#include <mc9s12dp512.h>
void main(void)
  {
    unsigned char z;
    DDRB = 0x00;				
    DDRA = 0xFF;				
    while(1)				
      {
        z = PORTB;   			
        z = z & 0x3; 			
        switch(z)  			
          {
           case(0):
            {
             PORTA = '0';		
             break;
            }
           case(1):
            {
             PORTA = '1';		
             break;
            }
           case(2):
            {
             PORTA = '2';		
             break;
            }
           case(3):
            {
             PORTA = '3';		
             break;
            }
          }
      }
  }