Welcome to CSerialPort / CSerialPort2, two freeware C++ classes to wrap access to the Win32 APIs dealing with serial ports.
Features |
Usage |
Copyright |
History |
API Reference |
Contacting the Author |
v1.34 (17 December 2017)
v1.33 (16 August 2017)
v1.32 (22 May 2016)
v1.31 (17 December 2015)
v1.30 (26 April 2015)
v1.29 (28 February 2015)
v1.28 (25 January 2013)
v1.27 (4 July 2008)
v1.26 (21 June 2008)
v1.25 (18 May 2008)
v1.24 (30 December 2007)
v1.23 (24 December 2007)
v1.22 (25 January 2007)
v1.21 (5 November 2006)
v1.20 (25 June 2006)
v1.19 (24 June 2006)
v1.18 (5 June 2006)
v1.17 (2 June 2006)
v1.16 (10 April 2006)
5 March 2003
V1.15 (20 September 2002)
V1.14 (7 August 2002)
V1.13 (29 May 2002)
V1.12 (1 May 2002)
V1.11 (23 April 2001)
V1.10 (4 April 2001)
V1.09 (24 March 2001)
V1.08 (15 January 2001)
V1.07 (10 December 2000)
3 July 2000
V1.06 (12 June 2000)
V1.05 (8 May 2000)
V1.04 (8 March 2000)
V1.03 (29 September 1999)
V1.02 (16 June 1999)
V1.01 (3 June 1999)
V1.0 (31 May 1999)
The API consists of the classes: CSerialException, CSerialPort and the non exception based CSerialPort2. The CSerialException and CSerialPort classes have the following member functions and variables:
CSerialException::CSerialException
CSerialException::GetErrorMessage
CSerialException::m_dwError
CSerialPort::CSerialPort
CSerialPort::~CSerialPort
CSerialPort::Open
CSerialPort::Close
CSerialPort::Attach
CSerialPort::Detach
CSerialPort::operator
HANDLE
CSerialPort::IsOpen
CSerialPort::Dump
CSerialPort::Read
CSerialPort::ReadEx
CSerialPort::Write
CSerialPort::WriteEx
CSerialPort::TransmitChar
CSerialPort::GetOverlappedResult
CSerialPort::CancelIo
CSerialPort::CancelIoEx
CSerialPort::GetConfig
CSerialPort::GetDefaultConfig
CSerialPort::SetConfig
CSerialPort::SetDefaultConfig
CSerialPort::ClearBreak
CSerialPort::SetBreak
CSerialPort::ClearError
CSerialPort::GetStatus
CSerialPort::GetState
CSerialPort::SetState
CSerialPort::Escape
CSerialPort::ClearDTR
CSerialPort::ClearRTS
CSerialPort::SetDTR
CSerialPort::SetRTS
CSerialPort::SetXOFF
CSerialPort::SetXON
CSerialPort::GetProperties
CSerialPort::GetModemStatus
CSerialPort::SetTimeouts
CSerialPort::GetTimeouts
CSerialPort::Set0Timeout
CSerialPort::Set0WriteTimeout
CSerialPort::Set0ReadTimeout
CSerialPort::SetMask
CSerialPort::GetMask
CSerialPort::WaitEvent
CSerialPort::Flush
CSerialPort::Purge
CSerialPort::TerminateOutstandingWrites
CSerialPort::TerminateOutstandingReads
CSerialPort::ClearWriteBuffer
CSerialPort::ClearReadBuffer
CSerialPort::Setup
CSerialPort::BytesWaiting
CSerialException::CSerialException
CSerialException(DWORD dwError = 0);
Parameters
dwError The error that caused the exception.
Remarks
This member function is called when a CSerialException object is created. To throw a CSerialException, call the method CSerialPort::ThrowSerialException. If you call if using the default value for dwError, then internally it will call GetLastError for you.
CSerialException::GetErrorMessage
virtual BOOL GetErrorMessage(LPTSTR lpszError, UINT nMaxError,
PUINT pnHelpContext = nullptr);
CString GetErrorMessage();
Return Value
1) Nonzero if the function is successful; otherwise 0 if no error message text is available.
2) A CString representation of the error
Parameters
lpszError A pointer to a buffer that will receive an error message.
nMaxError The maximum number of characters the buffer can hold, including the null terminator.
pnHelpContext The address of a UINT that will receive the help context ID. If null, no ID will be returned.
Remarks
Call this member function to provide text about an error that has occurred. Note this method is only available if you enable MFC integration via CSERIALPORT_MFC_EXTENSIONS.
Remarks
The error that caused the exception. This error value is a system error code as found in WinError.h.
For a list of Win32 error codes, see Error Codes in the Win32 SDK.
