void loop()
{
  lcd.setCursor(0,0);
  lcd.print(F("HR   ="));
  lcd.setCursor(0,1);
  lcd.print(F("SPO2 ="));    
  ppg.heartrateAndOxygenSaturation(/**SPO2=*/&SPO2, /**SPO2Valid=*/&SPO2Valid, /**heartRate=*/&HeartRate, /**heartRateValid=*/&HeartRateValid);
  lcd.setCursor(8,0);
  lcd.print(HeartRate, DEC);
  lcd.setCursor(8,1);
  lcd.print(SPO2, DEC);
  Serial.print(F("HeartRateValid = "));
  Serial.print(HeartRateValid, DEC);
  Serial.print(F(" , SPO2Valid = "));
  Serial.print(SPO2Valid, DEC);
 // ppg.heartrateAndOxygenSaturation(/**SPO2=*/&SPO2, /**SPO2Valid=*/&SPO2Valid, /**heartRate=*/&HeartRate, /**heartRateValid=*/&HeartRateValid);
}