void setup() {
  // put your setup code here, to run once:
  volatile char *dirf,*dirk;
  volatile char *outf,*outk;

  dirf = 0x30;    dirk = 0x107;
   outf = 0x31;   outk = 0x108;

  *dirf = 0x03;  
  *dirk = 0x03;

   *outk = 0x00;  //0 also means ground
   *outf = 0x01;  //try 0x02 and 0x03
}

void loop() {
  // put your main code here, to run repeatedly:

}