From c934152cd72ec769d9f00dfa51fdc222196c5ec9 Mon Sep 17 00:00:00 2001 From: miguel5612 Date: Sun, 20 Mar 2022 08:28:45 -0500 Subject: [PATCH] Added MQ135-ADS1115 example and feature --- examples/MQ135-ADS1115/MQ135-ADS1115.ino | 124 +++++++++++++++++++++++ src/MQUnifiedsensor.cpp | 8 ++ src/MQUnifiedsensor.h | 2 + 3 files changed, 134 insertions(+) create mode 100644 examples/MQ135-ADS1115/MQ135-ADS1115.ino diff --git a/examples/MQ135-ADS1115/MQ135-ADS1115.ino b/examples/MQ135-ADS1115/MQ135-ADS1115.ino new file mode 100644 index 0000000..89df8c4 --- /dev/null +++ b/examples/MQ135-ADS1115/MQ135-ADS1115.ino @@ -0,0 +1,124 @@ +/* + MQUnifiedsensor Library - reading an MQ135 + Demonstrates the use a MQ135 sensor. + Library originally added 01 may 2019 + by Miguel A Califa, Yersson Carrillo, Ghiordy Contreras, Mario Rodriguez + + Added example + modified 20 March 2022 + by Miguel Califa + + Wiring: + https://github.com/miguel5612/MQSensorsLib_Docs/blob/master/static/img/MQ_Arduino.PNG + Please make sure arduino A0 pin represents the analog input configured on #define pin + This example code is in the public domain. + + Library link https://github.com/adafruit/Adafruit_ADS1X15 +*/ +#include +#include +//Include the library +#include +//Definitions +#define placa "Arduino UNO" +#define type "MQ-135" //MQ135 +#define RatioMQ135CleanAir 3.6//RS / R0 = 3.6 ppm +float factorEscala = 0.1875F; +//#define calibration_button 13 //Pin to calibrate your sensor +//Declare Sensor +MQUnifiedsensor MQ135(placa, type); + + +// Crear objeto de la clase +Adafruit_ADS1115 ads; + +void setup(void) +{ + //Init the serial port communication - to debug the library + Serial.begin(9600); //Init serial port + delay(200); + + //Set math model to calculate the PPM concentration and the value of constants + MQ135.setRegressionMethod(1); //_PPM = a*ratio^b + + /************************************************************************************/ + MQ135.init(); + + // Iniciar el ADS1115 + ads.begin(); + + + Serial.print("Calibrating please wait."); + float calcR0 = 0; + for(int i = 1; i<=10; i ++) + { + // Obtener datos del A0 del ADS1115 + short adc0 = ads.readADC_SingleEnded(0); + float voltios = (adc0 * factorEscala)/1000.0; + MQ135.externalADCUpdate(voltios); // Update data, the arduino will read the voltage from the analog pin + calcR0 += MQ135.calibrate(RatioMQ135CleanAir); + Serial.print("."); + } + MQ135.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);} + /***************************** MQ CAlibration ********************************************/ + Serial.println("** Values from MQ-135 ****"); + Serial.println("| CO | Alcohol | CO2 | Toluen | NH4 | Aceton |"); +} + +void loop() { +// Obtener datos del A0 del ADS1115 + short adc0 = ads.readADC_SingleEnded(0); + float voltios = (adc0 * factorEscala)/1000.0; + MQ135.externalADCUpdate(voltios); // Update data, the arduino will read the voltage from the analog pin + + MQ135.setA(605.18); MQ135.setB(-3.937); // Configure the equation to calculate CO concentration value + float CO = MQ135.readSensor(); // Sensor will read PPM concentration using the model, a and b values set previously or from the setup + + MQ135.setA(77.255); MQ135.setB(-3.18); //Configure the equation to calculate Alcohol concentration value + float Alcohol = MQ135.readSensor(); // SSensor will read PPM concentration using the model, a and b values set previously or from the