Hamamatsu-Photonics S9705 Lx-Freq converter IC

FreqLx2.ino

// S9705 Lx meter

int input=5;

int high_time;
int low_time;
// float time_period;
// float frequency;
long int time_period;
long int frequency;

void setup()
{
  pinMode(input,INPUT);
  Serial.begin(9600);
  Serial.println("Frequency Counter");

}
void loop() {
  high_time=pulseIn(input,HIGH);
  low_time=pulseIn(input,LOW);

  time_period=high_time+low_time;
//  time_period=time_period/1000;
//  frequency=1000/time_period;

  frequency=1000000/time_period;


  // Serial.print(frequency); Serial.print(" Hz ");
  // Serial.print(frequency/500); Serial.println(" Lx");
  Serial.println(frequency/500);

  delay(200);
}