mirror of
https://github.com/miguel5612/MQSensorsLib.git
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223 lines
9.1 KiB
C++
223 lines
9.1 KiB
C++
/*
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MQUnifiedsensor Library - calibrating an MQ2 to MQ9
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Demonstrates the use a MQ2 sensor.
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Library originally added 01 may 2019
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by Miguel A Califa, Yersson Carrillo, Ghiordy Contreras, Mario Rodriguez
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Added example
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modified 27 May 2019
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by Miguel Califa
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Wiring:
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https://github.com/miguel5612/MQSensorsLib_Docs/blob/master/static/img/MQ_Arduino.PNG
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Please make sure arduino A0 pin represents the analog input configured on #define pin
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This example code is in the public domain.
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*/
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//Include the library
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#include <MQUnifiedsensor.h>
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/************************Hardware Related Macros************************************/
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#define Board ("Arduino Mega")
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#define Pin2 (A2) //Analog input 2 of your arduino
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#define Pin3 (A3) //Analog input 3 of your arduino
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#define Pin4 (A4) //Analog input 4 of your arduino
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#define Pin5 (A5) //Analog input 5 of your arduino
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#define Pin6 (A6) //Analog input 6 of your arduino
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#define Pin7 (A7) //Analog input 7 of your arduino
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#define Pin8 (A8) //Analog input 8 of your arduino
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#define Pin9 (A9) //Analog input 9 of your arduino
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#define PWMPin (5) // Pin connected to mosfet
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/***********************Software Related Macros************************************/
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#define RatioMQ2CleanAir (9.83) //RS / R0 = 9.83 ppm
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#define RatioMQ3CleanAir (60) //RS / R0 = 60 ppm
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#define RatioMQ4CleanAir (4.4) //RS / R0 = 4.4 ppm
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#define RatioMQ5CleanAir (6.5) //RS / R0 = 6.5 ppm
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#define RatioMQ6CleanAir (10) //RS / R0 = 10 ppm
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#define RatioMQ7CleanAir (27.5) //RS / R0 = 27.5 ppm
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#define RatioMQ8CleanAir (70) //RS / R0 = 70 ppm
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#define RatioMQ9CleanAir (9.6) //RS / R0 = 9.6 ppm
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#define ADC_Bit_Resolution (10) // 10 bit ADC
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#define Voltage_Resolution (5) // Volt resolution to calc the voltage
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#define Type ("Arduino Mega 2560") //Board used
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/*****************************Globals***********************************************/
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//Declare Sensor
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MQUnifiedsensor MQ2(Board, Voltage_Resolution, ADC_Bit_Resolution, Pin2, Type);
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MQUnifiedsensor MQ3(Board, Voltage_Resolution, ADC_Bit_Resolution, Pin3, Type);
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MQUnifiedsensor MQ4(Board, Voltage_Resolution, ADC_Bit_Resolution, Pin4, Type);
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MQUnifiedsensor MQ5(Board, Voltage_Resolution, ADC_Bit_Resolution, Pin5, Type);
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MQUnifiedsensor MQ6(Board, Voltage_Resolution, ADC_Bit_Resolution, Pin6, Type);
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MQUnifiedsensor MQ7(Board, Voltage_Resolution, ADC_Bit_Resolution, Pin7, Type);
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MQUnifiedsensor MQ8(Board, Voltage_Resolution, ADC_Bit_Resolution, Pin8, Type);
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MQUnifiedsensor MQ9(Board, Voltage_Resolution, ADC_Bit_Resolution, Pin9, Type);
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unsigned long oldTime = 0;
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void setup() {
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//Init serial port
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Serial.begin(9600);
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//init the sensor
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MQ2.init();
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MQ2.setRegressionMethod(1); //_PPM = a*ratio^b
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MQ2.setA(574.25); MQ2.setB(-2.222); // Configure the equation to to calculate LPG concentration
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MQ2.setR0(9.659574468);
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MQ3.init();
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MQ3.setRegressionMethod(1); //_PPM = a*ratio^b
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MQ3.setA(0.3934); MQ3.setB(-1.504); //Configure the equation to calculate Alcohol concentration value
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MQ3.setR0(3.86018237);
