Re: Strange serial port error

From:
clinisbut <clinisbut@gmail.com>
Newsgroups:
microsoft.public.vc.mfc
Date:
Fri, 27 Jun 2008 03:43:37 -0700 (PDT)
Message-ID:
<08f02d84-d180-4a84-8c6b-9eea6655b0ba@56g2000hsm.googlegroups.com>
And here MySerial.cpp:

// MySerial.cpp : implementation file
//

#include "stdafx.h"
#include "uart3.h"
#include "MySerial.h"
#include <vector>
#define MAX_BUFFER_SIZE_MYSERIAL 64
#define READING 0
#define WRITING 1

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

/////////////////////////////////////////////////////////////////////////////
// MySerial

IMPLEMENT_DYNCREATE(MySerial, CWinThread)

//! Constructor
MySerial::MySerial()
{
    opened= FALSE;
    init = FALSE;
}

//! Destructor
MySerial::~MySerial()
{
    //CloseHandle(ShutdownEvent);
    //CloseHandle(ReadEvent);
    //CloseHandle(WriteEvent);

    // Wait for the thread to exit before deleting
    //WaitForSingleObject( this->m_hThread, INFINITE );
}

/*! \brief Inits member's class.

    Due the use of threads, initialisation of vars must be done here.
*/
BOOL MySerial::InitInstance()
{
    m_bAutoDelete = FALSE;
    init = TRUE;
    return TRUE;
}

//! At close thread
int MySerial::ExitInstance()
{
    //TRACE("Close thread.\n");
    return CWinThread::ExitInstance();
}

BEGIN_MESSAGE_MAP(MySerial, CWinThread)
    //{{AFX_MSG_MAP(MySerial)
        // NOTE - the ClassWizard will add and remove mapping macros here.
        ON_THREAD_MESSAGE( WM_MYSERIAL_WRITE, OnWriteData )
        ON_THREAD_MESSAGE( WM_MYSERIAL_CLOSE, closePort )
    //}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// MySerial message handlers

BOOL MySerial::OnIdle(LONG lCount)
{
    // TRACE("Nothing to do.\n");
    return CWinThread::OnIdle(lCount);
}

int MySerial::Run()
{
    //TRACE("Running.");
    return CWinThread::Run();
}

// Message Handler that sends data
// wParam: std::vector<unsigned char>
/*! \brief Writes data into serial comm
    \param wParam: must be a std::vector<unsigned char> with every byte
to send.
    \param lParam: Not used, but must be in definition.
*/
void MySerial::OnWriteData( WPARAM wParam, LPARAM lParam )
{
    //TRACE("Write Exec\n");
    DWORD bytesWritten;
    unsigned char* buffer = (unsigned char*)wParam;

    BOOL ok = ::WriteFile( hComm, buffer, lParam, &bytesWritten,
&ovWriter );
    if( !ok )
    {
        //Fail
        DWORD err = ::GetLastError();
        if( err!=ERROR_IO_PENDING ) //Error grave
        {
            //Tell GUI that an error occourred
            err = ::GetLastError();
            TRACE("Error WriteFile::%d.\n",err);
            delete buffer;
            PostQuitMessage(0);
            return;
        }

        //ERROR_IO_PENDING
        HANDLE waiters[2];
        waiters[0] = ShutdownEvent;
        waiters[1] = WriteEvent;
        DWORD what = ::WaitForMultipleObjects( 2, waiters, FALSE,
INFINITE );
        switch( what )
        {
            case WAIT_OBJECT_0: //Shutdown event
                //Tell GUI that the thread has stopped
                err = ::GetLastError();
                TRACE("Error Wait4Multiple Objects:%d\n",err );
                delete buffer;
                PostQuitMessage(0);
                return;

            case WAIT_OBJECT_0 + 1: //Write completed
                ok = ::GetOverlappedResult( hComm, &ovWriter, &bytesWritten,
TRUE );
                if( !ok )
                { //Fail!
                    //Tell GUI fail occourred
                    TRACE("Fail GeTOverlapped.\n");
                    delete buffer;
                    PostQuitMessage(0);
                    return;
                }
                else
                {
                    //Write complete
                    //Tell GUI that all writed ok
                    //TRACE("Writed with delay.\n");
                    notificador->PostMessage(UWM_MYSERIAL_DATA_WRITTED );
                }
                break;

