void setup() {
  // put your setup code here, to run once:
  //here setting the pin to high output 
  volatile char *dir;
  //address
  dir=0x30;
  //data
  *dir|=0xFF;

}
void set(volatile char *out){
  *out|=0xFF;
}
void reset(volatile char *out){
  *out&=0x00;
}
void loop() {
  // put your main code here, to run repeatedly:
  volatile char out,y;
  out=0x31;
  y=&out;
  unsigned int res=0;
  res=2;
  switch(res){
       case 1:
       set(out);
       break;
       case 2:
       reset(out);
       break;
       default:
       set(out);
       break;
}
}