#include <avr\io.h>    
  #include <avr\interrupt.h>
  
  isr(usart_rxc_vect)
  {  
     portb = udr ;
  }
  
  int main (void)
  {
     ddrb = 0xff;        
      ucsrb = (1<<rxen)|(1<<rxcie);  
     ucsrc = (1<< ucsz1)|(1<<ucsz0)|(1<<ursel);
      ubrrl = 0x33 ;
      sei();          
  
      while (1);        
  
      return 0 ;
  }