EICRB = (1<<ISC71);	            //INT7 falling edge activate
  EIFR = (1<<INTF7);	            //clear pending interrupts
  EIMSK |= (1<<INT7);	            //INT7 enable
  __enable_interrupt();             //interrupts enable

#pragma vector = INT7_vect
__interrupt void Int7_Service_Routine(void)
{
  .......
}