Com порт не получается ReadFile

#include <iostream>
#include <conio.h>
#include <windows.h>
#include <fstream>
#include <stdio.h>
using namespace std;
char         *buf_out="1";
char         *buf_in;
DWORD         bc;
DWORD         cb;
bool a;
 
 
int main()
{
    HANDLE hCOM=CreateFile(L"COM3",GENERIC_ALL,0,NULL,OPEN_EXISTING, 0 ,NULL);
    cout << "com otcrit";
 DCB dcb;
   dcb.DCBlength = sizeof(DCB);
 
    dcb.BaudRate = CBR_9600;
    dcb.fBinary = TRUE;
    dcb.fParity = FALSE;
    dcb.fOutxCtsFlow = FALSE;
    dcb.fOutxDsrFlow = FALSE;
    dcb.fDtrControl = DTR_CONTROL_ENABLE;
    dcb.fDsrSensitivity = 0;
    dcb.fTXContinueOnXoff  = FALSE;
    dcb.fOutX = TRUE;
    dcb.fInX = TRUE;
    dcb.fErrorChar = FALSE;
    dcb.fNull = FALSE;
    dcb.fRtsControl = RTS_CONTROL_ENABLE;
    dcb.fAbortOnError = FALSE;  
    dcb.wReserved = 0;
    dcb.XonLim = 1;
    dcb.XoffLim = 100;
    dcb.Parity = NOPARITY;
    dcb.StopBits =ONESTOPBIT;
    dcb.XonChar = 17;
    dcb.XoffChar = 29;
    dcb.ErrorChar = 0;
    dcb.EofChar = 0;
    dcb.EvtChar = 0;
    cout << "com konfigurirovan";
 
    
COMMTIMEOUTS comtimeouts; 
        comtimeouts.ReadIntervalTimeout = 8;
        comtimeouts.ReadTotalTimeoutMultiplier = 50;
        comtimeouts.ReadTotalTimeoutConstant = 3;
        comtimeouts.WriteTotalTimeoutMultiplier = 100;
        comtimeouts.WriteTotalTimeoutConstant = 4;
        cout << "com timeouts";
 FlushFileBuffers( hCOM );
 WriteFile(hCOM,buf_out,strlen(buf_out),&bc,NULL);
 cout << "com wrote";
 
 ReadFile(hCOM,buf_in,strlen(buf_in),&cb,NULL);
    
 
 CloseHandle(hCOM);
 
    system ("pause");
return 0;
 
}