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MQ4.init();
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MQ4.setRegressionMethod(1); //_PPM = a*ratio^b
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MQ4.setA(1012.7); MQ4.setB(-2.786); // Configure the equation to to calculate CH4 concentration
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MQ4.setR0(3.86018237);
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MQ5.init();
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MQ5.setRegressionMethod(1); //_PPM = a*ratio^b
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MQ5.setA(97124); MQ5.setB(-4.918); //Configure the equation to calculate Alcohol concentration value
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MQ5.setR0(71.100304);
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MQ6.init();
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MQ6.setRegressionMethod(1); //_PPM = a*ratio^b
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MQ6.setA(2127.2); MQ6.setB(-2.526); // Configure the equation to to calculate CH4 concentration
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MQ6.setR0(13.4285714);
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MQ7.init();
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MQ7.setRegressionMethod(1); //_PPM = a*ratio^b
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MQ7.setA(99.042); MQ7.setB(-1.518); // Configure the equation to calculate CO concentration value
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MQ7.setR0(4);
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MQ8.init();
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MQ8.setRegressionMethod(1); //_PPM = a*ratio^b
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MQ8.setA(976.97); MQ8.setB(-0.688); // Configure the equation to to calculate H2 concentration
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MQ8.setR0(1);
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MQ9.init();
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MQ9.setRegressionMethod(1); //_PPM = a*ratio^b
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MQ9.setA(1000.5); MQ9.setB(-2.186); // Configure the equation to to calculate LPG concentration
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MQ9.setR0(9.42857143);
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/***************************** MQ CAlibration ********************************************/
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// Explanation:
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// In this routine the sensor will measure the resistance of the sensor supposedly before being pre-heated
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// and on clean air (Calibration conditions), setting up R0 value.
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// We recomend executing this routine only on setup in laboratory conditions.
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// This routine does not need to be executed on each restart, you can load your R0 value from eeprom.
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// Acknowledgements: https://jayconsystems.com/blog/understanding-a-gas-sensor
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Serial.print("Calibrating please wait.");
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float MQ2calcR0 = 0,
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MQ3calcR0 = 0,
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MQ4calcR0 = 0,
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MQ5calcR0 = 0,
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MQ6calcR0 = 0,
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MQ7calcR0 = 0,
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MQ8calcR0 = 0,
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MQ9calcR0 = 0;
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for(int i = 1; i<=10; i ++)
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{
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//Update the voltage Values
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MQ2.update();
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MQ3.update();
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MQ4.update();
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MQ5.update();
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MQ6.update();
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MQ7.update();
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MQ8.update();
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MQ9.update();
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MQ2calcR0 += MQ2.calibrate(RatioMQ2CleanAir);
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MQ3calcR0 += MQ2.calibrate(RatioMQ3CleanAir);
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MQ4calcR0 += MQ2.calibrate(RatioMQ4CleanAir);
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MQ5calcR0 += MQ2.calibrate(RatioMQ5CleanAir);
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MQ6calcR0 += MQ2.calibrate(RatioMQ6CleanAir);
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MQ7calcR0 += MQ2.calibrate(RatioMQ7CleanAir);
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MQ8calcR0 += MQ2.calibrate(RatioMQ8CleanAir);
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MQ9calcR0 += MQ2.calibrate(RatioMQ9CleanAir);
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Serial.print(".");
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}
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MQ2.setR0(MQ2calcR0/20);
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MQ3.setR0(MQ3calcR0/20);
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MQ4.setR0(MQ4calcR0/20);
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MQ5.setR0(MQ5calcR0/20);
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MQ6.setR0(MQ6calcR0/20);
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MQ7.setR0(MQ7calcR0/20);
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MQ8.setR0(MQ8calcR0/20);
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MQ9.setR0(MQ9calcR0/20);
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Serial.println(" done!.");
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Serial.print("Valores de R0 para cada sensor (MQ2 - MQ9):");
