Code: Photon PMS1003 Dust Sensor

// This #include statement was automatically added by the Particle IDE.
#include <ParticleSoftSerial.h>

#include <Arduino.h>
#define LENG 31   //0x42 + 31 bytes equal to 32 bytes
unsigned char buf[LENG];

//unsigned char myChar = 255;

int PM01Value=0;          //define PM1.0 value of the air detector module
int PM2_5Value=0;         //define PM2.5 value of the air detector module
int PM10Value=0;         //define PM10 value of the air detector module

ParticleSoftSerial PMSerial(4, 5); // RX, TX

void setup()
{
  PMSerial.begin(9600);   
  PMSerial.setTimeout(1500);    
  Serial.begin(9600);
}

void loop()
{
  if(PMSerial.find("B")){    
    PMSerial.readBytes((char*)buf,LENG);

    if(buf[0] == 0x4d){
    //if(buf[0] == "A"){
      if(checkValue(buf,LENG)){
        PM01Value=transmitPM01(buf); //count PM1.0 value of the air detector module
        PM2_5Value=transmitPM2_5(buf);//count PM2.5 value of the air detector module
        PM10Value=transmitPM10(buf);//count PM10 value of the air detector module 
        
         Particle.publish("dust", String(PM2_5Value) + " ug/m3 ");

      }           
    } 
  }
  

  static unsigned long OledTimer=millis();  
    if (millis() - OledTimer >=1000) 
    {
      OledTimer=millis(); 
      
      Serial.print("PM1.0: ");  
      Serial.print(PM01Value);
      Serial.println("  ug/m3");            
    
      Serial.print("PM2.5: ");  
      Serial.print(PM2_5Value);
      Serial.println("  ug/m3");     
      
      Serial.print("PM1 0: ");  
      Serial.print(PM10Value);
      Serial.println("  ug/m3");   
      Serial.println();
    }
  
}
char checkValue(unsigned char *thebuf, char leng)
{  
  char receiveflag=0;
  int receiveSum=0;

  for(int i=0; i<(leng-2); i++){
  receiveSum=receiveSum+thebuf[i];
  }
  receiveSum=receiveSum + 0x42;
 
  if(receiveSum == ((thebuf[leng-2]<<8)+thebuf[leng-1]))  //check the serial data 
  {
    receiveSum = 0;
    receiveflag = 1;
  }
  return receiveflag;
}

int transmitPM01(unsigned char *thebuf)
{
  int PM01Val;
  PM01Val=((thebuf[3]<<8) + thebuf[4]); //count PM1.0 value of the air detector module
  return PM01Val;
}

//transmit PM Value to PC
int transmitPM2_5(unsigned char *thebuf)
{
  int PM2_5Val;
  PM2_5Val=((thebuf[5]<<8) + thebuf[6]);//count PM2.5 value of the air detector module
  return PM2_5Val;
  }

//transmit PM Value to PC
int transmitPM10(unsigned char *thebuf)
{
  int PM10Val;
  PM10Val=((thebuf[7]<<8) + thebuf[8]); //count PM10 value of the air detector module  
  return PM10Val;
}