Building a PM 2.5 dust sensor with Arduino and SDS011

What you need:

1. 1 x An Arduino board
2. 1 x Beadboard
3. 1 x LED

Libraries can be download on this link: https://my.pcloud.com/publink/show?code=XZ2WdMkZi4NSB0cwO5hUeE8YkAfwNzACfowX

PM 2.5 Sensor

Circuit Wiring

Code for Arduino IDE

1. Open Arduino IDE > install all required libraries > write down the following code:

#include <Wire.h>
#include <LCD.h>
#include <LiquidCrystal_I2C.h>
#include "SdsDustSensor.h"
#define I2C_ADDR 0x3F // 
#define BACKLIGHT_PIN 3
int rxPin = 10;
int txPin = 11;
SdsDustSensor sds(rxPin, txPin);
LiquidCrystal_I2C lcd(I2C_ADDR,2,1,0,4,5,6,7);
void setup()
{
      Serial.begin(9600);
      sds.begin();
      lcd.begin (16,2);
      // Switch on the backlight
      lcd.setBacklightPin(BACKLIGHT_PIN,POSITIVE);
      lcd.setBacklight(HIGH);
}
void loop()
{
  PmResult pm = sds.readPm();
  int AQI;
  String state;
  if (pm.isOk()) {
      Serial.print("PM2.5 = ");
      Serial.print(pm.pm25);
      Serial.print(", PM10 = ");
      Serial.println(pm.pm10);
      lcd.home (); 
      lcd.setCursor(0,0); 
      lcd.print("PM 2.5:");
      lcd.setCursor(8,0);
      lcd.print(pm.pm25);
      lcd.print(" ");
      lcd.setCursor(0,1); 
      getAQI(pm.pm25, &AQI, &state);
      lcd.print("AQI:");
      lcd.setCursor(4,1);
      lcd.print(AQI);
      Serial.print(AQI);
      lcd.print(" ");
      lcd.setCursor(8,1);
      lcd.print(state);
      // if you want to just print the measured values, you can use toString() method as well
      Serial.println(pm.toString());
  } else {
      Serial.print("Could not read values from sensor, reason: ");
      Serial.println(pm.statusToString());
  }
  delay(500);
}
void getAQI(float pm25, int* aqi, String* state){
  // aqi = Ilow + (C-Clow)*(Ihigh-Ilow)/(Chigh-Clow) with I=aqi and C=concentration
  if(pm25 < 12){
      *aqi = 0 + (pm25-0)*(50.0-0)/(12-0);
      *state = "Good";
  }else if(pm25 < 35){
      *aqi = 51 + (pm25-13)*(100.0-51)/(35-13);
      *state = "Moderate";
  }else if(pm25 < 55){
      *aqi = 101 + (pm25-36)*(150.0-101)/(55-36);
      *state = "Beware";  
  }else if(pm25 < 150){
      *aqi = 151 + (pm25-56)*(200.0-151)/(150-56);
      *state = "Unhealthy";
  }else if(pm25 < 250){
      *aqi = 201 + (pm25-151)*(300.0-201)/(250-151);
      *state = "Very UH";
  }else{
      *aqi = 300 + (pm25-250)*(500.0-300)/(500-250);
      *state = "Harzard";
  } 
}

2. Before compiling the code, choose board type and specify the port

Screenshot of Code Compilation

Here is how to convert AQI to microgram per ug/m3 for PM2.5 particle