原博客网址:http://blog.csdn.NET/itas109
QQ技术交流群:129518033
这是一份优秀的串口类文件,好多的地方值得我们学习,具体在多线程,事件,自定义消息,类的封装方面等等。
Remon提供的串口类网址为: http://codeguru.earthweb.com/network/serialport.shtml,
由于已经运行十几年了,原文的问答部分列出来这么多年来的问题,经过网友们的总结,补充和修改原来代码后,整理出一份相对比较完美的代码。
CSerialPort类地址:https://github.com/itas109/CSerialPort
2016-08-02补充说明
优快云下载:http://download.youkuaiyun.com/detail/itas109/9598347
更新内容:
1、 改进IsOpen方法,m_hComm增加INVALID_HANDLE_VALUE的情况,因为CreateFile方法失败返回的是INVALID_HANDLE_VALUE,不是NULL
2、改进ClosePort方法:增加串口句柄无效的判断(防止关闭死锁);m_hWriteEvent不使用CloseHandle关闭
3、 改进CommThread、ReceiveChar、ReceiveStr和WriteChar方法中异常处理的判断,增加三种判断:串口打开失败(error code:ERROR_INVALID_HANDLE)、连接过程中非法断开(error code:ERROR_BAD_COMMAND)和拒绝访问(error code:ERROR_ACCESS_DENIED)
4、 采用安全函数sprintf_s和strcpy_s函数替换掉sprintf和strcpy
5、 改进QueryKey方法,用于查询注册表的可用串口值,可以搜索到任意的可用串口
6、改进InitPort方法,串口打开失败,增加提示信息:串口不存在(error code:ERROR_FILE_NOT_FOUND)和串口拒绝访问(error code:ERROR_ACCESS_DENIED)
7、加入viruscamp 取消对 MFC 的依赖
8、改进InitPort方法,如果上次串口是打开,再次调用InitPort方法,关闭串口需要做一定的延时,否则有几率导致ERROR_ACCESS_DENIED拒绝访问,也就是串口占用问题
9、初始化默认波特率修改为9600
10、修复一些释放的BUG
11、规范了一些错误信息,参考winerror.h -- error code definitions for the Win32 API functions
12、删除SendData和RecvData方法
2016-06-29补充说明:
优快云下载:http://download.csdn.Net/detail/itas109/9563059
更新内容:
1、解决RestartMonitoring方法和StopMonitoring方法命令不准确引起的歧义,根据实际作用。 将RestartMonitoring更改为ResumeMonitoring,将StopMonitoring更改为SuspendMonitoring。
2、增加IsThreadSuspend方法,用于判断线程是否挂起。
3、改进ClosePort方法,增加线程挂起判断,解决由于线程挂起导致串口关闭死锁的问题。
4、增加IsReceiveString宏定义,用于接收时采用单字节接收还是多字节接收。
2016-06-22补充说明:
更新内容:
1、增加ReceiveStr方法,用于接收字符串(接收缓冲区有多少字符就接收多少字符)。 解决ReceiveChar只能接收单个字符的问题。
2016-05-07补充说明:
优快云下载:http://download.youkuaiyun.com/detail/itas109/9512828
更新内容:
1、修复每次打开串口发送一次,当串口无应答时,需要关闭再打开或者接收完数据才能发送的问题。 解决办法:在m_hEventArray中调整m_hWriteEvent的优先级高于读的优先级。CommThread(LPVOID pParam)函数中读写的位置也调换。 参考:http://zhidao.baidu.com/link?url=RSrbPcfTZRULFFd2ziHZPBwnoXv1iCSu_Nmycb_yEw1mklT8gkoNZAkWpl3UDhk8L35DtRPo5VV5kEGpOx-Gea
2、修复停止位在头文件中定义成1导致SetCommState报错的问题,应为1对应的停止位是1.5。UINT stopsbits = ONESTOPBIT
3、switch(stopbits)和switch(parity)增加默认情况,增强程序健壮性
历史更新:
First Version by Remon Spekreijse on 2000-02-08
http://www.codeguru.com/cpp/i-n/network/serialcommunications/article.php/c2483/A-communication-class-for-serial-port.htm
Second Version by mrlong on 2007-12-25
https://code.google.com/p/mycom/
* 增加 ClosePort
* 增加 WriteToPort 两个方法
* 增加 SendData 与 RecvData 方法
by liquanhai on 2011-11-04
http://blog.youkuaiyun.com/liquanhai/article/details/4955253
* 增加 ClosePort 中交出控制权,防止死锁问题
by liquanhai on 2011-11-06
http://blog.youkuaiyun.com/liquanhai/article/details/6941574
* 增加 ReceiveChar 中防止线程死锁
by viruscamp on 2013-12-04
https://github.com/viruscamp/CSerialPort
* 增加 IsOpen 判断是否打开
* 修正 InitPort 中 parity Odd Even 参数取值错误
* 修改 InitPort 中 portnr 取值范围,portnr>9 时特殊处理
* 取消对 MFC 的依赖,使用 HWND 替代 CWnd,使用 win32 thread 函数而不是 MFC 的
* 增加用户消息编号自定义,方法来自 CnComm
by itas109 on 2014-01-10
http://blog.youkuaiyun.com/itas109/article/details/18358297
* 解决COM10以上端口无法显示的问题
* 扩展可选择端口,最大值MaxSerialPortNum可以自定义
* 添加QueryKey()和Hkey2ComboBox两个方法,用于自动查询当前有效的串口号。
by liquanhai on 2014-12-18
* 增加一些处理措施,主要是对减少CPU占用率
by itas109 on 2016-05-06
* 修复每次打开串口发送一次,当串口无应答时,需要关闭再打开或者接收完数据才能发送的问题。
解决办法:在m_hEventArray中调整m_hWriteEvent的优先级高于读的优先级。CommThread(LPVOID pParam)函数中读写的位置也调换。
参考:http://zhidao.baidu.com/link?url=RSrbPcfTZRULFFd2ziHZPBwnoXv1iCSu_Nmycb_yEw1mklT8gkoNZAkWpl3UDhk8L35DtRPo5VV5kEGpOx-Gea
* 修复停止位在头文件中定义成1导致SetCommState报错的问题,应为1对应的停止位是1.5。UINT stopsbits = ONESTOPBIT
* switch(stopbits)和switch(parity)增加默认情况,增强程序健壮性
by itas109 on 2016-06-22
* 增加ReceiveStr方法,用于接收字符串(接收缓冲区有多少字符就接收多少字符)。
* 解决ReceiveChar只能接收单个字符的问题。
by itas109 on 2016-06-29
* 解决RestartMonitoring方法和StopMonitoring方法命令不准确引起的歧义,根据实际作用。
* 将RestartMonitoring更改为ResumeMonitoring,将StopMonitoring更改为SuspendMonitoring。
* 增加IsThreadSuspend方法,用于判断线程是否挂起。
* 改进ClosePort方法,增加线程挂起判断,解决由于线程挂起导致串口关闭死锁的问题。
* 增加IsReceiveString宏定义,用于接收时采用单字节接收还是多字节接收
- /*
- ** 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
- **
- **
- ************************************************************************************
- ** author: mrlong date:2007-12-25
- **
- ** 改进
- ** 1) 增加 ClosePort
- ** 2) 增加 WriteToPort 两个方法
- ** 3) 增加 SendData 与 RecvData 方法