setup + + MQ135.setA(110.47); MQ135.setB(-2.862); // Configure the equation to calculate CO2 concentration value + float CO2 = MQ135.readSensor(); // Sensor will read PPM concentration using the model, a and b values set previously or from the setup + + MQ135.setA(44.947); MQ135.setB(-3.445); // Configure the equation to calculate Toluen concentration value + float Tolueno = MQ135.readSensor(); // Sensor will read PPM concentration using the model, a and b values set previously or from the setup + + MQ135.setA(102.2 ); MQ135.setB(-2.473); // Configure the equation to calculate NH4 concentration value + float NH4 = MQ135.readSensor(); // Sensor will read PPM concentration using the model, a and b values set previously or from the setup + + MQ135.setA(34.668); MQ135.setB(-3.369); // Configure the equation to calculate Aceton concentration value + float Acetona = MQ135.readSensor(); // Sensor will read PPM concentration using the model, a and b values set previously or from the setup + Serial.print("| "); Serial.print(CO); + Serial.print(" | "); Serial.print(Alcohol); + // Note: 200 Offset for CO2 source: https://github.com/miguel5612/MQSensorsLib/issues/29 + + + + /* + Motivation: + We have added 200 PPM because when the library is calibrated it assumes the current state of the + air as 0 PPM, and it is considered today that the CO2 present in the atmosphere is around 400 PPM. + https://www.lavanguardia.com/natural/20190514/462242832581/concentracion-dioxido-cabono-co2-atmosfera-bate-record-historia-humanidad.html + */ + Serial.print(" | "); Serial.print(CO2 + 400); + Serial.print(" | "); Serial.print(Tolueno); + Serial.print(" | "); Serial.print(NH4); + Serial.print(" | "); Serial.print(Acetona); + Serial.println(" |"); + /* + Exponential regression: + GAS | a | b + CO | 605.18 | -3.937 + Alcohol | 77.255 | -3.18 + CO2 | 110.47 | -2.862 + Tolueno | 44.947 | -3.445 + NH4 | 102.2 | -2.473 + Acetona | 34.668 | -3.369 + */ + + delay(500); //Sampling frequency +} \ No newline at end of file diff --git a/src/MQUnifiedsensor.cpp b/src/MQUnifiedsensor.cpp index 4cf21a8..60e7ee5 100644 --- a/src/MQUnifiedsensor.cpp +++ b/src/MQUnifiedsensor.cpp @@ -9,6 +9,10 @@ MQUnifiedsensor::MQUnifiedsensor(String Placa, float Voltage_Resolution, int ADC this-> _VOLT_RESOLUTION = Voltage_Resolution; this-> _ADC_Bit_Resolution = ADC_Bit_Resolution; } +MQUnifiedsensor::MQUnifiedsensor(String Placa, String type) { + Placa.toCharArray(this->_placa, 20); + type.toCharArray(this->_type, 6); +} void MQUnifiedsensor::init() { pinMode(_pin, INPUT); @@ -108,6 +112,10 @@ void MQUnifiedsensor::update() { _sensor_volt = this->getVoltage(); } +void MQUnifiedsensor::externalADCUpdate(float volt) +{ + _sensor_volt = volt; +} float MQUnifiedsensor::validateEcuation(float ratioInput) { //Serial.print("Ratio input: "); Serial.println(ratioInput); diff --git a/src/MQUnifiedsensor.h b/src/MQUnifiedsensor.h index fbbb29a..123b46d 100644 --- a/src/MQUnifiedsensor.h +++ b/src/MQUnifiedsensor.h @@ -14,10 +14,12 @@ class MQUnifiedsensor { public: MQUnifiedsensor(String Placa = "Arduino", float Voltage_Resolution = 5, int ADC_Bit_Resolution = 10, int pin = 1, String type = "CUSTOM MQ"); + MQUnifiedsensor(String Placa = "Arduino", String type = "CUSTOM MQ"); //Functions to set values void init(); void update(); + void externalADCUpdate(float volt); void setR0(float R0 = 10); void setRL(float RL = 10); void setA(float a);