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Serial.print(MQ2calcR0/10); Serial.print(" | ");
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Serial.print(MQ3calcR0/10); Serial.print(" | ");
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Serial.print(MQ4calcR0/10); Serial.print(" | ");
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Serial.print(MQ5calcR0/10); Serial.print(" | ");
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Serial.print(MQ6calcR0/10); Serial.print(" | ");
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Serial.print(MQ7calcR0/10); Serial.print(" | ");
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Serial.print(MQ8calcR0/10); Serial.print(" | ");
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Serial.print(MQ9calcR0/10); Serial.println(" |");
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if(isinf(MQ2calcR0) || isinf(MQ3calcR0) || isinf(MQ4calcR0) || isinf(MQ5calcR0) || isinf(MQ6calcR0) || isinf(MQ7calcR0) || isinf(MQ8calcR0) || isinf(MQ9calcR0)) {Serial.println("Warning: Conection issue founded, R0 is infite (Open circuit detected) please check your wiring and supply"); while(1);}
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if(MQ2calcR0 == 0 || MQ3calcR0 == 0 || MQ4calcR0 == 0 || MQ5calcR0 == 0 || MQ6calcR0 == 0 || MQ7calcR0 == 0 || MQ8calcR0 == 0 || MQ9calcR0 == 0){Serial.println("Warning: Conection issue founded, R0 is zero (Analog pin with short circuit to ground) please check your wiring and supply"); while(1);}
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/***************************** MQ CAlibration ********************************************/
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//Print in serial monitor
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Serial.println("MQ2 to MQ9 - lecture");
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Serial.println("*************************** Values from MQ-board ***************************");
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Serial.println("| LPG | Alcohol | CH4 | Alcohol | CH4 | CO | H2 | LPG |");
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Serial.println("| MQ-2 | MQ-3 | MQ-4 | MQ-5 | MQ-6 | MQ-7 | MQ-8 | MQ-9 |");
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//pinMode(calibration_button, INPUT);
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}
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void loop() {
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oldTime = millis();
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while(millis() - oldTime <= (60*1000))
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{
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// VH 5 Volts
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analogWrite(5, 255); // 255 is DC 5V output
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readAllSensors();
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delay(500);
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}
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// 90s cycle
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oldTime = millis();
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while(millis() - oldTime <= (90*1000))
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{
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// VH 1.4 Volts
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analogWrite(5, 20); // 255 is 100%, 20.4 is aprox 8% of Duty cycle for 90s
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readAllSensors();
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delay(500);
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}
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}
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void readAllSensors()
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{
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//Update the voltage Values
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MQ2.update();
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MQ3.update();
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MQ4.update();
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MQ5.update();
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MQ6.update();
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MQ7.update();
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MQ8.update();
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MQ9.update();
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//Read the sensor and print in serial port
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float MQ2Lecture = MQ2.readSensor();
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float MQ3Lecture = MQ3.readSensor();
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float MQ4Lecture = MQ4.readSensor();
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float MQ5Lecture = MQ5.readSensor();
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float MQ6Lecture = MQ6.readSensor();
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float MQ7Lecture = MQ7.readSensor();
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float MQ8Lecture = MQ8.readSensor();
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float MQ9Lecture = MQ9.readSensor();
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Serial.print("| "); Serial.print(MQ2Lecture);
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Serial.print(" | "); Serial.print(MQ3Lecture);
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Serial.print(" | "); Serial.print(MQ4Lecture);
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Serial.print(" | "); Serial.print(MQ5Lecture);
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Serial.print(" | "); Serial.print(MQ6Lecture);
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Serial.print(" | "); Serial.print(MQ7Lecture);
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Serial.print(" | "); Serial.print(MQ8Lecture);
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Serial.print(" | "); Serial.print(MQ9Lecture);
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Serial.println("|");
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} |