版权声明：本文为xiaobin原创文章，未经博主允许不得转载。 https://blog.csdn.net/xiaobin_HLJ80/article/details/42848701
这是一个GitHub项目，由xiaobin80来维护。
HTTPS链接： https://github.com/xiaobin80/SerialComm.git
SSH链接： [email protected]:xiaobin80/SerialComm.git
开发语言：VC2010
sln文件： SerialComm.sln
请把此文件放置与“SerialComm”库同一目录。
详见：附录1。
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目前实现的效果如下图:
项目导读：
- 串口读写工具
- CSerialPort --- Remon Spekreijse
- MFC --- VS2010（VC10）
界面分三块：
1. 端口配置
1.1 在“Port Number”选择端口号；
1.2 在“Config”配置端口的属性，比如波特率、奇偶校验、数据位、停止位等等。
2. 发送区域
2.1 Loop Send
当我们钩选此复选框时，必须选择“发送频率”，然后才能执行循环发送数据。
2.2 发送频率
默认500、1000、2000毫秒。
2.3 发送内容框
在“发送信息框”输入内容就可发送数据了！
点击“Send”按钮为手动发送数据。
3. 接收区域
3.1 制式切换
当钩选了“Hex View”复选框，接收到的数据就以16进制显示。
3.2 清除数据
当点击“Clear”按钮，即清空接收框数据。
3.3 数据保存
当点击“Save As”按钮，即保存接收框数据；默认文件格式为rtf文件。
附:
0. GPL2.0
GNU GENERAL PUBLIC LICENSE
Version 2, June 1991
Copyright (C) 1989, 1991 Free Software Foundation, Inc.
59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
Everyone is permitted to copy and distribute verbatim copies
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Public License instead of this License.
1. SerialComm.sln
Microsoft Visual Studio Solution File, Format Version 11.00
# Visual Studio 2010
Project("{8BC9CEB8-8B4A-11D0-8D11-00A0C91BC942}") = "SerialComm", "SerialComm\SerialComm.vcxproj", "{886C559E-5E6B-4EEC-9D3B-FE3433013718}"
EndProject
Global
GlobalSection(SolutionConfigurationPlatforms) = preSolution
Debug|Win32 = Debug|Win32
Release|Win32 = Release|Win32
EndGlobalSection
GlobalSection(ProjectConfigurationPlatforms) = postSolution
{886C559E-5E6B-4EEC-9D3B-FE3433013718}.Debug|Win32.ActiveCfg = Debug|Win32
{886C559E-5E6B-4EEC-9D3B-FE3433013718}.Debug|Win32.Build.0 = Debug|Win32
{886C559E-5E6B-4EEC-9D3B-FE3433013718}.Release|Win32.ActiveCfg = Release|Win32
{886C559E-5E6B-4EEC-9D3B-FE3433013718}.Release|Win32.Build.0 = Release|Win32
EndGlobalSection
GlobalSection(SolutionProperties) = preSolution
HideSolutionNode = FALSE
EndGlobalSection
EndGlobal
2. CSerialPort类
SerialPort.h
/*
** FILENAME CSerialPort.h
**
** PURPOSE This class can read, write and watch one serial port.
** It sends messages to its owner when something happends on the port
** The class creates a thread for reading and writing so the main
** program is not blocked.
**
** CREATION DATE 15-09-1997
** LAST MODIFICATION 12-11-1997
**
** AUTHOR Remon Spekreijse
**
**
*/
#ifndef __SERIALPORT_H__
#define __SERIALPORT_H__
#define WM_COMM_BREAK_DETECTED WM_USER+1 // A break was detected on input.
#define WM_COMM_CTS_DETECTED WM_USER+2 // The CTS (clear-to-send) signal changed state.
#define WM_COMM_DSR_DETECTED WM_USER+3 // The DSR (data-set-ready) signal changed state.
#define WM_COMM_ERR_DETECTED WM_USER+4 // A line-status error occurred. Line-status errors are CE_FRAME, CE_OVERRUN, and CE_RXPARITY.