- **************************************************************************************
- ***************************************************************************************
- ** author:liquanhai date:2011-11-06
- **
- ** 改进
- ** 1) 增加 ClosePort 中交出控制权,防止死锁问题
- ** 2) 增加 ReceiveChar 中防止线程死锁
- **************************************************************************************
- ***************************************************************************************
- ** author:viruscamp date:2013-12-04
- **
- ** 改进
- ** 1) 增加 IsOpen 判断是否打开
- ** 2) 修正 InitPort 中 parity Odd Even 参数取值错误
- ** 3) 修改 InitPort 中 portnr 取值范围,portnr>9 时特殊处理
- ** 4) 取消对 MFC 的依赖,使用 HWND 替代 CWnd,使用 win32 thread 函数而不是 MFC 的
- ** 5) 增加用户消息编号自定义,方法来自 CnComm
- ***************************************************************************************
- ***************************************************************************************
- ** author: itas109 date:2014-01-10
- ** Blog:blog.youkuaiyun.com/itas109
- ** Git:https://github.com/itas109
- **
- ** 改进
- ** 1) 解决COM10以上端口无法显示的问题
- ** 2) 扩展可选择端口,最大值MaxSerialPortNum可以自定义
- ** 3) 添加QueryKey()和Hkey2ComboBox两个方法,用于自动查询当前有效的串口号。
- ***************************************************************************************
- ** author: liquanhai date:2014-12-18
- **
- ** 增加一些处理措施,主要是对减少CPU占用率
- ***************************************************************************************
- ** author: itas109 date:2016-05-06
- ** Blog:blog.youkuaiyun.com/itas109
- ** Git:https://github.com/itas109
- **
- ** 改进
- ** 1) 修复每次打开串口发送一次,当串口无应答时,需要关闭再打开或者接收完数据才能发送的问题。
- ** 解决办法:在m_hEventArray中调整m_hWriteEvent的优先级高于读的优先级。CommThread(LPVOID pParam)函数中读写的位置也调换。
- ** 参考:http://zhidao.baidu.com/link?url=RSrbPcfTZRULFFd2ziHZPBwnoXv1iCSu_Nmycb_yEw1mklT8gkoNZAkWpl3UDhk8L35DtRPo5VV5kEGpOx-Gea
- ** 2) 修复停止位在头文件中定义成1导致SetCommState报错的问题,应为1对应的停止位是1.5。UINT stopsbits = ONESTOPBIT
- ** 3) switch(stopbits)和switch(parity)增加默认情况,增强程序健壮性
- ** ***************************************************************************************
- ** author: itas109 date:2016-06-22
- ** Blog:blog.youkuaiyun.com/itas109
- ** Git:https://github.com/itas109
- **
- ** 改进
- ** 1) 增加ReceiveStr方法,用于接收字符串(接收缓冲区有多少字符就接收多少字符)。
- ** 解决ReceiveChar只能接收单个字符的问题。
- ** ***************************************************************************************
- ** author: itas109 date:2016-06-29
- ** Blog:blog.youkuaiyun.com/itas109
- ** Git:https://github.com/itas109
- **
- ** 改进
- ** 1) 解决RestartMonitoring方法和StopMonitoring方法命令不准确引起的歧义,根据实际作用。
- ** 将RestartMonitoring更改为ResumeMonitoring,将StopMonitoring更改为SuspendMonitoring。
- ** 2) 增加IsThreadSuspend方法,用于判断线程是否挂起。
- ** 3) 改进ClosePort方法,增加线程挂起判断,解决由于线程挂起导致串口关闭死锁的问题。
- ** 4) 增加IsReceiveString宏定义,用于接收时采用单字节接收还是多字节接收
- ** ***************************************************************************************
- ** author: itas109 date:2016-08-02
- ** Blog:blog.youkuaiyun.com/itas109
- ** Git:https://github.com/itas109
- **
- ** 改进
- ** 1) 改进IsOpen方法,m_hComm增加INVALID_HANDLE_VALUE的情况,因为CreateFile方法失败返回的是INVALID_HANDLE_VALUE,不是NULL
- ** 2) 改进ClosePort方法:增加串口句柄无效的判断(防止关闭死锁);m_hWriteEvent不使用CloseHandle关闭
- ** 3) 改进CommThread、ReceiveChar、ReceiveStr和WriteChar方法中异常处理的判断,增加三种判断:串口打开失败(error code:ERROR_INVALID_HANDLE)、连接过程中非法断开(error code:ERROR_BAD_COMMAND)和拒绝访问(error code:ERROR_ACCESS_DENIED)
- ** 4) 采用安全函数sprintf_s和strcpy_s函数替换掉sprintf和strcpy
- ** 5) 改进QueryKey方法,用于查询注册表的可用串口值,可以搜索到任意的可用串口
- ** 6) 改进InitPort方法,串口打开失败,增加提示信息:串口不存在(error code:ERROR_FILE_NOT_FOUND)和串口拒绝访问(error code:ERROR_ACCESS_DENIED)
- ** 7) 加入viruscamp 取消对 MFC 的依赖
- ** 8) 改进InitPort方法,如果上次串口是打开,再次调用InitPort方法,关闭串口需要做一定的延时,否则有几率导致ERROR_ACCESS_DENIED拒绝访问,也就是串口占用问题
- ** 9) 初始化默认波特率修改为9600
- ** 10)修复一些释放的BUG
- ** 11)规范了一些错误信息,参考winerror.h -- error code definitions for the Win32 API functions
- ** 12)删除SendData和RecvData方法
- */
- #ifndef __SERIALPORT_H__
- #define __SERIALPORT_H__
- #ifndef WM_COMM_MSG_BASE
- #define WM_COMM_MSG_BASE WM_USER + 617 //!< 消息编号的基点
- #endif
- #define WM_COMM_BREAK_DETECTED WM_COMM_MSG_BASE + 1 // A break was detected on input.
- #define WM_COMM_CTS_DETECTED WM_COMM_MSG_BASE + 2 // The CTS (clear-to-send) signal changed state.