CSerialPort();
Remarks
Standard C++ constructor for the class. Internally it just sets up the member variables to default values.
virtual ~CSerialPort();
Remarks
Standard C++ destructor for the class. It will ensure that the comm port is closed if it is open.
void Open(LPCTSTR pszPort, BOOL bOverlapped = FALSE);
void Open(LPCTSTR
pszPort, DWORD dwBaud = 9600,
Parity parity = NoParity, BYTE DataBits
= 8, StopBits stopBits = OneStopBit, FlowControl
fc = NoFlowControl, BOOL bOverlapped = FALSE);
void Open(int
nPort, DWORD dwBaud = 9600, Parity parity
= NoParity, BYTE DataBits = 8, StopBits stopBits
= OneStopBit, FlowControl fc = NoFlowControl, BOOL
bOverlapped = FALSE);
throw( CSerialException* /
CSerialException& );
Parameters
nPort The communications port to open.
pszPort The name of the communications port to open. Note you would use this version of the Open method if the serial port does not have a name of type "COM%d".
dwBaud The baud rate to use
parity The parity to use. parity is an enum with the following values:
enum Parity
{
EvenParity,
MarkParity,
NoParity,
OddParity,
SpaceParity
};
Databits The number of data bits to use
stopbits The number of stop bits to use. stopbits is an enum with the following values:
enum StopBits
{
OneStopBit,
OnePointFiveStopBits,
TwoStopBits
};
fc The flow control method to use. fc is an enum with the following values:
enum FlowControl
{
NoFlowControl,
CtsRtsFlowControl,
CtsDtrFlowControl,
DsrRtsFlowControl,
DsrDtrFlowControl,
XonXoffFlowControl
};
bOverlapped TRUE if you want to open in overlapped mode, otherwise FALSE to use blocking calls.
Remarks
Call this member function to open a communications port. Internally the class will use CreateFile to open the comm port (handling the case where the port number if greater than 9) and then uses SetState to set the various RS-232 settings as specified via the function parameters. If an error occurs, a CSerialException will be thrown.
Close();
Remarks
The corollary function to Open. Just closes the comm port if already open.
void Attach(HANDLE hComm);
Parameters
hComm The SDK handle of the open comm port.
Remarks
Allows you to attach a CSerialPort instance to an existing SDK comm port handle. This function is similar in behaviour to the CWnd::Attach function provided in MFC.
HANDLE Detach();
Return Value
The SDK comm port HANDLE.
Remarks
Corollary function to Attach. This function is similar in behaviour to the CWnd::Detach function provided in MFC.
operator HANDLE();
Return Value
The SDK comm port HANDLE.
Remarks
Use this operator to get the handle of the underlying comm port. You can use this handle to call the Windows APIs directly.
BOOL IsOpen() const
Return Value
TRUE if the comm port is open otherwise FALSE
void Dump(CDumpContext& dc) const
Remarks
Standard MFC diagnostic support function
DWORD Read(void* lpBuffer, DWORD dwNumberOfBytesToRead);
void Read(void* lpBuffer, DWORD dwCount, OVERLAPPED&
overlapped, DWORD* lpNumberOfBytesRead
= nullptr);
void ReadEx(void* lpBuffer, DWORD dwNumberOfBytesToRead,
LPOVERLAPPED lpOverlapped, LPOVERLAPPED_COMPLETION_ROUTINE
lpCompletionRoutine);
throw( CSerialException*/
CSerialException& );
Return Value
1) The number of bytes read.
2) & 3) No return value
Parameters
lpBuffer Points to the buffer to read the data into from the serial port
dwNumberOfBytesToRead Specifies the number of bytes to read from the serial port.
overlapped reference to an OVERLAPPED structure. This is required if the port was opened in overlapped mode.
lpNumberOfBytesRead If the value is non-null then upon return it will contain the number of bytes read
lpOverlapped pointer to the OVERLAPPEDpped structure to use
lpCompletionRoutine the completion routine to use
Remarks
These 3 functions are wrappers for the SDK calls ReadFile and ReadFileEx. Also please note that depending on the way you have configured timeouts, this function may appear to block while it waits to receive the specified data. To configure timeouts, please check out the Set*Timeout(s) functions.
DWORD Write(const void* lpBuffer, DWORD dwNumberOfBytesToWrite);
void Write(const void* lpBuffer, DWORD dwNumberOfBytesToWrite,
OVERLAPPED& overlapped, DWORD* lpNumberOfBytesWritten
= nullptr);
void WriteEx(const void* lpBuffer, DWORD
dwNumberOfBytesToWrite, LPOVERLAPPED lpOverlapped,
LPOVERLAPPED_COMPLETION_ROUTINE lpCompletionRoutine);
throw( CSerialException* / CSerialException& );
Return Value
1) The number of bytes written.