#define WM_COMM_RING_DETECTED WM_USER+5 // A ring indicator was detected.
#define WM_COMM_RLSD_DETECTED WM_USER+6 // The RLSD (receive-line-signal-detect) signal changed state.
#define WM_COMM_RXCHAR WM_USER+7 // A character was received and placed in the input buffer.
#define WM_COMM_RXFLAG_DETECTED WM_USER+8 // The event character was received and placed in the input buffer.
#define WM_COMM_TXEMPTY_DETECTED WM_USER+9 // The last character in the output buffer was sent.
class CSerialPort
{
public:
// contruction and destruction
CSerialPort();
virtual ~CSerialPort();
// port initialisation
BOOL InitPort(CWnd* pPortOwner, UINT portnr = 1, UINT baud = 19200, char parity = 'N', UINT databits = 8, UINT stopsbits = 1, DWORD dwCommEvents = EV_RXCHAR | EV_CTS, UINT nBufferSize = 512);
// start/stop comm watching
BOOL StartMonitoring();
BOOL RestartMonitoring();
BOOL StopMonitoring();
DWORD GetWriteBufferSize();
DWORD GetCommEvents();
DCB GetDCB();
void WriteToPort(char* string);
protected:
// protected memberfunctions
void ProcessErrorMessage(char* ErrorText);
static UINT CommThread(LPVOID pParam);
static void ReceiveChar(CSerialPort* port, COMSTAT comstat);
static void WriteChar(CSerialPort* port);
// thread
CWinThread* m_Thread;
// synchronisation objects
CRITICAL_SECTION m_csCommunicationSync;
BOOL m_bThreadAlive;
// handles
HANDLE m_hShutdownEvent;
HANDLE m_hComm;
HANDLE m_hWriteEvent;
// Event array.
// One element is used for each event. There are two event handles for each port.
// A Write event and a receive character event which is located in the overlapped structure (m_ov.hEvent).
// There is a general shutdown when the port is closed.
HANDLE m_hEventArray[3];
// structures
OVERLAPPED m_ov;
COMMTIMEOUTS m_CommTimeouts;
DCB m_dcb;
// owner window
CWnd* m_pOwner;
// misc
UINT m_nPortNr;
char* m_szWriteBuffer;
DWORD m_dwCommEvents;
DWORD m_nWriteBufferSize;
};
#endif __SERIALPORT_H__
SerialPort.cpp
/*
** FILENAME CSerialPort.cpp
**
** PURPOSE This class can read, write and watch one serial port.
** It sends messages to its owner when something happends on the port
** The class creates a thread for reading and writing so the main
** program is not blocked.
**
** CREATION DATE 15-09-1997
** LAST MODIFICATION 12-11-1997
**
** AUTHOR Remon Spekreijse
**
**
*/
#include "stdafx.h"
#include "SerialPort.h"
#include <assert.h>
//
// Constructor
//
CSerialPort::CSerialPort()
{
m_hComm = NULL;
// initialize overlapped structure members to zero
m_ov.Offset = 0;
m_ov.OffsetHigh = 0;
// create events
m_ov.hEvent = NULL;
m_hWriteEvent = NULL;
m_hShutdownEvent = NULL;
m_szWriteBuffer = NULL;
m_bThreadAlive = FALSE;
}
//
// Delete dynamic memory
//
CSerialPort::~CSerialPort()
{
do
{
SetEvent(m_hShutdownEvent);
} while (m_bThreadAlive);
TRACE("Thread ended\n");
delete [] m_szWriteBuffer;
}
//
// Initialize the port. This can be port 1 to 99.
