while(ReadFile(hSerial, LPVOID(szBuff), 1, &dwBytesRead, NULL))
           {
                 cout<<szBuff;
           }

#include<Windows.h>
#include<stdio.h>
#include<iostream>
using namespace std;

void main()
{
 HANDLE hSerial;
 hSerial = CreateFile(TEXT("COM3"),
   GENERIC_READ | GENERIC_WRITE,
   0,
   NULL,
   OPEN_EXISTING,
   FILE_ATTRIBUTE_NORMAL,//FILE_FLAG_OVERLAPPED,
   NULL);



if ( hSerial == INVALID_HANDLE_VALUE)
 {
  printf("Error initializing handler");
 }
 else
 {

  // Set the parameters of the handler to the serial port.
  DCB dcb = {0};

  dcb.DCBlength = sizeof(dcb);

  if ( !GetCommState(hSerial, &dcb) )
  {
   printf("Error setting parameters");
  }

  //FillMemory(&dcb, sizeof(dcb), 0);
  dcb.BaudRate = CBR_9600;
  dcb.ByteSize = 8;
  dcb.StopBits = ONESTOPBIT;
  dcb.Parity = NOPARITY;

  if ( !SetCommState(hSerial, &dcb) )
  {
   // error setting serial port state.
  }

  // Tell the program not to wait for data to show up
  COMMTIMEOUTS timeouts = {0};

  timeouts.ReadIntervalTimeout = 0;//20;
  timeouts.ReadTotalTimeoutConstant = 0;//20;
  timeouts.ReadTotalTimeoutMultiplier = 0;//50;
  timeouts.WriteTotalTimeoutConstant = 0;//100;
  timeouts.WriteTotalTimeoutMultiplier = 0;//100;

  //if ( !SetCommTimeouts(hSerial, &timeouts) )
  //{
  // printf("Error setting the timeouts");
  //}

  char szBuff[2] = "";
  DWORD dwBytesRead = 0;
  int i = 0;
  char test[] = "Bn";
 // int maxSamples = 10;
 // DWORD dwCommStatus;

  //WriteFile(hSerial, test, 2, &dwBytesRead, NULL);

  // SetCommMask(hSerial,EV_RXCHAR);
  // WaitCommEvent (hSerial, &dwCommStatus, 0);

 //  if (dwCommStatus & EV_RXCHAR)
   {
   // memset(szBuff,0,sizeof(szBuff));
       while(ReadFile(hSerial, LPVOID(szBuff), 1, &dwBytesRead, NULL))
       {
             cout<<szBuff;
       }
       cout<<endl;
   }





  CloseHandle(hSerial);
 }
    }