#include <MQUnifiedsensor.h>

#define         Board                   ("Arduino UNO")
#define         Pin                     (A0)  

#define         Type                    ("MQ-2") 
#define         Voltage_Resolution      (5)
#define         ADC_Bit_Resolution      (10) 
#define         RatioMQ2CleanAir        (9.83) 

MQUnifiedsensor MQ2(Board, Voltage_Resolution, ADC_Bit_Resolution, Pin, Type);

void setup() {
  Serial.begin(9600); 

  MQ2.setRegressionMethod(1); 
  MQ2.setA(574.25); MQ2.setB(-2.222); 
  
  MQ2.init(); 
  
  Serial.print("Calibrating please wait.");
  float calcR0 = 0;
  for(int i = 1; i<=10; i ++)
  {
    MQ2.update(); 
    calcR0 += MQ2.calibrate(RatioMQ2CleanAir);
    Serial.print(".");
  }
  MQ2.setR0(calcR0/10);
  Serial.println("  done!.");
  
  if(isinf(calcR0)) {Serial.println("Warning: Conection issue, R0 is infinite (Open circuit detected) please check your wiring and supply"); while(1);}
  if(calcR0 == 0){Serial.println("Warning: Conection issue found, R0 is zero (Analog pin shorts to ground) please check your wiring and supply"); while(1);}

  MQ2.serialDebug(true);
}

void loop() {
  MQ2.update(); 
  MQ2.readSensor(); 
  MQ2.serialDebug(); 
  delay(500); 
}