- #define WM_COMM_DSR_DETECTED WM_COMM_MSG_BASE + 3 // The DSR (data-set-ready) signal changed state.
- #define WM_COMM_ERR_DETECTED WM_COMM_MSG_BASE + 4 // A line-status error occurred. Line-status errors are CE_FRAME, CE_OVERRUN, and CE_RXPARITY.
- #define WM_COMM_RING_DETECTED WM_COMM_MSG_BASE + 5 // A ring indicator was detected.
- #define WM_COMM_RLSD_DETECTED WM_COMM_MSG_BASE + 6 // The RLSD (receive-line-signal-detect) signal changed state.
- #define WM_COMM_RXCHAR WM_COMM_MSG_BASE + 7 // A character was received and placed in the input buffer.
- #define WM_COMM_RXFLAG_DETECTED WM_COMM_MSG_BASE + 8 // The event character was received and placed in the input buffer.
- #define WM_COMM_TXEMPTY_DETECTED WM_COMM_MSG_BASE + 9 // The last character in the output buffer was sent.
- #define WM_COMM_RXSTR WM_COMM_MSG_BASE + 10 // Receive string
- #define MaxSerialPortNum 200 ///有效的串口总个数,不是串口的号 //add by itas109 2014-01-09
- #define IsReceiveString 1 //采用何种方式接收:ReceiveString 1多字符串接收(对应响应函数为WM_COMM_RXSTR),ReceiveString 0一个字符一个字符接收(对应响应函数为WM_COMM_RXCHAR)
- class CSerialPort
- {
- public:
- // contruction and destruction
- CSerialPort();
- virtual ~CSerialPort( );
- // port initialisation
- // UINT stopsbits = ONESTOPBIT stop is index 0 = 1 1=1.5 2=2
- // 切记:stopsbits = 1,不是停止位为1。
- // by itas109 20160506
- BOOL InitPort(HWND pPortOwner, UINT portnr = 1, UINT baud = 9600,
- char parity = 'N', UINT databits = 8, UINT stopsbits = ONESTOPBIT,
- DWORD dwCommEvents = EV_RXCHAR | EV_CTS, UINT nBufferSize = 512,
- DWORD ReadIntervalTimeout = 1000,
- DWORD ReadTotalTimeoutMultiplier = 1000,
- DWORD ReadTotalTimeoutConstant = 1000,
- DWORD WriteTotalTimeoutMultiplier = 1000,
- DWORD WriteTotalTimeoutConstant = 1000);
- // start/stop comm watching
- ///控制串口监视线程
- BOOL StartMonitoring();//开始监听
- BOOL ResumeMonitoring();//恢复监听
- BOOL SuspendMonitoring();//挂起监听
- BOOL IsThreadSuspend(HANDLE hThread);//判断线程是否挂起 //add by itas109 2016-06-29
- DWORD GetWriteBufferSize();///获取写缓冲大小
- DWORD GetCommEvents();///获取事件
- DCB GetDCB();///获取DCB
- ///写数据到串口
- void WriteToPort(char* string);
- void WriteToPort(char* string,int n); // add by mrlong 2007-12-25
- void WriteToPort(LPCTSTR string); // add by mrlong 2007-12-25
- void WriteToPort(LPCTSTR string,int n);//add by mrlong 2007-12-2
- void WriteToPort(BYTE* Buffer, int n);// add by mrlong
- void ClosePort(); // add by mrlong 2007-12-2
- BOOL IsOpen();
- //void SendData(LPCTSTR lpszData, const int nLength); //串口发送函数 by mrlong 2008-2-15
- //BOOL RecvData(LPTSTR lpszData, const int nSize); //串口接收函数 by mrlong 2008-2-15
- void QueryKey(HKEY hKey);///查询注册表的串口号,将值存于数组中
- void Hkey2ComboBox(CComboBox& m_PortNO);///将QueryKey查询到的串口号添加到CComboBox控件中
- protected:
- // protected memberfunctions
- void ProcessErrorMessage(char* ErrorText);///错误处理
- static DWORD WINAPI CommThread(LPVOID pParam);///线程函数
- static void ReceiveChar(CSerialPort* port);
- static void ReceiveStr(CSerialPort* port); //add by itas109 2016-06-22
- static void WriteChar(CSerialPort* port);
- // thread
- //CWinThread* m_Thread;
- HANDLE m_Thread;
- BOOL m_bIsSuspened;///thread监视线程是否挂起
- // synchronisation objects
- CRITICAL_SECTION m_csCommunicationSync;///临界资源
- BOOL m_bThreadAlive;///监视线程运行标志
- // handles
- HANDLE m_hShutdownEvent; //stop发生的事件
- HANDLE m_hComm; // 串口句柄
- HANDLE m_hWriteEvent; // write
- // 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.
