void setup()
{
  volatile char *dirf,*outf;
  volatile char *dirk,*ink;
  dirf=0x30; outf=0x31;
  dirk=0x107; ink=0x106;
  *dirf=0xFF; *dirk=0x00;
  volatile char switches;
 loop: while(1)
  {
    switches=*ink;
    if((switches & 1) == 1)
    {
      while(1)
      {
        switches=*ink;
        if((switches & 8) == 8)
        {
          while(1)
          {
            switches=*ink;
            if((switches & 64) == 64)
            {
              while(1)
              {
                switches=*ink;
                if((switches & 32) == 32)
                {
                  *outf=16;
                  goto loop;
                }
              }
            }
          }
        }
      }
    }
        else
   {
        switches=*ink;
      if((switches & 8) == 8)
      {
        while(1)
        {
          switches=*ink;
          if((switches & 64) == 64)
          {
            while(1)
            {
              switches=*ink;
              if((switches & 32) == 32)
              {
                while(1)
                {
                  switches=*ink;
                  if((switches & 128) == 128)
                  {
                      *outf=0;
                      goto loop;
                  }
                }
              }
            }
          }
        }
      }
    }
  }
  }

void loop()
{

}