2020-03-26 22:18:07 -05:00

76 lines
2.5 KiB
C++

/*
MQUnifiedsensor Library - reading an MQ2
Demonstrates the use a MQ2 sensor.
Library originally added 01 may 2019
by Miguel A Califa, Yersson Carrillo, Ghiordy Contreras, Mario Rodriguez
Added example
modified 23 May 2019
by Miguel Califa
Updated library usage
modified 26 March 2020
by Miguel Califa
This example code is in the public domain.
*/
//Include the library
#include <MQUnifiedsensor.h>
//Definitions
#define placa "Arduino UNO"
#define Voltage_Resolution 5
#define pin A0 //Analog input 0 of your arduino
#define type "MQ-2" //MQ2
#define ADC_Bit_Resolution 10 // For arduino UNO/MEGA/NANO
//#define calibration_button 13 //Pin to calibrate your sensor
//Declare Sensor
MQUnifiedsensor MQ2(placa, Voltage_Resolution, ADC_Bit_Resolution, pin, type);
void setup() {
//Init the serial port communication - to debug the library
Serial.begin(9600); //Init serial port
//Set math model to calculate the PPM concentration and the value of constants
MQ2.setRegressionMethod(1); //_PPM = a*ratio^b
MQ2.setA(574.25); MQ2.setB(-2.222); // Configurate the ecuation values to get LPG concentration
/*
Exponential regression:
Gas | a | b
H2 | 987.99 | -2.162
LPG | 574.25 | -2.222
CO | 36974 | -3.109
Alcohol| 3616.1 | -2.675
Propane| 658.71 | -2.168
*/
// Calibration setup
MQ2.setR0(9.659574468);
/*
//If the RL value is different from 10K please assign your RL value with the following method:
MQ2.setRL(10);
*/
/***************************** MQ Init ********************************************/
//Remarks: Configure the pin of arduino as input.
/************************************************************************************/
MQ2.init();
/***************************** MQ Init ********************************************/
//Input: setup flag, if this function are on setup will print the headers (Optional - Default value: False)
//Output: print on serial port the information about sensor and sensor readings
//Remarks: Configure the pin of arduino as input.
/************************************************************************************/
MQ2.serialDebug(true);
}
void loop() {
MQ2.update(); // Update data, the arduino will be read the voltage on the analog pin
MQ2.readSensor(); // Sensor will read PPM concentration using the model and a and b values setted before or in the setup
MQ2.serialDebug(); // Will print the table on the serial port
delay(500); //Sampling frequency
}