#include "avr/io.h"
  int main ( )
  {
    unsigned int t;
    ddra = 0xff;  
    ddrb = 0xff;  
    portd = 0xff;  
    tccr1a = 0;  
    tccr1b = 0x41; 
    while ((tifr&(1<<icf1)) == 0);
    t = icr1;
    tifr = (1<<icf1);  
    while ((tifr&(1<<icf1)) == 0);
    t = icr1 - t;
    porta = t;    
    portb = t>>8;  
    while (1);
    return 0;
  }