//
BOOL CSerialPort::InitPort(CWnd* pPortOwner, // the owner (CWnd) of the port (receives message)
UINT portnr, // portnumber (1..99)
UINT baud, // baudrate
char parity, // parity
UINT databits, // databits
UINT stopbits, // stopbits
DWORD dwCommEvents, // EV_RXCHAR, EV_CTS etc
UINT writebuffersize) // size to the writebuffer
{
assert(portnr > 0 && portnr < 99);
assert(pPortOwner != NULL);
// if the thread is alive: Kill
if (m_bThreadAlive)
{
do
{
SetEvent(m_hShutdownEvent);
} while (m_bThreadAlive);
TRACE("Thread ended\n");
}
// create events
if (m_ov.hEvent != NULL)
ResetEvent(m_ov.hEvent);
m_ov.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
if (m_hWriteEvent != NULL)
ResetEvent(m_hWriteEvent);
m_hWriteEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
if (m_hShutdownEvent != NULL)
ResetEvent(m_hShutdownEvent);
m_hShutdownEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
// initialize the event objects
m_hEventArray[0] = m_hShutdownEvent; // highest priority
m_hEventArray[1] = m_ov.hEvent;
m_hEventArray[2] = m_hWriteEvent;
// initialize critical section
InitializeCriticalSection(&m_csCommunicationSync);
// set buffersize for writing and save the owner
m_pOwner = pPortOwner;
if (m_szWriteBuffer != NULL)
delete [] m_szWriteBuffer;
m_szWriteBuffer = new char[writebuffersize];
m_nPortNr = portnr;
m_nWriteBufferSize = writebuffersize;
m_dwCommEvents = dwCommEvents;
BOOL bResult = FALSE;
char *szPort = new char[50];
char *szBaud = new char[50];
// now it critical!
EnterCriticalSection(&m_csCommunicationSync);
// if the port is already opened: close it
if (m_hComm != NULL)
{
CloseHandle(m_hComm);
m_hComm = NULL;
}
// prepare port strings
sprintf(szPort, "COM%d", portnr);
sprintf(szBaud, "baud=%d parity=%c data=%d stop=%d", baud, parity, databits, stopbits);
// get a handle to the port
m_hComm = CreateFile(szPort, // communication port string (COMX)
GENERIC_READ | GENERIC_WRITE, // read/write types
0, // comm devices must be opened with exclusive access
NULL, // no security attributes
OPEN_EXISTING, // comm devices must use OPEN_EXISTING
FILE_FLAG_OVERLAPPED, // Async I/O
0); // template must be 0 for comm devices
if (m_hComm == INVALID_HANDLE_VALUE)
{
// port not found
delete [] szPort;
delete [] szBaud;
return FALSE;
}
// set the timeout values
m_CommTimeouts.ReadIntervalTimeout = 1000;
m_CommTimeouts.ReadTotalTimeoutMultiplier = 1000;
m_CommTimeouts.ReadTotalTimeoutConstant = 1000;
m_CommTimeouts.WriteTotalTimeoutMultiplier = 1000;
m_CommTimeouts.WriteTotalTimeoutConstant = 1000;
// configure
if (SetCommTimeouts(m_hComm, &m_CommTimeouts))
{
if (SetCommMask(m_hComm, dwCommEvents))
{
if (GetCommState(m_hComm, &m_dcb))
{
m_dcb.fRtsControl = RTS_CONTROL_ENABLE; // set RTS bit high!
if (BuildCommDCB(szBaud, &m_dcb))
{
if (SetCommState(m_hComm, &m_dcb))
; // normal operation... continue
else
ProcessErrorMessage("SetCommState()");
}
else
ProcessErrorMessage("BuildCommDCB()");
}
else
ProcessErrorMessage("GetCommState()");
}
else
ProcessErrorMessage("SetCommMask()");
}
else
ProcessErrorMessage("SetCommTimeouts()");
delete [] szPort;
delete [] szBaud;
// flush the port
PurgeComm(m_hComm, PURGE_RXCLEAR | PURGE_TXCLEAR | PURGE_RXABORT | PURGE_TXABORT);
// release critical section
LeaveCriticalSection(&m_csCommunicationSync);
TRACE("Initialisation for communicationport %d completed.\nUse Startmonitor to communicate.\n", portnr);
return TRUE;
}
//
// The CommThread Function.
