {
  // put your setup code here, to run once:
  volatile long i;
  int j=0;
  init_port();
  init_timer();
   Serial.begin(9600);
  while(1)
  {
      for(i=0;i<100000;i++);
      Serial.println(j,DEC);
      j++;
  }
}

void init_timer()
{
  volatile char  *Timer_TCCR1A = 0x80;
  volatile char  *Timer_TCCR1B = 0x81;
  volatile short *Timer_TCNT1  = 0x84;
  volatile short *Timer_OCR1A  = 0x88;
  volatile char  *Timer_T1MSK1 = 0x6f;

  *Timer_TCCR1A = 0;
  *Timer_TCCR1B = 0;
  *Timer_TCNT1  = 0;

  *Timer_OCR1A  = 60000;
  *Timer_TCCR1B = 0x0c;
  *Timer_T1MSK1 = 0x02;

}

void init_port()
{
    volatile char *portf_dir =(volatile char *) 0x30;
    *portf_dir = 0x01;

}

ISR(TIMER1_COMPA_vect)
{
  volatile char *portf_data =(volatile char *) 0x31;
  *portf_data ^= 0x01;

}

void loop() {
  // put your main code here, to run repeatedly:

}