- ///事件数组,包括一个写事件,接收事件,关闭事件
- ///一个元素用于一个事件。有两个事件线程处理端口。
- ///写事件和接收字符事件位于overlapped结构体(m_ov.hEvent)中
- ///当端口关闭时,有一个通用的关闭。
- HANDLE m_hEventArray[3];
- // structures
- OVERLAPPED m_ov;///异步I/O
- COMMTIMEOUTS m_CommTimeouts;///超时设置
- DCB m_dcb;///设备控制块
- // owner window
- //CWnd* m_pOwner;
- HWND m_pOwner;
- // misc
- UINT m_nPortNr; ///串口号
- char* m_szWriteBuffer;///写缓冲区
- DWORD m_dwCommEvents;
- DWORD m_nWriteBufferSize;///写缓冲大小
- int m_nWriteSize;//写入字节数 //add by mrlong 2007-12-25
- };
- #endif __SERIALPORT_H__
- /*
- ** 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
- **
- ** 2007-12-25 mrlong https://code.google.com/p/mycom/
- ** 2011-11-06 liquanhai http://blog.youkuaiyun.com/liquanhai/article/details/6941574
- ** 2013-12-04 viruscamp https://github.com/viruscamp
- ** 2014-01-10 itas109 http://blog.youkuaiyun.com/itas109
- ** 2014-12-18 liquanhai http://blog.youkuaiyun.com/liquanhai/article/details/6941574
- ** 2016-05-06 itas109 http://blog.youkuaiyun.com/itas109
- ** 2016-06-22 itas109 http://blog.youkuaiyun.com/itas109
- ** 2016-06-29 itas109 http://blog.youkuaiyun.com/itas109
- ** 2016-08-02 itas109 http://blog.youkuaiyun.com/itas109
- */
- #include "stdafx.h"
- #include "SerialPort.h"
- #include <assert.h>
- int m_nComArray[20];//存放活跃的串口号
- //
- // Constructor
- //
- CSerialPort::CSerialPort()
- {
- m_hComm = NULL;
- // initialize overlapped structure members to zero
- ///初始化异步结构体
- 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;
- m_nWriteSize = 1;
- m_bIsSuspened = FALSE;
- }
- //
- // Delete dynamic memory
- //
- CSerialPort::~CSerialPort()
- {
- MSG message;
- //增加线程挂起判断,解决由于线程挂起导致串口关闭死锁的问题 add by itas109 2016-06-29
- if(IsThreadSuspend(m_Thread))
- {
- ResumeThread(m_Thread);
- }
- //串口句柄无效 add by itas109 2016-07-29
- if(m_hComm == INVALID_HANDLE_VALUE)
- {
- CloseHandle(m_hComm);
- m_hComm = NULL;
- return;
- }
- do
- {
- SetEvent(m_hShutdownEvent);
- //add by liquanhai 防止死锁 2011-11-06
- if(::PeekMessage(&message,m_pOwner,0,0,PM_REMOVE))
- {
- ::TranslateMessage(&message);
- ::DispatchMessage(&message);
- }
- } while (m_bThreadAlive);
- // if the port is still opened: close it
- if (m_hComm != NULL)
- {
- CloseHandle(m_hComm);
- m_hComm = NULL;
- }
- // Close Handles
- if(m_hShutdownEvent!=NULL)
- CloseHandle( m_hShutdownEvent);
- if(m_ov.hEvent!=NULL)
- CloseHandle( m_ov.hEvent );
- if(m_hWriteEvent!=NULL)
- CloseHandle( m_hWriteEvent );
- //TRACE("Thread ended\n");
- if(m_szWriteBuffer != NULL)
- {
- delete [] m_szWriteBuffer;
- m_szWriteBuffer = NULL;
- }
- }
- //
- // Initialize the port. This can be port 1 to MaxSerialPortNum.
- ///初始化串口。只能是1-MaxSerialPortNum
- //
- //parity:
- // n=none
- // e=even
- // o=odd
- // m=mark
- // s=space
- //data:
- // 5,6,7,8
- //stop:
- // 1,1.5,2
- //
- BOOL CSerialPort::InitPort(HWND pPortOwner, // the owner (CWnd) of the port (receives message)
- UINT portnr, // portnumber (1..MaxSerialPortNum)
- 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
- DWORD ReadIntervalTimeout,
- DWORD ReadTotalTimeoutMultiplier,
- DWORD ReadTotalTimeoutConstant,
- DWORD WriteTotalTimeoutMultiplier,
- DWORD WriteTotalTimeoutConstant )
- {
- assert(portnr > 0 && portnr < MaxSerialPortNum);
- assert(pPortOwner != NULL);
- MSG message;
- //增加线程挂起判断,解决由于线程挂起导致串口关闭死锁的问题 add by itas109 2016-06-29
- if(IsThreadSuspend(m_Thread))
- {
- ResumeThread(m_Thread);
- }
- // if the thread is alive: Kill
- if (m_bThreadAlive)
- {
- do
- {
- SetEvent(m_hShutdownEvent);
- //add by liquanhai 防止死锁 2011-11-06
- if(::PeekMessage(&message,m_pOwner,0,0,PM_REMOVE))
- {
- ::TranslateMessage(&message);
- ::DispatchMessage(&message);
- }
- } while (m_bThreadAlive);
- //TRACE("Thread ended\n");
- //此处的延时很重要,因为如果串口开着,发送关闭指令到彻底关闭需要一定的时间,这个延时应该跟电脑的性能相关
- Sleep(50);//add by itas109 2016-08-02
- }
- // create events
- if (m_ov.hEvent != NULL)
- ResetEvent(m_ov.hEvent);
- else
- m_ov.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
- if (m_hWriteEvent != NULL)
- ResetEvent(m_hWriteEvent);
- else
- m_hWriteEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
- if (m_hShutdownEvent != NULL)
- ResetEvent(m_hShutdownEvent);
- else
- m_hShutdownEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
- // initialize the event objects
- ///事件数组初始化,设定优先级别
- m_hEventArray[0] = m_hShutdownEvent; // highest priority
- //为避免有些串口设备无数据输入,但一直返回读事件,使监听线程阻塞,
- //可以将读写放在两个线程中,或者修改读写事件优先级
- //修改优先级有两个方案:
- //方案一为监听线程中WaitCommEvent()后,添加如下两条语句:
- //if (WAIT_OBJECT_O == WaitForSingleObject(port->m_hWriteEvent, 0))
- // ResetEvent(port->m_ov.hEvent);
- //方案二为初始化时即修改,即下面两条语句:
- m_hEventArray[1] = m_hWriteEvent;
- m_hEventArray[2] = m_ov.hEvent;
- // initialize critical section
- ///初始化临界资源
- InitializeCriticalSection(&m_csCommunicationSync);
- // set buffersize for writing and save the owner
- m_pOwner = pPortOwner;
- if(m_szWriteBuffer != NULL)
- {
- delete [] m_szWriteBuffer;
- m_szWriteBuffer = NULL;
- }
- 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];
- /*
- 多个线程操作相同的数据时,一般是需要按顺序访问的,否则会引导数据错乱,
- 无法控制数据,变成随机变量。为解决这个问题,就需要引入互斥变量,让每
- 个线程都按顺序地访问变量。这样就需要使用EnterCriticalSection和
- LeaveCriticalSection函数。
- */
- // now it critical!