2) & 3) No return value
Parameters
lpBuffer Points to the buffer containing the data to be written to the serial port
dwNumberOfBytesToWrite Specifies the number of bytes to write to the serial port.
overlapped reference to an OVERLAPPED structure. This is required if the port was opened in overlapped mode.
lpNumberOfBytesWritten If the value is non-null then upon return it will contain the number of bytes written
lpOverlapped pointer to the OVERLAPPEDpped structure to use
lpCompletionRoutine the completion routine to use
Remarks
These 3 functions are wrappers for the SDK calls WriteFile and WriteFileEx.
void TransmitChar(char cChar) const
throw( CSerialException*/ CSerialException& );
Remarks
Simple wrapper for the TransmitCommChar SDK function call. See the Win32 SDK documentation for further details.
CSerialPort::GetOverlappedResult
void GetOverlappedResult(OVERLAPPED& overlapped, DWORD&
dwBytesTransferred, BOOL bWait)
throw( CSerialException* / CSerialException& );
Remarks
Simple wrapper for the GetOverlappedResult SDK function call. See the Win32 SDK documentation for further details.
void CancelIo()
throw( CSerialException* /
CSerialException& );
Remarks
Simple wrapper for the CancelIo SDK function call. See the Win32 SDK documentation for further details.
void CancelIoEx(_In_opt_ LPOVERLAPPED lpOverlapped = nullptr)
throw( CSerialException*
/ CSerialException& );
Remarks
Simple wrapper for the CancelIoEx SDK function call. See the Win32 SDK documentation for further details.
void GetConfig(COMMCONFIG& config)
throw( CSerialException* / CSerialException& );
Remarks
Simple wrapper for the GetCommConfig SDK function call. See the Win32 SDK documentation for further details.
static void GetDefaultConfig(int nPort, COMMCONFIG&
config)
throw( CSerialException*/ CSerialException&
);
static void GetDefaultConfig(LPCTSTR pszPort, COMMCONFIG&
config)
throw( CSerialException*/ CSerialException&
);
Remarks
Simple wrapper for the GetDefaultCommConfig SDK function call. See the Win32 SDK documentation for further details.
void SetConfig(COMMCONFIG& config)
throw( CSerialException* / CSerialException& );
Remarks
Simple wrapper for the SetCommConfig SDK function call. See the Win32 SDK documentation for further details.
static void SetDefaultConfig(int nPort, COMMCONFIG&
config)
throw( CSerialException* / CSerialException&
);
static void SetDefaultConfig(LPCTSTR pszPort, COMMCONFIG&
config)
throw( CSerialException* / CSerialException&
);
Remarks
Simple wrapper for the SetDefaultCommConfig SDK function call. See the Win32 SDK documentation for further details.
void ClearBreak()
throw( CSerialException* / CSerialException&
);
Remarks
Simple wrapper for the ClearCommBreak SDK function call. See the Win32 SDK documentation for further details.
void SetBreak()
throw( CSerialException* / CSerialException&
);
Remarks
Simple wrapper for the SetCommBreak SDK function call. See the Win32 SDK documentation for further details.
void ClearError(DWORD& dwErrors)
throw( CSerialException*/ CSerialException& );
Remarks
Simple wrapper for the ClearCommError SDK function call. See the Win32 SDK documentation for further details.
void GetStatus(COMMSTAT& stat)
throw( CSerialException* / CSerialException& );
Remarks
Another way of returning information which the SDK call ClearCommError returns. See the Win32 SDK documentation for further details.
void GetState(DCB& dcb)
throw(
CSerialException* / CSerialException& );
Remarks
Simple wrapper for the GetCommState SDK function call. See the Win32 SDK documentation for further details.
void SetState(DCB& dcb)
throw(
CSerialException* / CSerialException& );
Remarks
Simple wrapper for the SetCommState SDK function call. See the Win32 SDK documentation for further details.
void Escape(DWORD dwFunc)
throw(
CSerialException* / CSerialException& );
Remarks
Simple wrapper for the EscapeCommFunction SDK function call. See the Win32 SDK documentation for further details.
void ClearDTR()
throw( CSerialException* / CSerialException&
);
Remarks
Calls the Escape function using the constant CLRDTR which lowers the DTR line.
void ClearRTS()
throw( CSerialException* / CSerialException&
);
Remarks
Calls the Escape function using the constant CLRRTS which lowers the RTS line.
void SetDTR()
throw( CSerialException* / CSerialException&
);
Remarks
Calls the Escape function using the constant SETDTR which raises the DTR line.
void SetRTS()
throw( CSerialException* / CSerialException&
);
Remarks
Calls the Escape function using the constant SETRTS which raises the RTS line.
