void setup() {
  // put your setup code here, to run once:
  volatile long i,j;
  volatile char *dirF,*dirD,*dirA,*dirK;
  dirA=0x21; dirD=0x2a; dirF=0x30;
  *dirD=0xff;
  *dirA=0xff;
  *dirF=0xff;
  volatile char *outF=0x31,*outD,*outA;
  outF=0x31;
  outD=0x2b;
  outA=0x22;
  dirK=0x107;
  *dirK=0x00;
  volatile char *inp;
  inp=0x106;
  while(1){
    for(i=0;i<4;i++){
      *outF=1<<i;
      *outA=*inp;
      if(*inp!=0){
        *outD=1<<i;
        for(j=0;j<1000000;j++);
        *outD=0;
      }
    }
  }

}

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

}