unsigned char *led;
unsigned char *leddir;

int main(void) {
  led = (unsigned char*) 0x38;
  leddir = (unsigned char*) 0x37;
  *leddir = 0xff;
  
  while (1) {
    /* Acende... */
    led_on();
    unsigned int i;
    for(i=0; i < 0xffff; i++);
    /* Apaga! :-D */
    led_off();
    for(i=0; i < 0xffff; i++);
  }
  return 0;
}

int led_on(void) {
  *led = 0xff;
  return 0;
}

int led_off(void) {
  *led = 0x0;
  return 0;
}