A communication class for serial port

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In the newgroups there are many questions about serial communication so I thought:
make it public! It’s freeware. The only thing I expect from users is that they drop me a mail.
All modifications on this class are free, but please let me know if it solves a bug
or adds some good features. Also comment your code and don’t let me solve your bugs!

Target:

From the classes included there is only one class important: CSerialPort.
The other classes are only there to illustrate the use of this class.

Usage:

// the owner (CWnd) of the port (receives message)

BOOL CSerialPort::InitPort(CWnd* pPortOwner,

 UINT  portnr,   // portnumber (1..4)

 UINT  baud,    // baudrate

 char  parity,   // parity 

 UINT  databits,   // databits 

 UINT  stopbits,   // stopbits 

 DWORD dwCommEvents,  // EV_RXCHAR, EV_CTS etc

 UINT  writebuffersize) // size of the writebuffer

The dwCommEvents flag can be used for communication with the owner of this class.

The flags can be one of the following (or combined with |):

• WM_COMM_BREAK_DETECTED A break was detected on input.


• WM_COMM_CTS_DETECTED The CTS (clear-to-send) signal changed state.


• WM_COMM_DSR_DETECTED The DSR (data-set-ready) signal changed state.


• WM_COMM_ERR_DETECTED A line-status error occurred. Line-status errors are CE_FRAME, CE_OVERRUN, and CE_RXPARITY.


• WM_COMM_RING_DETECTED A ring indicator was detected.


• WM_COMM_RLSD_DETECTED The RLSD (receive-line-signal-detect) signal changed state.


• WM_COMM_RXCHAR A character was received and placed in the input buffer.


• WM_COMM_RXFLAG_DETECTED The event character was received and placed in the input buffer.

Accept the first parameter all parameters are optional. The standard values are:

portnr  = 1

baud  = 19200

parity  = ‘N’

databits  = 8,

stopsbits = 1,

dwCommEvents = EV_RXCHAR | EV_CTS,

nBufferSize = 512);

So the follwing code is enough to make communication possible:

in the header of the owner:

 CSerialPort m_Serial;

in the code:

 m_Serial.InitPort(this);

 m_Serial.StartMonitoring();

Then the tread that watches the port is started and all events on the port are send to
the owner. The receive a character the owner needs a messageentry in the messagemap:

BEGIN_MESSAGE_MAP(CCommtestDlg, CDialog)

 //{{AFX_MSG_MAP(CCommtestDlg)

 ON_MESSAGE(WM_COMM_RXCHAR, OnCommunication)

 ON_MESSAGE(WM_COMM_CTS_DETECTED, OnCTSDetected)

 //}}AFX_MSG_MAP

END_MESSAGE_MAP()

and they must be handled:

LONG CCommtestDlg::OnCommunication(WPARAM ch, LPARAM port)

{

 // do something with the received character

 return 0;

}

This is it for reading. Writing can be done with WriteChar or WriteToPort

Downloads

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