void SetXOFF()
throw( CSerialException* / CSerialException&
);
Remarks
Calls the Escape function using the constant SETXOFF which causes transmission to act as if an XOFF character has been received.
void SetXON()
throw( CSerialException* / CSerialException&
);
Remarks
Calls the Escape function using the constant SETXON which causes transmission to act as if an XON character has been received.
void GetProperties(COMMPROP& properties)
throw( CSerialException* / CSerialException& );
Remarks
Simple wrapper for the GetCommProperties SDK function call. See the Win32 SDK documentation for further details.
void GetModemStatus(DWORD& dwModemStatus)
throw( CSerialException* / CSerialException& );
Remarks
Simple wrapper for the GetCommModemStatus SDK function call. See the Win32 SDK documentation for further details.
void SetTimeouts(COMMTIMEOUTS& timeouts)
throw( CSerialException* );
Remarks
Simple wrapper for the SetCommTimeouts SDK function call. See the Win32 SDK documentation for further details.
void GetTimeouts(COMMTIMEOUTS& timeouts)
throw( CSerialException* / CSerialException& );
Remarks
Simple wrapper for the GetCommTimeouts SDK function call. See the Win32 SDK documentation for further details.
void Set0Timeout()
throw( CSerialException* / CSerialException&
);
Remarks
Configure both send and receive timeouts to be 0. This cause writes to return immediately and for reads to return with whatever data is waiting in the receive buffer rather than wait for the specified amount of bytes to arrive.
void Set0WriteTimeout()
throw( CSerialException* / CSerialException&
);
Remarks
Configures the send timeouts to be 0. This cause writes to return immediately.
void Set0ReadTimeout()
throw( CSerialException* / CSerialException&
);
Remarks
Configure the receive timeout to be 0. This cause reads to return with whatever data is waiting in the receive buffer rather than wait for the specified amount of bytes to arrive.
void SetMask(DWORD dwMask)
throw(
CSerialException* / CSerialException& );
Remarks
Simple wrapper for the SetCommMask SDK function call. See the Win32 SDK documentation for further details.
void GetMask(DWORD& dwMask)
throw( CSerialException* / CSerialException& );
Remarks
Simple wrapper for the GetCommMask SDK function call. See the Win32 SDK documentation for further details.
void WaitEvent(DWORD& dwMask)
BOOL WaitEvent(DWORD&
dwMask, OVERLAPPED& overlapped)
throw( CSerialException* / CSerialException& );
Return Value
TRUE if the overlapped read completely synchronously, FALSE if the operation is to be completed asynchronously.
Remarks
Simple wrapper for the WaitCommEvent SDK function call. The second version of WaitEvent is the overlapped version which will return immediately and you can wait for the manual reset event member of the OVERLAPPED structure to become signalled in your code. See the Win32 SDK documentation for further details.
void Flush()
throw( CSerialException* / CSerialException&
);
Remarks
Simple wrapper for the FlushFileBuffers SDK function call. See the Win32 SDK documentation for further details.
void Purge(DWORD dwFlags)
throw(
CSerialException* / CSerialException& );
Remarks
Simple wrapper for the PurgeComm SDK function call. See the Win32 SDK documentation for further details.
CSerialPort::TerminateOutstandingWrites
void TerminateOutstandingWrites()
throw( CSerialException*
/ CSerialException& );
Remarks
Calls the Purge function using the constant PURGE_TXABORT which terminates all outstanding write operations and returns immediately, even if the write operations have not been completed.
CSerialPort::TerminateOutstandingReads
void TerminateOutstandingReads()
throw( CSerialException*
/ CSerialException& );
Remarks
Calls the Purge function using the constant PURGE_RXABORT which terminates all outstanding read operations and returns immediately, even if the read operations have not been completed.
void ClearWriteBuffer()
throw( CSerialException* / CSerialException&
);
Remarks
Calls the Purge function using the constant PURGE_TXCLEAR which clears the output buffer (if the device driver has one)..
void ClearReadBuffer()
throw( CSerialException* / CSerialException&
);
Remarks
Calls the Purge function using the constant PURGE_RXCLEAR which clears the input buffer (if the device driver has one)..
void Setup(DWORD dwInQueue, DWORD dwOutQueue)
throw( CSerialException* / CSerialException& );
Remarks
Simple wrapper for the SetupComm SDK function call. See the Win32 SDK documentation for further details.
DWORD BytesWaiting();
throw( CSerialException* / CSerialException&
);
Return Value
The number of bytes waiting to be read from the serial port
Remarks
The function returns the number of bytes waiting to be read from the serial port
PJ Naughter
Email: pjna@naughter.com
Web: http://www.naughter.com
17
December 2017