- EnterCriticalSection(&m_csCommunicationSync);
- // if the port is already opened: close it
- ///串口已打开就关掉
- if (m_hComm != NULL)
- {
- CloseHandle(m_hComm);
- m_hComm = NULL;
- }
- // prepare port strings
- sprintf_s(szPort,50, "\\\\.\\COM%d", portnr);///可以显示COM10以上端口//add by itas109 2014-01-09
- // stop is index 0 = 1 1=1.5 2=2
- int mystop;
- int myparity;
- switch(stopbits)
- {
- case 0:
- mystop = ONESTOPBIT;
- break;
- case 1:
- mystop = ONE5STOPBITS;
- break;
- case 2:
- mystop = TWOSTOPBITS;
- break;
- //增加默认情况,因为stopbits=1.5时,SetCommState会报错。
- //一般的电脑串口不支持1.5停止位,这个1.5停止位似乎用在红外传输上的。
- //by itas109 20160506
- default:
- mystop = ONESTOPBIT;
- break;
- }
- myparity = 0;
- parity = toupper(parity);
- switch(parity)
- {
- case 'N':
- myparity = 0;
- break;
- case 'O':
- myparity = 1;
- break;
- case 'E':
- myparity = 2;
- break;
- case 'M':
- myparity = 3;
- break;
- case 'S':
- myparity = 4;
- break;
- //增加默认情况。
- //by itas109 20160506
- default:
- myparity = 0;
- break;
- }
- sprintf_s(szBaud,50, "baud=%d parity=%c data=%d stop=%d", baud, parity, databits, mystop);
- // get a handle to the port
- /*
- 通信程序在CreateFile处指定串口设备及相关的操作属性,再返回一个句柄,
- 该句柄将被用于后续的通信操作,并贯穿整个通信过程串口打开后,其属性
- 被设置为默认值,根据具体需要,通过调用GetCommState(hComm,&&dcb)读取
- 当前串口设备控制块DCB设置,修改后通过SetCommState(hComm,&&dcb)将其写
- 入。运用ReadFile()与WriteFile()这两个API函数实现串口读写操作,若为异
- 步通信方式,两函数中最后一个参数为指向OVERLAPPED结构的非空指针,在读
- 写函数返回值为FALSE的情况下,调用GetLastError()函数,返回值为ERROR_IO_PENDING,
- 表明I/O操作悬挂,即操作转入后台继续执行。此时,可以用WaitForSingleObject()
- 来等待结束信号并设置最长等待时间
- */
- 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
- ///创建失败
- if (m_hComm == INVALID_HANDLE_VALUE)
- {
- //add by itas109 2016-08-02
- //串口打开失败,增加提示信息
- switch(GetLastError())
- {
- //串口不存在
- case ERROR_FILE_NOT_FOUND:
- {
- CString str;
- str.Format("COM%d ERROR_FILE_NOT_FOUND,Error Code:%d",portnr,GetLastError());
- AfxMessageBox(str);
- break;
- }
- //串口拒绝访问
- case ERROR_ACCESS_DENIED:
- {
- CString str;
- str.Format("COM%d ERROR_ACCESS_DENIED,Error Code:%d",portnr,GetLastError());
- AfxMessageBox(str);
- break;
- }
- default:
- break;
- }
- // port not found
- delete [] szPort;
- delete [] szBaud;
- return FALSE;
- }
- // set the timeout values
- ///设置超时
- m_CommTimeouts.ReadIntervalTimeout = ReadIntervalTimeout * 1000;
- m_CommTimeouts.ReadTotalTimeoutMultiplier = ReadTotalTimeoutMultiplier * 1000;
- m_CommTimeouts.ReadTotalTimeoutConstant = ReadTotalTimeoutConstant * 1000;
- m_CommTimeouts.WriteTotalTimeoutMultiplier = WriteTotalTimeoutMultiplier * 1000;
- m_CommTimeouts.WriteTotalTimeoutConstant = WriteTotalTimeoutConstant * 1000;
- // configure
- ///配置
- ///分别调用Windows API设置串口参数
- if (SetCommTimeouts(m_hComm, &m_CommTimeouts))///设置超时
- {
- /*
- 若对端口数据的响应时间要求较严格,可采用事件驱动方式。
- 事件驱动方式通过设置事件通知,当所希望的事件发生时,Windows
- 发出该事件已发生的通知,这与DOS环境下的中断方式很相似。Windows
- 定义了9种串口通信事件,较常用的有以下三种:
- EV_RXCHAR:接收到一个字节,并放入输入缓冲区;
- EV_TXEMPTY:输出缓冲区中的最后一个字符,发送出去;
- EV_RXFLAG:接收到事件字符(DCB结构中EvtChar成员),放入输入缓冲区
- 在用SetCommMask()指定了有用的事件后,应用程序可调用WaitCommEvent()来等待事
- 件的发生。SetCommMask(hComm,0)可使WaitCommEvent()中止
- */
- if (SetCommMask(m_hComm, dwCommEvents))///设置通信事件
- {
- if (GetCommState(m_hComm, &m_dcb))///获取当前DCB参数
- {
- m_dcb.EvtChar = 'q';
- m_dcb.fRtsControl = RTS_CONTROL_ENABLE; // set RTS bit high!
- m_dcb.BaudRate = baud; // add by mrlong
- m_dcb.Parity = myparity;
- m_dcb.ByteSize = databits;
- m_dcb.StopBits = mystop;
- //if (BuildCommDCB(szBaud &m_dcb))///填写DCB结构
- //{
- if (SetCommState(m_hComm, &m_dcb))///配置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
- ///终止读写并清空接收和发送
- PurgeComm(m_hComm, PURGE_RXCLEAR | PURGE_TXCLEAR | PURGE_RXABORT | PURGE_TXABORT);
- // release critical section
- ///释放临界资源
- LeaveCriticalSection(&m_csCommunicationSync);
- //TRACE("Initialisation for communicationport %d completed.\nUse Startmonitor to communicate.\n", portnr);
- return TRUE;
- }
- //
- // The CommThread Function.
- ///线程函数
- ///监视线程的大致流程:
- ///检查串口-->进入循环{WaitCommEvent(不阻塞询问)询问事件-->如果有事件来到-->到相应处理(关闭\读\写)}
- //
- DWORD WINAPI 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.
- ///TRUE表示线程正在运行
- 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
- ///开始时清除串口缓冲
- 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.
- ///只要线程存在就不断读取数据
- 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!
- /*
- WaitCommEvent函数第3个参数1pOverlapped可以是一个OVERLAPPED结构的变量指针
- ,也可以是NULL,当用NULL时,表示该函数是同步的,否则表示该函数是异步的。
- 调用WaitCommEvent时,如果异步操作不能立即完成,会立即返回FALSE,系统在
- WaitCommEvent返回前将OVERLAPPED结构成员hEvent设为无信号状态,等到产生通信
- 事件时,系统将其置有信号
- */
- bResult = WaitCommEvent(port->m_hComm, &Event, &port->m_ov);///表示该函数是异步的
- if (!bResult)
- {
- // If WaitCommEvent() returns FALSE, process the last error to determin
- // the reason..
- ///如果WaitCommEvent返回Error为FALSE,则查询错误信息
- switch (dwError = GetLastError())
- {
- case ERROR_IO_PENDING: ///正常情况,没有字符可读 erroe code:997
- {
- // This is a normal return value if there are no bytes
- // to read at the port.
