// Sonar sensor range computation/display program.

 int x;
 task main ()
 {
  int range;
  SetSensor (SENSOR_1, SENSOR_LIGHT);
  SetUserDisplay (x, 0);
  OnFwd(OUT_A+OUT_C);
  start drive;
  
   while(true)
   {
    range = (SENSOR_1/2) + 6;
    x = range;
    Wait(5);
   }
 }
  
  task drive()
  {
   until(x == 50);
   Off(OUT_A+OUT_C);
   repeat(5)
    {
     PlaySound (SOUND_CLICK);
     Wait(30);
    }
   OnFwd(OUT_A+OUT_C);
     
   until(x == 40);
   Off(OUT_A+OUT_C);
   repeat(4)
    {
     PlaySound (SOUND_CLICK);
     Wait(30);
    }
   OnFwd(OUT_A+OUT_C);
   
   until(x == 30);
   Off(OUT_A+OUT_C);
   repeat(3)
    {
     PlaySound (SOUND_CLICK);
     Wait(30);
    }
   OnFwd(OUT_A+OUT_C);
   
   until(x == 20);
   Off(OUT_A+OUT_C);
   repeat(2)
    {
     PlaySound (SOUND_CLICK);
     Wait(30);
    }
   OnFwd(OUT_A+OUT_C);
   
   until(x == 10);
   Off(OUT_A+OUT_C);
   repeat(1)
    {
     PlaySound (SOUND_CLICK);
     Wait(30);
    }
   OnFwd(OUT_A+OUT_C);
   
   until(x == 6);
   Off(OUT_A+OUT_C);
  }