            default:
                DWORD err = ::GetLastError();
                ASSERT( FALSE );
                TRACE("Fail default.\n");
                delete buffer;
                PostQuitMessage(0);
                return;
        }
    }
    else
    {
        SetEvent( WriterStoped );

        notificador->PostMessage(UWM_MYSERIAL_DATA_WRITTED );
        ResetEvent( WriterStoped );
    }

    delete buffer; //Kill buffer
}

//LRESULT MySerial::ReaderThread(LPVOID cT )
/*! \brief Reads from serial comm port

    This is a thread that continuosly is reading from serial comm
port.<br>
    At every bunch of bytes received, posts a message to main GUI thread
sending the values found.
*/
UINT ReaderThread( LPVOID cT )
{
    MySerial* SerialHandler = (MySerial*)cT;

    BOOL reading = TRUE;
    DWORD bytesRead;
    DWORD shutdown;

    HANDLE waiters[2];
    waiters[0] = SerialHandler->ShutdownEvent;
    waiters[1] = SerialHandler->ovReader.hEvent;

    while( reading )
    {
        unsigned char buffer[MAX_BUFFER_SIZE_MYSERIAL];
        BOOL ok = ::ReadFile( SerialHandler->hComm, buffer,
MAX_BUFFER_SIZE_MYSERIAL, &bytesRead, &SerialHandler->ovReader );
        if( !ok )
        {
            DWORD error = ::GetLastError();
            if( error!= ERROR_IO_PENDING )
            {
                TRACE("ERROR READING.\n");
                shutdown = error; //Store the error
                reading = FALSE; //Stop reading
                continue;
            }

            //ERROR_IO_PENDING
            DWORD result = ::WaitForMultipleObjects( 2, waiters, FALSE,
INFINITE );
            switch( result )
            {
                case WAIT_OBJECT_0: //Event shutdown
                    shutdown = 0;
                    reading = FALSE; //Stop the reading
                    continue;

                case WAIT_OBJECT_0 + 1:
                    ok = ::GetOverlappedResult( SerialHandler->hComm, &SerialHandler-
ovReader, &bytesRead, TRUE ); //Get results
                    
if( !ok )
                    { //GetOverlappedResult has failed
                        shutdown = ::GetLastError();
                        reading = FALSE; //Stop the reading
                        TRACE("ERROR READING\n");
                        continue;
                    }
                    else
                    {
                        //TRACE("READED OK\n");
                    }
                    break;

                default:
                    TRACE("ASSERT\n");
                    shutdown = ::GetLastError();
                    ASSERT(FALSE); //Fallo
                    reading = FALSE;
                    continue;
            }
        }

        if( bytesRead>0 )
        {
            unsigned char* buffer2 = new unsigned
char[MAX_BUFFER_SIZE_MYSERIAL];
            for( int i=(bytesRead-1); i>=0; i-- )
                buffer2[i] = buffer[i];
            SerialHandler->notificador->PostMessage( UWM_MYSERIAL_DATA_READ,
(WPARAM)buffer2, (LPARAM)bytesRead );
        }
        else
        {
            //TRACE("None byte received\n");
        }
    }

    if( shutdown!=0 )
    { SerialHandler->notificador-
PostMessage( UWM_MYSERIAL_ERROR,shutdown, READING );
    
}

    SetEvent( SerialHandler->ReaderStoped );
    return 0;
}

//! \return MySerial::opened
BOOL MySerial::isOpen()
{
    return opened;
}

//! \return MySerial::init
BOOL MySerial::isInit()
{
    return init;
}

//! Stores a pointer to CWnd object in order to be able to send
messages to it.
void MySerial::configure( CWnd* w )
{
    this->notificador = w;
}

/*! \brief Opens port

    Configures MySerial:dcb object and opens port.
*/
BOOL MySerial::openPort( int port )
{
    opened = TRUE;

