#include <avr/io.h>        
  
  int main(void) 
  {  
      unsigned char x, y;
      unsigned char mybyte = 0x29;
  
    ddrb = ddrc = 0xff;    
      x = mybyte & 0x0f;    
      portb = x | 0x30;    
      y = mybyte & 0xf0;    
      y = y >> 4;        
      portc = y | 0x30;    
  
    return 0;
  }