.include "m32def.inc"
    ldi  r16,0xff
    out  ddrb,r16  
    out  portd,r16
  begin:ldi  r20,0x00
    out  tccr1a,r20  
    ldi  r20,0x45
    out  tccr1b,r20  
  l1:  in  r21,tifr
    sbrs  r21,icf1  
    rjmp  l1    
    in  r16,icr1l  
    out  tifr,r21
  l2:  in  r21,tifr  
    sbrs  r21,icf1  
    rjmp  l2
    in  r22,icr1l  
    sub  r22,r16  
    out  portb,r22  
    out  tifr,r21
  l3:  rjmp  l3