//
UINT CSerialPort::CommThread(LPVOID pParam)
{
// Cast the void pointer passed to the thread back to
// a pointer of CSerialPort class
CSerialPort *port = (CSerialPort*)pParam;
// Set the status variable in the dialog class to
// TRUE to indicate the thread is running.
port->m_bThreadAlive = TRUE;
// Misc. variables
DWORD BytesTransfered = 0;
DWORD Event = 0;
DWORD CommEvent = 0;
DWORD dwError = 0;
COMSTAT comstat;
BOOL bResult = TRUE;
// Clear comm buffers at startup
if (port->m_hComm) // check if the port is opened
PurgeComm(port->m_hComm, PURGE_RXCLEAR | PURGE_TXCLEAR | PURGE_RXABORT | PURGE_TXABORT);
// begin forever loop. This loop will run as long as the thread is alive.
for (;;)
{
// Make a call to WaitCommEvent(). This call will return immediatly
// because our port was created as an async port (FILE_FLAG_OVERLAPPED
// and an m_OverlappedStructerlapped structure specified). This call will cause the
// m_OverlappedStructerlapped element m_OverlappedStruct.hEvent, which is part of the m_hEventArray to
// be placed in a non-signeled state if there are no bytes available to be read,
// or to a signeled state if there are bytes available. If this event handle
// is set to the non-signeled state, it will be set to signeled when a
// character arrives at the port.
// we do this for each port!
bResult = WaitCommEvent(port->m_hComm, &Event, &port->m_ov);
if (!bResult)
{
// If WaitCommEvent() returns FALSE, process the last error to determin
// the reason..
switch (dwError = GetLastError())
{
case ERROR_IO_PENDING:
{
// This is a normal return value if there are no bytes
// to read at the port.
// Do nothing and continue
break;
}
case 87:
{
// Under Windows NT, this value is returned for some reason.
// I have not investigated why, but it is also a valid reply
// Also do nothing and continue.
break;
}
default:
{
// All other error codes indicate a serious error has
// occured. Process this error.
port->ProcessErrorMessage("WaitCommEvent()");
break;
}
}
}
else
{
// If WaitCommEvent() returns TRUE, check to be sure there are
// actually bytes in the buffer to read.
//
// If you are reading more than one byte at a time from the buffer
// (which this program does not do) you will have the situation occur
// where the first byte to arrive will cause the WaitForMultipleObjects()
// function to stop waiting. The WaitForMultipleObjects() function
// resets the event handle in m_OverlappedStruct.hEvent to the non-signelead state
// as it returns.
//
// If in the time between the reset of this event and the call to
// ReadFile() more bytes arrive, the m_OverlappedStruct.hEvent handle will be set again
// to the signeled state. When the call to ReadFile() occurs, it will
// read all of the bytes from the buffer, and the program will
// loop back around to WaitCommEvent().
//
// At this point you will be in the situation where m_OverlappedStruct.hEvent is set,
// but there are no bytes available to read. If you proceed and call
// ReadFile(), it will return immediatly due to the async port setup, but
// GetOverlappedResults() will not return until the next character arrives.
//
// It is not desirable for the GetOverlappedResults() function to be in
// this state. The thread shutdown event (event 0) and the WriteFile()
// event (Event2) will not work if the thread is blocked by GetOverlappedResults().
//
// The solution to this is to check the buffer with a call to ClearCommError().
// This call will reset the event handle, and if there are no bytes to read
// we can loop back through WaitCommEvent() again, then proceed.
// If there are really bytes to read, do nothing and proceed.
bResult = ClearCommError(port->m_hComm, &dwError, &comstat);
if (comstat.cbInQue == 0)
continue;
} // end if bResult
// Main wait function. This function will normally block the thread
// until one of nine events occur that require action.
Event = WaitForMultipleObjects(3, port->m_hEventArray, FALSE, INFINITE);
switch (Event)
{
case 0:
{
// Shutdown event. This is event zero so it will be
// the higest priority and be serviced first.
port->m_bThreadAlive = FALSE;
// Kill this thread. break is not needed, but makes me feel better.
