win_qextserialport.cpp

Visual C++串口通信开发入门与编程实践

*/
qint64 Win_QextSerialPort::readData(char *data, qint64 maxSize)
{
    DWORD retVal;
	
    LOCK_MUTEX();
    
    retVal = 0;
	if (queryMode() == QextSerialBase::EventDriven) {
		OVERLAPPED overlapRead;
		overlapRead.Internal = 0;
		overlapRead.InternalHigh = 0;
		overlapRead.Offset = 0;
		overlapRead.OffsetHigh = 0;
		overlapRead.hEvent = CreateEvent(NULL, true, false, NULL);
		if (!ReadFile(Win_Handle, (void*)data, (DWORD)maxSize, & retVal, & overlapRead)) {
			if (GetLastError() == ERROR_IO_PENDING)
				GetOverlappedResult(Win_Handle, & overlapRead, & retVal, true);
			else {
	        	lastErr = E_READ_FAILED;
	        	retVal = (DWORD)-1;
			}
		}
		CloseHandle(overlapRead.hEvent);
	} else if (!ReadFile(Win_Handle, (void*)data, (DWORD)maxSize, & retVal, NULL)) {
        lastErr = E_READ_FAILED;
        retVal = (DWORD)-1;
    }

	UNLOCK_MUTEX();

    return (qint64)retVal;
}

/*!
\fn qint64 Win_QextSerialPort::writeData(const char *data, qint64 maxSize)
Writes a block of data to the serial port.  This function will write len bytes
from the buffer pointed to by data to the serial port.  Return value is the number
of bytes actually written, or -1 on error.

\warning before calling this function ensure that serial port associated with this class
is currently open (use isOpen() function to check if port is open).
*/
qint64 Win_QextSerialPort::writeData(const char *data, qint64 maxSize)
{
	DWORD retVal;
	
    LOCK_MUTEX();

    retVal = 0;
    if (queryMode() == QextSerialBase::EventDriven) {
    	bytesToWriteLock->lockForWrite();
    	_bytesToWrite += maxSize;
    	bytesToWriteLock->unlock();
		overlapWrite.Internal = 0;
		overlapWrite.InternalHigh = 0;
		overlapWrite.Offset = 0;
		overlapWrite.OffsetHigh = 0;
		overlapWrite.hEvent = CreateEvent(NULL, true, false, NULL);
		if (!WriteFile(Win_Handle, (void*)data, (DWORD)maxSize, & retVal, & overlapWrite)) {
			lastErr = E_WRITE_FAILED;
			retVal = (DWORD)-1;
	   	} else
	   		retVal = maxSize;
    } else if (!WriteFile(Win_Handle, (void*)data, (DWORD)maxSize, & retVal, NULL)) {
		lastErr = E_WRITE_FAILED;
		retVal = (DWORD)-1;
   	}
   	
    UNLOCK_MUTEX();

    return (qint64)retVal;
}

/*!
\fn void Win_QextSerialPort::ungetChar(char c)
This function is included to implement the full QIODevice interface, and currently has no
purpose within this class.  This function is meaningless on an unbuffered device and currently
only prints a warning message to that effect.
*/
void Win_QextSerialPort::ungetChar(char c) {

    /*meaningless on unbuffered sequential device - return error and print a warning*/
    TTY_WARNING("Win_QextSerialPort: ungetChar() called on an unbuffered sequential device - operation is meaningless");
}

/*!
\fn void Win_QextSerialPort::setFlowControl(FlowType flow)
Sets the flow control used by the port.  Possible values of flow are:
\verbatim
    FLOW_OFF            No flow control
    FLOW_HARDWARE       Hardware (RTS/CTS) flow control
    FLOW_XONXOFF        Software (XON/XOFF) flow control
\endverbatim
*/
void Win_QextSerialPort::setFlowControl(FlowType flow) {
    LOCK_MUTEX();
    if (Settings.FlowControl!=flow) {
        Settings.FlowControl=flow;
    }
    if (isOpen()) {
        switch(flow) {

            /*no flow control*/
            case FLOW_OFF:
                Win_CommConfig.dcb.fOutxCtsFlow=FALSE;
                Win_CommConfig.dcb.fRtsControl=RTS_CONTROL_DISABLE;
                Win_CommConfig.dcb.fInX=FALSE;
                Win_CommConfig.dcb.fOutX=FALSE;
                SetCommConfig(Win_Handle, &Win_CommConfig, sizeof(COMMCONFIG));
                break;

