#define Filoguide SENSOR_1
#define Steer OUT_A
#define Drive OUT_C
#define Threshold 5
#define HysterVal 10


task main ()
{
  int Offset;
  int Hyster=0;
  int Diff;

  SetSensor (Filoguide, SENSOR_LIGHT);

  Offset = Filoguide;

  OnRev (Drive);
  while (true)
  {
    Diff = Filoguide - Offset - Hyster;
    if (Diff >= -Threshold && Diff <= Threshold)
    {
      Off (Steer);
      Hyster = 0;
    }
    else
    {
      if (Diff < 0)
      {
        OnFwd (Steer);
        Hyster=-HysterVal;
      }
      else
      {
        OnRev (Steer);
        Hyster=HysterVal;
      }

    }
  }
}