- // Do nothing and continue
- break;
- }
- case ERROR_INVALID_PARAMETER:///系统错误 erroe code: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;
- }
- case ERROR_ACCESS_DENIED:///拒绝访问 erroe code:5
- {
- port->m_hComm = INVALID_HANDLE_VALUE;
- CString str;
- str.Format("COM%d ERROR_ACCESS_DENIED,WaitCommEvent() Error Code:%d",port->m_nPortNr,GetLastError());
- AfxMessageBox(str);
- break;
- }
- case ERROR_INVALID_HANDLE:///打开串口失败 erroe code:6
- {
- port->m_hComm = INVALID_HANDLE_VALUE;
- break;
- }
- case ERROR_BAD_COMMAND:///连接过程中非法断开 erroe code:22
- {
- port->m_hComm = INVALID_HANDLE_VALUE;
- CString str;
- str.Format("COM%d ERROR_BAD_COMMAND,WaitCommEvent() Error Code:%d",port->m_nPortNr,GetLastError());
- AfxMessageBox(str);
- break;
- }
- default:///发生其他错误,其中有串口读写中断开串口连接的错误(错误22)
- {
- // All other error codes indicate a serious error has
- //发生错误时,将串口句柄置为无效句柄
- port->m_hComm = INVALID_HANDLE_VALUE;
- // occured. Process this error.
- port->ProcessErrorMessage("WaitCommEvent()");
- break;
- }
- }
- }
- else ///WaitCommEvent()能正确返回
- {
- // 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
- ///主等待函数,会阻塞线程
- // Main wait function. This function will normally block the thread
- // until one of nine events occur that require action.
- ///等待3个事件:关断/读/写,有一个事件发生就返回
- Event = WaitForMultipleObjects(3, ///3个事件
- port->m_hEventArray, ///事件数组
- FALSE, ///有一个事件发生就返回
- INFINITE);///超时时间
- switch (Event)
- {
- case 0:
- {
- // Shutdown event. This is event zero so it will be
- // the higest priority and be serviced first.
- ///关断事件,关闭串口
- CloseHandle(port->m_hComm);
- port->m_hComm=NULL;
- port->m_bThreadAlive = FALSE;
- // Kill this thread. break is not needed, but makes me feel better.
- //AfxEndThread(100);
- ::ExitThread(100);
- break;
- }
- case 1: // write event 发送数据
- {
- // Write character event from port
- WriteChar(port);
- break;
- }
- case 2: // read event 将定义的各种消息发送出去
- {
- GetCommMask(port->m_hComm, &CommEvent);
- if (CommEvent & EV_RXCHAR) //接收到字符,并置于输入缓冲区中
- {
- if (IsReceiveString == 1)
- {
- ReceiveStr(port);//多字符接收
- }
- else if (IsReceiveString == 0)
- {
- ReceiveChar(port);//单字符接收
- }
- else
- {
- //默认多字符接收
- ReceiveStr(port);//多字符接收
- }
- }
- if (CommEvent & EV_CTS) //CTS信号状态发生变化
- ::SendMessage(port->m_pOwner, WM_COMM_CTS_DETECTED, (WPARAM) 0, (LPARAM) port->m_nPortNr);
- if (CommEvent & EV_RXFLAG) //接收到事件字符,并置于输入缓冲区中
- ::SendMessage(port->m_pOwner, WM_COMM_RXFLAG_DETECTED, (WPARAM) 0, (LPARAM) port->m_nPortNr);
- if (CommEvent & EV_BREAK) //输入中发生中断
- ::SendMessage(port->m_pOwner, WM_COMM_BREAK_DETECTED, (WPARAM) 0, (LPARAM) port->m_nPortNr);
- if (CommEvent & EV_ERR) //发生线路状态错误,线路状态错误包括CE_FRAME,CE_OVERRUN和CE_RXPARITY
- ::SendMessage(port->m_pOwner, WM_COMM_ERR_DETECTED, (WPARAM) 0, (LPARAM) port->m_nPortNr);
- if (CommEvent & EV_RING) //检测到振铃指示
- ::SendMessage(port->m_pOwner, WM_COMM_RING_DETECTED, (WPARAM) 0, (LPARAM) port->m_nPortNr);
- break;
- }
- default:
- {
- AfxMessageBox("接收有问题!");
- break;
- }
- } // end switch
- } // close forever loop
- return 0;
- }
- //
- // start comm watching
- ///开启监视线程
- //
- BOOL CSerialPort::StartMonitoring()
- {
- //if (!(m_Thread = AfxBeginThread(CommThread, this)))
- if (!(m_Thread = ::CreateThread (NULL, 0, CommThread, this, 0, NULL )))
- return FALSE;
- //TRACE("Thread started\n");
- return TRUE;
- }
- //
- // Restart the comm thread
- ///从挂起恢复监视线程
- //
- BOOL CSerialPort::ResumeMonitoring()
- {
- //TRACE("Thread resumed\n");
- //m_Thread->ResumeThread();
- ::ResumeThread(m_Thread);
- return TRUE;
- }
- //
- // Suspend the comm thread
- ///挂起监视线程
- //
- BOOL CSerialPort::SuspendMonitoring()
- {
- //TRACE("Thread suspended\n");
- //m_Thread->SuspendThread();
- ::SuspendThread(m_Thread);
- return TRUE;
- }
- BOOL CSerialPort::IsThreadSuspend(HANDLE hThread)
- {
- DWORD count = SuspendThread(hThread);
- if (count == -1)
- {
- return FALSE;
- }
- ResumeThread(hThread);
- return (count != 0);
- }
- //
- // If there is a error, give the right message
- ///如果有错误,给出提示
- //
- 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_s(Temp,200,"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;
- DWORD SendLen = port->m_nWriteSize;
- 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
- SendLen, // add by mrlong
- //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;
- }
- case ERROR_ACCESS_DENIED:///拒绝访问 erroe code:5
- {
- port->m_hComm = INVALID_HANDLE_VALUE;
- CString str;
- str.Format("COM%d ERROR_ACCESS_DENIED,WriteFile() Error Code:%d",port->m_nPortNr,GetLastError());
- AfxMessageBox(str);
- break;
- }
- case ERROR_INVALID_HANDLE:///打开串口失败 erroe code:6
- {
- port->m_hComm = INVALID_HANDLE_VALUE;
- break;
- }
- case ERROR_BAD_COMMAND:///连接过程中非法断开 erroe code:22
- {
- port->m_hComm = INVALID_HANDLE_VALUE;
- CString str;
- str.Format("COM%d ERROR_BAD_COMMAND,WriteFile() Error Code:%d",port->m_nPortNr,GetLastError());
- AfxMessageBox(str);
- 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 != SendLen /*strlen((char*)port->m_szWriteBuffer)*/) // add by
- {
- //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)
- {
- BOOL bRead = TRUE;
- BOOL bResult = TRUE;
- DWORD dwError = 0;
- DWORD BytesRead = 0;
- COMSTAT comstat;
- unsigned char RXBuff;
- for (;;)
- {
- //add by liquanhai 2011-11-06 防止死锁
- if(WaitForSingleObject(port->m_hShutdownEvent,0)==WAIT_OBJECT_0)
- return;
- // 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.