    WriteEvent = CreateEvent( NULL, TRUE, FALSE, NULL );
    ReadEvent = CreateEvent( NULL, TRUE, FALSE, NULL );
    ReaderStoped = CreateEvent( NULL, TRUE, FALSE, NULL );
    WriterStoped = CreateEvent( NULL, TRUE, FALSE, NULL );

    ShutdownEvent = CreateEvent( NULL, TRUE, FALSE, NULL );

    memset( &ovReader, 0, sizeof( OVERLAPPED ) );
    memset( &ovWriter, 0, sizeof( OVERLAPPED ) );
    ovReader.hEvent = ReadEvent;
    ovWriter.hEvent = WriteEvent;

    CString Sport;
    Sport.Format( "\\\\.\\COM%d",port );

    hComm = CreateFile( Sport, GENERIC_READ | GENERIC_WRITE, 0, NULL,
OPEN_EXISTING, FILE_FLAG_OVERLAPPED, NULL );
    if( hComm == INVALID_HANDLE_VALUE )
    {
        TRACE("Could not open the port.\n");
        opened = FALSE;
        return FALSE;
    }

    BOOL fSucces = GetCommState( hComm, &dcb );
    if( !fSucces )
    {
        TRACE("Error checking port configuration.\n");
        opened = FALSE;
        return FALSE;
    }

    dcb.DCBlength = sizeof(dcb);
    dcb.BaudRate = CBR_57600;
    dcb.fBinary = TRUE;
    dcb.fParity = FALSE;
    dcb.fOutxCtsFlow = FALSE;
    dcb.fOutxDsrFlow = FALSE;
    dcb.fDtrControl = DTR_CONTROL_ENABLE;
    dcb.fDsrSensitivity = FALSE;
    dcb.fTXContinueOnXoff = FALSE;
    dcb.fOutX = FALSE;
    dcb.fInX = FALSE;
    dcb.fErrorChar = 0;
    dcb.fNull = FALSE;
    dcb.fRtsControl = RTS_CONTROL_ENABLE;
    dcb.fAbortOnError = FALSE;
    dcb.XonLim = 2048;
    dcb.XoffLim = 512;
    dcb.ByteSize = 8;
    dcb.Parity = NOPARITY;
    dcb.StopBits = 0; //ONESTOPBIT;
    dcb.XonChar = 17;
    dcb.XoffChar = 19;
    dcb.ErrorChar = 0;
    dcb.EofChar = 0;
    dcb.EvtChar = 0;

    fSucces = SetCommState( hComm, &dcb );

    if( !fSucces )
    {
        TRACE("Error configuring port\n");
        opened = FALSE;
        return FALSE;
    }

    fSucces = PurgeComm( hComm, PURGE_RXABORT|PURGE_RXCLEAR );
    if( !fSucces )
    {
        TRACE("Fail purging port.\n");
        opened = FALSE;
        return FALSE;
    }

    COMMTIMEOUTS timeouts;
    GetCommTimeouts( hComm, &timeouts );

    timeouts.ReadIntervalTimeout = 10;
    timeouts.ReadTotalTimeoutMultiplier = 1;
    timeouts.ReadTotalTimeoutConstant = 10;
    timeouts.WriteTotalTimeoutMultiplier = 0;
    timeouts.WriteTotalTimeoutConstant = 0;

    SetCommTimeouts( hComm, &timeouts );

    //Start the reading
    pReaderThread = AfxBeginThread( ReaderThread, this,
THREAD_PRIORITY_ABOVE_NORMAL );

    return TRUE;
}

/*! \brief Closes port.

    Closes the port opened and Reader thread too.
*/
void MySerial::closePort( WPARAM wparam, LPARAM lparam)
{
    if( opened )
    {
        SetEvent( ShutdownEvent );
        WaitForSingleObject( pReaderThread->m_hThread, INFINITE );

        BOOL ok = PurgeComm( hComm, PURGE_RXABORT|PURGE_RXCLEAR );

        ::CloseHandle( WriteEvent );
        ::CloseHandle( ShutdownEvent );
        ::CloseHandle( ReadEvent );
        ::CloseHandle( hComm );

        PostQuitMessage(0);
        opened = FALSE;
    }
    else
    {
        PostQuitMessage(0);
    }

}

void MySerial::Kill()
{
    opened = FALSE;
    init = FALSE;
}

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