Project #15: Environment – MQ-135 Gas Sensor – Mk40

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#DonLucElectronics #DonLuc #MQ135 #AHT20 #Environment #FireBeetle2ESP32E #ESP32 #Display #IoT #Project #Fritzing #Programming #Electronics #Microcontrollers #Consultant

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MQ-135 Gas Sensor

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MQ-135 Gas Sensor

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MQ-135 Gas Sensor

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MQ-135 Gas Sensor

They are used in air quality control equipments for buildings. offices, home, etc, are suitable for detecting of NH3, NOx, Alcohol, Benzene, Smoke, CO2, Etc…

The sensor itself is enclosed in two layers of stainless steel mesh which ensures that the internal heating element does not cause an explosion since there may be flammable gases present in its working environment, and it also filters suspended particles so that only gases enter the chamber.

DL2605Mk03

1 x DFRobot FireBeetle 2 ESP32-E
1 x Fermion: 3.5” 480×320 TFT LCD Capacitive
1 x GDL Line 10 CM
1 x MQ-135 Gas Sensor
1 x Gravity: AHT20 Temperature and Humidity Sensor
1 x Gravity: IO Shield for FireBeetle 2
1 x Terminal Block Board for FireBeetle 2 ESP32-E IoT
1 x Lithium Ion Battery – 1000mAh
1 x USB 3.0 to Type-C Cable

DL2605Mk03p

DL2605Mk03p.ino

/****** Don Luc Electronics © ******
Software Version Information
Project #15: Environment - MQ-135 Gas Sensor - Mk40
15-40
DL2605Mk03p.ino
DL2605Mk03
1 x DFRobot FireBeetle 2 ESP32-E
1 x Fermion: 3.5” 480x320 TFT LCD Capacitive
1 x GDL Line 10 CM
1 x MQ-135 Gas Sensor
1 x Gravity: AHT20 Temperature and Humidity Sensor
1 x Gravity: IO Shield for FireBeetle 2
1 x Terminal Block Board for FireBeetle 2 ESP32-E IoT
1 x Lithium Ion Battery - 1000mAh
1 x USB 3.0 to Type-C Cable
*/

// Include the Library Code
// EEPROM Library to Read and Write EEPROM with Unique ID for Unit
#include "EEPROM.h"
// DFRobot Display GDL API
#include <DFRobot_GDL.h>
// AHT20 Humidity and Temperature Sensor
#include <DFRobot_AHT20.h>
// MQ-135 Gas Sensor
#include <MQ135.h>

// MQ-135 Gas Sensor
int iMQ135 = A0;
int iValMQ135 = 0;

// AHT20 Humidity and Temperature Sensor
DFRobot_AHT20 aht20;
// AHT20 Humidity and Temperature Sensor
float h = 0;
float t = 0;

// Defined ESP32
#define TFT_DC  D2
#define TFT_CS  D6
#define TFT_RST D3

/*dc=*/ /*cs=*/ /*rst=*/
// DFRobot Display 320x480
DFRobot_ILI9488_320x480_HW_SPI screen(TFT_DC, TFT_CS, TFT_RST);

// Software Version Information
// EEPROM Unique ID Information
#define EEPROM_SIZE 64
String uid = "";

// Software Version Information
String sver = "15-40";

void loop() {
  
  // isMQ135
  isMQ135();
  
  // AHT20 Humidity and Temperature Sensor
  isHT();

  // isDisplay MQ-135
  isDisplayMQ135();

  // Delay 2 Second
  delay( 2000 );

}

getDisplay.ino

// DFRobot Display 320x480
// DFRobot Display 320x480 - UID
void isDisplayUID(){

  // DFRobot Display 320x480
  // Text Display
  // Text Wrap
  screen.setTextWrap(false);
  // Rotation
  screen.setRotation(3);
  // Fill Screen => black
  screen.fillScreen(0x0000);
  // Text Color => white
  screen.setTextColor(0xffff);
  // Font => Free Sans Bold 12pt
  screen.setFont(&FreeSansBold12pt7b);
  // TextSize => 1.5
  screen.setTextSize(1.5);
  // Don Luc Electronics
  screen.setCursor(0, 30);
  screen.println("Don Luc Electronics");
  // Tilt Switch
  screen.setCursor(0, 60);
  screen.println("MQ-135 Gas Sensor");
  // Version
  screen.setCursor(0, 90);
  screen.println("Version");
  screen.setCursor(0, 120);
  screen.println( sver );
  // EEPROM
  screen.setCursor(0, 150);
  screen.println("EEPROM");
  screen.setCursor(0, 180);
  screen.println( uid );

}
// isDisplay MQ135
void isDisplayMQ135(){

  // DFRobot Display 320x480
  // Text Display
  // Text Wrap
  screen.setTextWrap(false);
  // Rotation
  screen.setRotation(3);
  // Fill Screen => white
  screen.fillScreen(0xffff);
  // Text Color => blue
  screen.setTextColor(0x001F);
  // Font => Free Sans Bold 12pt
  screen.setFont(&FreeSansBold12pt7b);
  // TextSize => 1.5
  screen.setTextSize(1.5);
  // Vibration Senso
  screen.setCursor(0, 30);
  screen.println("MQ-135 Gas Sensor");
  // Humidity
  screen.setCursor(0, 70);
  screen.println("Humidity");
  screen.setCursor(0, 100);
  screen.print( h );
  screen.setCursor(65, 100);
  screen.println( "%RH" );
  // Temperature
  screen.setCursor(0, 140);
  screen.println("Temperature");
  screen.setCursor(0, 170);
  screen.print( t );
  screen.setCursor(65, 170);
  screen.println( "C" );
  // MQ7 Carbon Monoxide
  screen.setCursor(0, 210);
  screen.println("MQ-135 Gas Sensor");
  screen.setCursor(0, 240);
  screen.print( iValMQ135 );
  screen.setCursor(65, 240);
  screen.println( "ppm" );
  
}

getEEPROM.ino

// isUID EEPROM Unique ID
void isUID()
{
  
  // Is Unit ID
  uid = "";
  for (int x = 0; x < 7; x++)
  {
    uid = uid + char(EEPROM.read(x));
  }
  
}

getgetHT.ino

// AHT20 Humidity and Temperature Sensor
void isHT(){

  if(aht20.startMeasurementReady(true)){

    // Humidity
    h = aht20.getHumidity_RH();
  
    // Temperature
    t = aht20.getTemperature_C();
    
   }
  
}

ggetMQ135.ino

// MQ135
// isMQ135
void isMQ135(){

  iValMQ135 = analogRead( iMQ135 );

}

setup.ino

// Setup
void setup()
{
 
  // Delay
  delay( 100 );

   // EEPROM Size
  EEPROM.begin(EEPROM_SIZE);
  
  // EEPROM Unique ID
  isUID();

  // Delay
  delay(100);

  // DFRobot Display 320x480
  screen.begin();

  // Delay
  delay( 100 );

  // AHT20 Humidity and Temperature Sensor
  aht20.begin();

  // Delay
  delay( 100 );

  // DFRobot Display 320x480 - UID
  // Don Luc Electronics
  // Version
  // EEPROM
  isDisplayUID();

  // Wait for the sensor to heat up for 20 seconds
  delay( 20000 );

}

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