- ///更新COMSTAT
- 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.
- ///所有字符均被读出,中断循环
- if (comstat.cbInQue == 0)
- {
- // break out when all bytes have been read
- break;
- }
- EnterCriticalSection(&port->m_csCommunicationSync);
- if (bRead)
- {
- ///串口读出,读出缓冲区中字节
- 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
- ///若返回错误,错误处理
- if (!bResult)
- {
- switch (dwError = GetLastError())
- {
- case ERROR_IO_PENDING:
- {
- // asynchronous i/o is still in progress
- // Proceed on to GetOverlappedResults();
- ///异步IO仍在进行
- bRead = FALSE;
- break;
- }
- case ERROR_ACCESS_DENIED:///拒绝访问 erroe code:5
- {
- port->m_hComm = INVALID_HANDLE_VALUE;
- CString str;
- str.Format("COM%d ERROR_ACCESS_DENIED,ReadFile() Error Code:%d",port->m_nPortNr,GetLastError());
- AfxMessageBox(str);
- break;
- }
- case ERROR_INVALID_HANDLE:///打开串口失败 erroe code:6
- {
- port->m_hComm = INVALID_HANDLE_VALUE;
- break;
- }
- case ERROR_BAD_COMMAND:///连接过程中非法断开 erroe code:22
- {
- port->m_hComm = INVALID_HANDLE_VALUE;
- CString str;
- str.Format("COM%d ERROR_BAD_COMMAND,ReadFile() Error Code:%d",port->m_nPortNr,GetLastError());
- AfxMessageBox(str);
- break;
- }
- default:
- {
- // Another error has occured. Process this error.
- port->ProcessErrorMessage("ReadFile()");
- break;
- //return;///防止读写数据时,串口非正常断开导致死循环一直执行。add by itas109 2014-01-09 与上面liquanhai添加防死锁的代码差不多
- }
- }
- }
- else///ReadFile返回TRUE
- {
- // ReadFile() returned complete. It is not necessary to call GetOverlappedResults()
- bRead = TRUE;
- }
- } // close if (bRead)
- ///异步IO操作仍在进行,需要调用GetOverlappedResult查询
- 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
- //避免线程互相等待,产生死锁,使用PostMessage()代替SendMessage()
- PostMessage(port->m_pOwner, WM_COMM_RXCHAR, (WPARAM)RXBuff, (LPARAM) port->m_nPortNr);
- //::SendMessage((port->m_pOwner), WM_COMM_RXCHAR, (WPARAM) RXBuff, (LPARAM) port->m_nPortNr);
- } // end forever loop
- }
- //
- // str received. Inform the owner
- //
- void CSerialPort::ReceiveStr(CSerialPort* port)
- {
- BOOL bRead = TRUE;
- BOOL bResult = TRUE;
- DWORD dwError = 0;
- DWORD BytesRead = 0;
- COMSTAT comstat;
- for (;;)
- {
- //add by liquanhai 2011-11-06 防止死锁
- if(WaitForSingleObject(port->m_hShutdownEvent,0)==WAIT_OBJECT_0)
- return;
- // 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.
- ///更新COMSTAT
- 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.
- ///所有字符均被读出,中断循环
- if (comstat.cbInQue == 0)
- {
- // break out when all bytes have been read
- break;
- }
- //如果遇到'\0',那么数据会被截断,实际数据全部读取只是没有显示完全,这个时候使用memcpy才能全部获取
- unsigned char* RXBuff = new unsigned char[comstat.cbInQue+1];
- if(RXBuff == NULL)
- {
- return;
- }
- RXBuff[comstat.cbInQue] = '\0';//附加字符串结束符
- EnterCriticalSection(&port->m_csCommunicationSync);
- if (bRead)
- {
- ///串口读出,读出缓冲区中字节
- bResult = ReadFile(port->m_hComm, // Handle to COMM port
- RXBuff, // RX Buffer Pointer
- comstat.cbInQue, // Read cbInQue len byte
- &BytesRead, // Stores number of bytes read
- &port->m_ov); // pointer to the m_ov structure
- // deal with the error code
- ///若返回错误,错误处理
- if (!bResult)
- {
- switch (dwError = GetLastError())
- {
- case ERROR_IO_PENDING:
- {
- // asynchronous i/o is still in progress
- // Proceed on to GetOverlappedResults();
- ///异步IO仍在进行
- bRead = FALSE;
- break;
- }
- case ERROR_ACCESS_DENIED:///拒绝访问 erroe code:5
- {
- port->m_hComm = INVALID_HANDLE_VALUE;
- CString str;
- str.Format("COM%d ERROR_ACCESS_DENIED,ReadFile() Error Code:%d",port->m_nPortNr,GetLastError());
- AfxMessageBox(str);
- break;
- }
- case ERROR_INVALID_HANDLE:///打开串口失败 erroe code:6
- {
- port->m_hComm = INVALID_HANDLE_VALUE;
- break;
- }
- case ERROR_BAD_COMMAND:///连接过程中非法断开 erroe code:22
- {
- port->m_hComm = INVALID_HANDLE_VALUE;
- CString str;
- str.Format("COM%d ERROR_BAD_COMMAND,ReadFile() Error Code:%d",port->m_nPortNr,GetLastError());
- AfxMessageBox(str);
- break;
- }
- default:
- {
- // Another error has occured. Process this error.
