#include &lt;Wire.h&gt;<br/>
#include &lt;LiquidCrystal_I2C.h&gt;<br/>
#include &lt;SPI.h&gt;<br/>
LiquidCrystal_I2C lcd(0x27, 16, 2);<br/>
int measurePin = 0; //Connect dust sensor to Arduino A0 pin<br/>
int ledPower = 2;   //Connect 3 led driver pins of dust sensor to Arduino D2<br/>
int samplingTime = 280;<br/>
int deltaTime = 40;<br/>
int sleepTime = 9680;<br/>
float voMeasured = 0;<br/>
float calcVoltage = 0;<br/>
float dustDensity = 0;<br/>
void setup(){<br/>
  Serial.begin(9600);<br/>
  pinMode(ledPower,OUTPUT);<br/>
  lcd.init();<br/>
  lcd.backlight();<br/>
  lcd.setCursor(5, 0);<br/>
  lcd.print("Boot...");<br/>
  lcd.setCursor(0, 1);<br/>
  for(int i=0;i<16;i++)<br/>
  {<br/>
    lcd.write(0xff);<br/>
    delay(250);<br/>
  }<br/>
}<br/>
void loop(){<br/>
  digitalWrite(ledPower,LOW); // power on the LED<br/>
  delayMicroseconds(samplingTime);<br/>
  voMeasured = analogRead(measurePin); // read the dust value<br/>
  delayMicroseconds(deltaTime);<br/>
  digitalWrite(ledPower,HIGH); // turn the LED off<br/>
  delayMicroseconds(sleepTime);<br/>
  // 0 - 5V mapped to 0 - 1023 integer values<br/>
  // recover voltage<br/>
  calcVoltage = voMeasured * (5.0 / 1024.0);<br/>
  // linear eqaution taken from [url=http://www.howmuchsnow.com/arduino/airquality/]http://www.howmuchsnow.com/arduino/airquality/[/url]<br/>
  // Chris Nafis (c) 2012<br/>
  dustDensity = 0.17 * calcVoltage - 0.1;<br/>
  Serial.print("Raw Signal Value (0-1023): ");<br/>
  Serial.print(voMeasured);<br/>
  Serial.print(" - Voltage: ");<br/>
  Serial.print(calcVoltage);<br/>
  Serial.print(" - Dust Density: ");<br/>
  Serial.println(dustDensity); // unit: mg/m3<br/>
  lcd.init();<br/>
  lcd.backlight();<br/>
  lcd.setCursor(0, 0);<br/>
  lcd.print("dustDensity:");<br/>
  lcd.setCursor(0,1);<br/>
  lcd.print(dustDensity);<br/>
  lcd.setCursor(9,1);<br/>
  lcd.print(" mg/m^3");<br/>
  delay(1000);<br/>
}<br/>