AfxEndThread(100);
break;
}
case 1: // read event
{
GetCommMask(port->m_hComm, &CommEvent);
if (CommEvent & EV_CTS)
::SendMessage(port->m_pOwner->m_hWnd, WM_COMM_CTS_DETECTED, (WPARAM) 0, (LPARAM) port->m_nPortNr);
if (CommEvent & EV_RXFLAG)
::SendMessage(port->m_pOwner->m_hWnd, WM_COMM_RXFLAG_DETECTED, (WPARAM) 0, (LPARAM) port->m_nPortNr);
if (CommEvent & EV_BREAK)
::SendMessage(port->m_pOwner->m_hWnd, WM_COMM_BREAK_DETECTED, (WPARAM) 0, (LPARAM) port->m_nPortNr);
if (CommEvent & EV_ERR)
::SendMessage(port->m_pOwner->m_hWnd, WM_COMM_ERR_DETECTED, (WPARAM) 0, (LPARAM) port->m_nPortNr);
if (CommEvent & EV_RING)
::SendMessage(port->m_pOwner->m_hWnd, WM_COMM_RING_DETECTED, (WPARAM) 0, (LPARAM) port->m_nPortNr);
if (CommEvent & EV_RXCHAR)
// Receive character event from port.
memset(&comstat, 0, sizeof(comstat));
ReceiveChar(port, comstat);
break;
}
case 2: // write event
{
// Write character event from port
WriteChar(port);
break;
}
} // end switch
} // close forever loop
return 0;
}
//
// start comm watching
//
BOOL CSerialPort::StartMonitoring()
{
if (!(m_Thread = AfxBeginThread(CommThread, this)))
return FALSE;
TRACE("Thread started\n");
return TRUE;
}
//
// Restart the comm thread
//
BOOL CSerialPort::RestartMonitoring()
{
TRACE("Thread resumed\n");
m_Thread->ResumeThread();
return TRUE;
}
//
// Suspend the comm thread
//
BOOL CSerialPort::StopMonitoring()
{
TRACE("Thread suspended\n");
m_Thread->SuspendThread();
return TRUE;
}
//
// If there is a error, give the right message
//
void CSerialPort::ProcessErrorMessage(char* ErrorText)
{
char *Temp = new char[200];
LPVOID lpMsgBuf;
FormatMessage(
FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM,
NULL,
GetLastError(),
MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), // Default language
(LPTSTR) &lpMsgBuf,
0,
NULL
);
sprintf(Temp, "WARNING: %s Failed with the following error: \n%s\nPort: %d\n", (char*)ErrorText, lpMsgBuf, m_nPortNr);
MessageBox(NULL, Temp, "Application Error", MB_ICONSTOP);
LocalFree(lpMsgBuf);
delete[] Temp;
}
//
// Write a character.
//
void CSerialPort::WriteChar(CSerialPort* port)
{
BOOL bWrite = TRUE;
BOOL bResult = TRUE;
DWORD BytesSent = 0;
ResetEvent(port->m_hWriteEvent);
// Gain ownership of the critical section
EnterCriticalSection(&port->m_csCommunicationSync);
if (bWrite)
{
// Initailize variables
port->m_ov.Offset = 0;
port->m_ov.OffsetHigh = 0;
// Clear buffer
PurgeComm(port->m_hComm, PURGE_RXCLEAR | PURGE_TXCLEAR | PURGE_RXABORT | PURGE_TXABORT);
bResult = WriteFile(port->m_hComm, // Handle to COMM Port
port->m_szWriteBuffer, // Pointer to message buffer in calling finction
strlen((char*)port->m_szWriteBuffer), // Length of message to send
&BytesSent, // Where to store the number of bytes sent
&port->m_ov); // Overlapped structure
// deal with any error codes
if (!bResult)
{
DWORD dwError = GetLastError();
switch (dwError)
{
case ERROR_IO_PENDING:
{
// continue to GetOverlappedResults()
BytesSent = 0;
bWrite = FALSE;
break;
}
default:
{
// all other error codes
port->ProcessErrorMessage("WriteFile()");
}
}
}
else
{
LeaveCriticalSection(&port->m_csCommunicationSync);
}
} // end if(bWrite)
if (!bWrite)
{
bWrite = TRUE;
bResult = GetOverlappedResult(port->m_hComm, // Handle to COMM port
&port->m_ov, // Overlapped structure
&BytesSent, // Stores number of bytes sent
TRUE); // Wait flag
LeaveCriticalSection(&port->m_csCommunicationSync);
// deal with the error code
if (!bResult)
{
port->ProcessErrorMessage("GetOverlappedResults() in WriteFile()");
}
} // end if (!bWrite)
// Verify that the data size send equals what we tried to send
if (BytesSent != strlen((char*)port->m_szWriteBuffer))
{
TRACE("WARNING: WriteFile() error.. Bytes Sent: %d; Message Length: %d\n", BytesSent, strlen((char*)port->m_szWriteBuffer));
}
}
//
// Character received. Inform the owner
//
void CSerialPort::ReceiveChar(CSerialPort* port, COMSTAT comstat)
{
BOOL bRead = TRUE;
BOOL bResult = TRUE;
DWORD dwError = 0;
DWORD BytesRead = 0;
unsigned char RXBuff;
for (;;)
{
// Gain ownership of the comm port critical section.