            /*software (XON/XOFF) flow control*/
            case FLOW_XONXOFF:
                Win_CommConfig.dcb.fOutxCtsFlow=FALSE;
                Win_CommConfig.dcb.fRtsControl=RTS_CONTROL_DISABLE;
                Win_CommConfig.dcb.fInX=TRUE;
                Win_CommConfig.dcb.fOutX=TRUE;
                SetCommConfig(Win_Handle, &Win_CommConfig, sizeof(COMMCONFIG));
                break;

            case FLOW_HARDWARE:
                Win_CommConfig.dcb.fOutxCtsFlow=TRUE;
                Win_CommConfig.dcb.fRtsControl=RTS_CONTROL_HANDSHAKE;
                Win_CommConfig.dcb.fInX=FALSE;
                Win_CommConfig.dcb.fOutX=FALSE;
                SetCommConfig(Win_Handle, &Win_CommConfig, sizeof(COMMCONFIG));
                break;
        }
    }
    UNLOCK_MUTEX();
}

/*!
\fn void Win_QextSerialPort::setParity(ParityType parity)
Sets the parity associated with the serial port.  The possible values of parity are:
\verbatim
    PAR_SPACE       Space Parity
    PAR_MARK        Mark Parity
    PAR_NONE        No Parity
    PAR_EVEN        Even Parity
    PAR_ODD         Odd Parity
\endverbatim
*/
void Win_QextSerialPort::setParity(ParityType parity) {
    LOCK_MUTEX();
    if (Settings.Parity!=parity) {
        Settings.Parity=parity;
    }
    if (isOpen()) {
        Win_CommConfig.dcb.Parity=(unsigned char)parity;
        switch (parity) {

            /*space parity*/
            case PAR_SPACE:
                if (Settings.DataBits==DATA_8) {
                    TTY_PORTABILITY_WARNING("Win_QextSerialPort Portability Warning: Space parity with 8 data bits is not supported by POSIX systems.");
                }
                Win_CommConfig.dcb.fParity=TRUE;
                break;

            /*mark parity - WINDOWS ONLY*/
            case PAR_MARK:
                TTY_PORTABILITY_WARNING("Win_QextSerialPort Portability Warning:  Mark parity is not supported by POSIX systems");
                Win_CommConfig.dcb.fParity=TRUE;
                break;

            /*no parity*/
            case PAR_NONE:
                Win_CommConfig.dcb.fParity=FALSE;
                break;

            /*even parity*/
            case PAR_EVEN:
                Win_CommConfig.dcb.fParity=TRUE;
                break;

            /*odd parity*/
            case PAR_ODD:
                Win_CommConfig.dcb.fParity=TRUE;
                break;
        }
        SetCommConfig(Win_Handle, &Win_CommConfig, sizeof(COMMCONFIG));
    }
    UNLOCK_MUTEX();
}

/*!
\fn void Win_QextSerialPort::setDataBits(DataBitsType dataBits)
Sets the number of data bits used by the serial port.  Possible values of dataBits are:
\verbatim
    DATA_5      5 data bits
    DATA_6      6 data bits
    DATA_7      7 data bits
    DATA_8      8 data bits
\endverbatim

\note
This function is subject to the following restrictions:
\par
    5 data bits cannot be used with 2 stop bits.
\par
    1.5 stop bits can only be used with 5 data bits.
\par
    8 data bits cannot be used with space parity on POSIX systems.

*/
void Win_QextSerialPort::setDataBits(DataBitsType dataBits) {
    LOCK_MUTEX();
    if (Settings.DataBits!=dataBits) {
        if ((Settings.StopBits==STOP_2 && dataBits==DATA_5) ||
            (Settings.StopBits==STOP_1_5 && dataBits!=DATA_5)) {
        }
        else {
            Settings.DataBits=dataBits;
        }
    }
    if (isOpen()) {
        switch(dataBits) {

            /*5 data bits*/
            case DATA_5:
                if (Settings.StopBits==STOP_2) {
                    TTY_WARNING("Win_QextSerialPort: 5 Data bits cannot be used with 2 stop bits.");
                }
                else {
                    Win_CommConfig.dcb.ByteSize=5;
                    SetCommConfig(Win_Handle, &Win_CommConfig, sizeof(COMMCONFIG));
                }
                break;

