void setup() {
  // put your setup code here, to run once:
  volatile char *dir;
  dir = 0x30;
  *dir = 0xFF;
}

void loop() {
  // put your main code here, to run repeatedly: 
  volatile char *out;
  out = 0x31;
  *out = 0b01001111; //any number to be displayed put here//try 0x01,0x02,0x04,0x08..
}