// This process guarantees no other part of this program
// is using the port object.
EnterCriticalSection(&port->m_csCommunicationSync);
// ClearCommError() will update the COMSTAT structure and
// clear any other errors.
bResult = ClearCommError(port->m_hComm, &dwError, &comstat);
LeaveCriticalSection(&port->m_csCommunicationSync);
// start forever loop. I use this type of loop because I
// do not know at runtime how many loops this will have to
// run. My solution is to start a forever loop and to
// break out of it when I have processed all of the
// data available. Be careful with this approach and
// be sure your loop will exit.
// My reasons for this are not as clear in this sample
// as it is in my production code, but I have found this
// solutiion to be the most efficient way to do this.
if (comstat.cbInQue == 0)
{
// break out when all bytes have been read
break;
}
EnterCriticalSection(&port->m_csCommunicationSync);
if (bRead)
{
bResult = ReadFile(port->m_hComm, // Handle to COMM port
&RXBuff, // RX Buffer Pointer
1, // Read one byte
&BytesRead, // Stores number of bytes read
&port->m_ov); // pointer to the m_ov structure
// deal with the error code
if (!bResult)
{
switch (dwError = GetLastError())
{
case ERROR_IO_PENDING:
{
// asynchronous i/o is still in progress
// Proceed on to GetOverlappedResults();
bRead = FALSE;
break;
}
default:
{
// Another error has occured. Process this error.
port->ProcessErrorMessage("ReadFile()");
break;
}
}
}
else
{
// ReadFile() returned complete. It is not necessary to call GetOverlappedResults()
bRead = TRUE;
}
} // close if (bRead)
if (!bRead)
{
bRead = TRUE;
bResult = GetOverlappedResult(port->m_hComm, // Handle to COMM port
&port->m_ov, // Overlapped structure
&BytesRead, // Stores number of bytes read
TRUE); // Wait flag
// deal with the error code
if (!bResult)
{
port->ProcessErrorMessage("GetOverlappedResults() in ReadFile()");
}
} // close if (!bRead)
LeaveCriticalSection(&port->m_csCommunicationSync);
// notify parent that a byte was received
::SendMessage((port->m_pOwner)->m_hWnd, WM_COMM_RXCHAR, (WPARAM) RXBuff, (LPARAM) port->m_nPortNr);
} // end forever loop
}
//
// Write a string to the port
//
void CSerialPort::WriteToPort(char* string)
{
assert(m_hComm != 0);
memset(m_szWriteBuffer, 0, sizeof(m_szWriteBuffer));
strcpy(m_szWriteBuffer, string);
// set event for write
SetEvent(m_hWriteEvent);
}
//
// Return the device control block
//
DCB CSerialPort::GetDCB()
{
return m_dcb;
}
//
// Return the communication event masks
//
DWORD CSerialPort::GetCommEvents()
{
return m_dwCommEvents;
}
//
// Return the output buffer size
//
DWORD CSerialPort::GetWriteBufferSize()
{
return m_nWriteBufferSize;
}