            /*6 data bits*/
            case DATA_6:
                if (Settings.StopBits==STOP_1_5) {
                    TTY_WARNING("Win_QextSerialPort: 6 Data bits cannot be used with 1.5 stop bits.");
                }
                else {
                    Win_CommConfig.dcb.ByteSize=6;
                    SetCommConfig(Win_Handle, &Win_CommConfig, sizeof(COMMCONFIG));
                }
                break;

            /*7 data bits*/
            case DATA_7:
                if (Settings.StopBits==STOP_1_5) {
                    TTY_WARNING("Win_QextSerialPort: 7 Data bits cannot be used with 1.5 stop bits.");
                }
                else {
                    Win_CommConfig.dcb.ByteSize=7;
                    SetCommConfig(Win_Handle, &Win_CommConfig, sizeof(COMMCONFIG));
                }
                break;

            /*8 data bits*/
            case DATA_8:
                if (Settings.StopBits==STOP_1_5) {
                    TTY_WARNING("Win_QextSerialPort: 8 Data bits cannot be used with 1.5 stop bits.");
                }
                else {
                    Win_CommConfig.dcb.ByteSize=8;
                    SetCommConfig(Win_Handle, &Win_CommConfig, sizeof(COMMCONFIG));
                }
                break;
        }
    }
    UNLOCK_MUTEX();
}

/*!
\fn void Win_QextSerialPort::setStopBits(StopBitsType stopBits)
Sets the number of stop bits used by the serial port.  Possible values of stopBits are:
\verbatim
    STOP_1      1 stop bit
    STOP_1_5    1.5 stop bits
    STOP_2      2 stop bits
\endverbatim

\note
This function is subject to the following restrictions:
\par
    2 stop bits cannot be used with 5 data bits.
\par
    1.5 stop bits cannot be used with 6 or more data bits.
\par
    POSIX does not support 1.5 stop bits.
*/
void Win_QextSerialPort::setStopBits(StopBitsType stopBits) {
    LOCK_MUTEX();
    if (Settings.StopBits!=stopBits) {
        if ((Settings.DataBits==DATA_5 && stopBits==STOP_2) ||
            (stopBits==STOP_1_5 && Settings.DataBits!=DATA_5)) {
        }
        else {
            Settings.StopBits=stopBits;
        }
    }
    if (isOpen()) {
        switch (stopBits) {

            /*one stop bit*/
            case STOP_1:
                Win_CommConfig.dcb.StopBits=ONESTOPBIT;
                SetCommConfig(Win_Handle, &Win_CommConfig, sizeof(COMMCONFIG));
                break;

            /*1.5 stop bits*/
            case STOP_1_5:
                TTY_PORTABILITY_WARNING("Win_QextSerialPort Portability Warning: 1.5 stop bit operation is not supported by POSIX.");
                if (Settings.DataBits!=DATA_5) {
                    TTY_WARNING("Win_QextSerialPort: 1.5 stop bits can only be used with 5 data bits");
                }
                else {
                    Win_CommConfig.dcb.StopBits=ONE5STOPBITS;
                    SetCommConfig(Win_Handle, &Win_CommConfig, sizeof(COMMCONFIG));
                }
                break;

            /*two stop bits*/
            case STOP_2:
                if (Settings.DataBits==DATA_5) {
                    TTY_WARNING("Win_QextSerialPort: 2 stop bits cannot be used with 5 data bits");
                }
                else {
                    Win_CommConfig.dcb.StopBits=TWOSTOPBITS;
                    SetCommConfig(Win_Handle, &Win_CommConfig, sizeof(COMMCONFIG));
                }
                break;
        }
    }
    UNLOCK_MUTEX();
}

/*!
\fn void Win_QextSerialPort::setBaudRate(BaudRateType baudRate)
Sets the baud rate of the serial port.  Note that not all rates are applicable on
all platforms.  The following table shows translations of the various baud rate
constants on Windows(including NT/2000) and POSIX platforms.  Speeds marked with an *
are speeds that are usable on both Windows and POSIX.
\verbatim

  RATE          Windows Speed   POSIX Speed
  -----------   -------------   -----------
   BAUD50                 110          50
   BAUD75                 110          75
  *BAUD110                110         110
   BAUD134                110         134.5
   BAUD150                110         150
   BAUD200                110         200
  *BAUD300                300         300
  *BAUD600                600         600