#define SENSOR SENSOR_1
#define DARK 40
#define LIGHT 50
#define COUNTER 0
#define LOGSIZE 300

// reserve space for COUNTER 0
#pragma reserve 0

task main ()
{
  int i;
  PlaySound(SOUND_DOUBLE_BEEP);
  SetSensor(SENSOR, SENSOR_LIGHT);
  CreateDatalog(LOGSIZE);
  for (i=0; i<LOGSIZE/2; i++) {
    ClearCounter(COUNTER);
    until (SENSOR < DARK);
    while (SENSOR < DARK) IncCounter(COUNTER);
    AddToDatalog(Counter(COUNTER));
    ClearCounter(COUNTER);
    until (SENSOR > LIGHT);
    while (SENSOR > LIGHT) IncCounter(COUNTER);
    AddToDatalog(Counter(COUNTER));
  }
  PlaySound(SOUND_DOUBLE_BEEP);      
}