Air Quality Monitor (PM 2.5, Temperature & Humidity Sensor) SKU:SEN0233 : Particle Reading Issue

Hi Everyone.

I am using

SKU:SEN0233 connected with DFDuino Uno
 

connected as follows.

I am also using the default sample code below.

/*!
* @file  SEN0233.ino
* @brief Air Quality Monitor (PM 2.5, HCHO, Temperature & Humidity)
* @n Get the module here: https://www.dfrobot.com/product-1612.html
* @n This example is to detect formaldehyde, PM2.5, temperature and humidity in the environment.
* @copyright  Copyright (c) 2010 DFRobot Co.Ltd (http://www.dfrobot.com)
* @license  The MIT License (MIT)
* @author  [lijun]([email protected])
* @version  V1.0
* @date  2017-03-01
*/

#include <SoftwareSerial.h>

char col;
unsigned int PMSa1 = 0, PMSa2_5 = 0, PMSa10 = 0, FMHDSa = 0, TPSa = 0, HDSa = 0, PMSb1 = 0, PMSb2_5 = 0, PMSb10 = 0, FMHDSb = 0, TPSb = 0, HDSb = 0;
unsigned int PMS1 = 0,PMS2_5 = 0,PMS10 = 0, FMHDS = 0, TPS = 0, HDS = 0, CR1 = 0, CR2 = 0;
unsigned char bufferRTT[32] = {}; //serial receive data
char tempStr[15];

SoftwareSerial mySerial(10, 11); // RX, TX

void setup()
{
 Serial.begin(115200);
 mySerial.begin(9600);
}

void loop()
{

 while (!mySerial.available());
 while (mySerial.available() > 0) //Check whether there is any serial data
 {
   for (int i = 0; i < 32; i++)
   {
     col = mySerial.read();
     bufferRTT[i] = (char)col;
     delay(2);
   }

   mySerial.flush();

   CR1 = (bufferRTT[30] << 8) + bufferRTT[31];
   CR2 = 0;
   for (int i = 0; i < 30; i++)
     CR2 += bufferRTT[i];
   if (CR1 == CR2)               //Check
   {
     PMSa1 = bufferRTT[10];      //Read PM1 high 8-bit data
     PMSb1 = bufferRTT[11];      //Read PM1 low 8-bit data
     PMS1 = (PMSa1 << 8) + PMSb1;   //PM1 data

     PMSa2_5 = bufferRTT[12];      //Read PM2.5 high 8-bit data
     PMSb2_5 = bufferRTT[13];      //Read PM2.5 low 8-bit data
     PMS2_5 = (PMSa2_5 << 8) + PMSb2_5;   //PM2.5 data

     PMSa10 = bufferRTT[14];      //Read PM10 high 8-bit data
     PMSb10 = bufferRTT[15];      //Read PM10 low 8-bit data
     PMS10 = (PMSa10 << 8) + PMSb10;   //PM10 data

     TPSa = bufferRTT[24];      //Read temperature high 8-bit data
     TPSb = bufferRTT[25];      //Read temperature low 8-bit data
     TPS = (TPSa << 8) + TPSb;   //Temperature data

     HDSa = bufferRTT[26];      //Read humidity high 8-bit data
     HDSb = bufferRTT[27];      //Read humidity low 8-bit data
     HDS = (HDSa << 8) + HDSb;   //Humidity data
   }
   else
   {
     PMS1 = 0;
     PMS2_5 = 0;
     PMS10 = 0;
     TPS = 0;
     HDS = 0;
   }
 }

 Serial.println("-----------------------uart--------------------------");
 Serial.print("Temp : ");
 sprintf(tempStr, "%d%d.%d", TPS / 100, (TPS / 10) % 10, TPS % 10);
 Serial.print(tempStr);
 Serial.println(" C");              //Display temperature
 Serial.print("RH   : ");
 sprintf(tempStr, "%d%d.%d", HDS / 100, (HDS / 10) % 10, HDS % 10);
 Serial.print(tempStr);            //Display humidity
 Serial.println(" %");               //%
 Serial.print("PM1.0: ");
 Serial.print(PMS1);
 Serial.println(" ug/m3"); //Display PM1.0 unit  ug/m³ 
 Serial.print("PM2.5: ");
 Serial.print(PMS2_5);
 Serial.println(" ug/m3"); //Display PM2.5 unit  ug/m³ 
 Serial.print("PM 10: ");
 Serial.print(PMS10);
 Serial.println(" ug/m3"); //Display PM 10 unit  ug/m³ 
}
 

I am getting a serial response from Arduino serial monitoring but the values are too small to be accurate.

09:39:30.823 -> -----------------------uart--------------------------

09:39:30.823 -> Temp : 21.6 C

09:39:30.823 -> RH   : 52.3 %

09:39:30.865 -> PM1.0: 1 ug/m3

09:39:30.865 -> PM2.5: 1 ug/m3

09:39:30.865 -> PM 10: 1 ug/m3

09:39:31.740 -> -----------------------uart--------------------------

09:39:31.740 -> Temp : 21.6 C

09:39:31.740 -> RH   : 52.3 %

09:39:31.740 -> PM1.0: 4 ug/m3

09:39:31.740 -> PM2.5: 4 ug/m3

09:39:31.786 -> PM 10: 4 ug/m3

did anybody experience this before? the product is also new for both the controller and the sensor.
Thank you