- port->ProcessErrorMessage("ReadFile()");
- break;
- //return;///防止读写数据时,串口非正常断开导致死循环一直执行。add by itas109 2014-01-09 与上面liquanhai添加防死锁的代码差不多
- }
- }
- }
- else///ReadFile返回TRUE
- {
- // ReadFile() returned complete. It is not necessary to call GetOverlappedResults()
- bRead = TRUE;
- }
- } // close if (bRead)
- ///异步IO操作仍在进行,需要调用GetOverlappedResult查询
- 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 some byte was received
- ::SendMessage((port->m_pOwner), WM_COMM_RXSTR, (WPARAM) RXBuff, (LPARAM) port->m_nPortNr);
- //如果只有一个串口收发数据,可以传输读取长度,因为RXBuff中可能包含'\0',ASCII为00
- //::SendMessage((port->m_pOwner), WM_COMM_RXSTR, (WPARAM) RXBuff, BytesRead);
- //释放
- delete[] RXBuff;
- RXBuff = NULL;
- } // 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_s(m_szWriteBuffer,m_nWriteBufferSize,string);
- m_nWriteSize=strlen(string); // add by mrlong
- // 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;
- }
- BOOL CSerialPort::IsOpen()
- {
- return m_hComm != NULL && m_hComm!= INVALID_HANDLE_VALUE;//m_hComm增加INVALID_HANDLE_VALUE的情况 add by itas109 2016-07-29
- }
- void CSerialPort::ClosePort()
- {
- MSG message;
- //增加线程挂起判断,解决由于线程挂起导致串口关闭死锁的问题 add by itas109 2016-06-29
- if(IsThreadSuspend(m_Thread))
- {
- ResumeThread(m_Thread);
- }
- //串口句柄无效 add by itas109 2016-07-29
- if(m_hComm == INVALID_HANDLE_VALUE)
- {
- CloseHandle(m_hComm);
- m_hComm = NULL;
- return;
- }
- do
- {
- SetEvent(m_hShutdownEvent);
- //add by liquanhai 防止死锁 2011-11-06
- if(::PeekMessage(&message,m_pOwner,0,0,PM_REMOVE))
- {
- ::TranslateMessage(&message);
- ::DispatchMessage(&message);
- }
- } while (m_bThreadAlive);
- // if the port is still opened: close it
- if (m_hComm != NULL)
- {
- CloseHandle(m_hComm);
- m_hComm = NULL;
- }
- // Close Handles
- if(m_hShutdownEvent!=NULL)
- {
- ResetEvent(m_hShutdownEvent);
- }
- if(m_ov.hEvent!=NULL)
- {
- ResetEvent(m_ov.hEvent);
- }
- if(m_hWriteEvent!=NULL)
- {
- ResetEvent(m_hWriteEvent);
- //CloseHandle(m_hWriteEvent);//开发者反映,这里会导致多个串口工作时,重新打开串口异常
- }
- if(m_szWriteBuffer != NULL)
- {
- delete [] m_szWriteBuffer;
- m_szWriteBuffer = NULL;
- }
- }
- void CSerialPort::WriteToPort(char* string,int n)
- {
- assert(m_hComm != 0);
- memset(m_szWriteBuffer, 0, sizeof(m_szWriteBuffer));
- memcpy(m_szWriteBuffer, string, n);
- m_nWriteSize = n;
- // set event for write
- SetEvent(m_hWriteEvent);
- }
- void CSerialPort::WriteToPort(LPCTSTR string)
- {
- assert(m_hComm != 0);
- memset(m_szWriteBuffer, 0, sizeof(m_szWriteBuffer));
- strcpy_s(m_szWriteBuffer,m_nWriteBufferSize,string);
- m_nWriteSize=strlen(string);
- // set event for write
- SetEvent(m_hWriteEvent);
- }
- void CSerialPort::WriteToPort(BYTE* Buffer, int n)
- {
- assert(m_hComm != 0);
- memset(m_szWriteBuffer, 0, sizeof(m_szWriteBuffer));
- int i;
- for(i=0; i<n; i++)
- {
- m_szWriteBuffer[i] = Buffer[i];
- }
- m_nWriteSize=n;
- // set event for write
- SetEvent(m_hWriteEvent);
- }
- //void CSerialPort::SendData(LPCTSTR lpszData, const int nLength)
- //{
- // assert(m_hComm != 0);
- // memset(m_szWriteBuffer, 0, nLength);
- // strcpy_s(m_szWriteBuffer,m_nWriteBufferSize,lpszData);
- // m_nWriteSize=nLength;
- // // set event for write
- // SetEvent(m_hWriteEvent);
- //}
- //BOOL CSerialPort::RecvData(LPTSTR lpszData, const int nSize)
- //{
- // //
- // //接收数据
- // //
- // assert(m_hComm!=0);
- // memset(lpszData,0,nSize);
- // DWORD mylen = 0;
- // DWORD mylen2 = 0;
- // while (mylen < (DWORD)nSize) {
- // if(!ReadFile(m_hComm,lpszData,nSize,&mylen2,NULL))
- // return FALSE;
- // mylen += mylen2;
- // }
- //
- // return TRUE;
- //}
- //
- ///查询注册表的串口号,将值存于数组中
- ///本代码参考于mingojiang的获取串口逻辑名代码
- //
- void CSerialPort::QueryKey(HKEY hKey)
- {
- #define MAX_KEY_LENGTH 255
- #define MAX_VALUE_NAME 16383
- // TCHAR achKey[MAX_KEY_LENGTH]; // buffer for subkey name
- // DWORD cbName; // size of name string
- TCHAR achClass[MAX_PATH] = TEXT(""); // buffer for class name
- DWORD cchClassName = MAX_PATH; // size of class string
- DWORD cSubKeys=0; // number of subkeys
- DWORD cbMaxSubKey; // longest subkey size
- DWORD cchMaxClass; // longest class string
- DWORD cValues; // number of values for key
- DWORD cchMaxValue; // longest value name
- DWORD cbMaxValueData; // longest value data
- DWORD cbSecurityDescriptor; // size of security descriptor
- FILETIME ftLastWriteTime; // last write time
- DWORD i, retCode;
- TCHAR achValue[MAX_VALUE_NAME];
- DWORD cchValue = MAX_VALUE_NAME;
- // Get the class name and the value count.
- retCode = RegQueryInfoKey(
- hKey, // key handle
- achClass, // buffer for class name
- &cchClassName, // size of class string
- NULL, // reserved
- &cSubKeys, // number of subkeys
- &cbMaxSubKey, // longest subkey size
- &cchMaxClass, // longest class string
- &cValues, // number of values for this key
- &cchMaxValue, // longest value name
- &cbMaxValueData, // longest value data
- &cbSecurityDescriptor, // security descriptor
- &ftLastWriteTime); // last write time
- for (i=0;i<20;i++)///存放串口号的数组初始化
- {
- m_nComArray[i] = -1;
- }
- // Enumerate the key values.
- if (cValues > 0) {
- for (i=0, retCode=ERROR_SUCCESS; i<cValues; i++)
- {
- cchValue = MAX_VALUE_NAME;
- achValue[0] = '\0';
- if (ERROR_SUCCESS == RegEnumValue(hKey, i, achValue, &cchValue, NULL, NULL, NULL, NULL))
- {
- BYTE strDSName[10];
- memset(strDSName, 0, 10);
- DWORD nValueType = 0, nBuffLen = 10;
- if (ERROR_SUCCESS == RegQueryValueEx(hKey, (LPCTSTR)achValue, NULL, &nValueType, strDSName, &nBuffLen))
- {
- int nIndex = -1;
- while(++nIndex < MaxSerialPortNum)
- {
- if (-1 == m_nComArray[nIndex])
- {
- m_nComArray[nIndex] = atoi((char*)(strDSName + 3));
- break;
- }
- }
- }
- }
- }
- }
- else{
- AfxMessageBox(_T("本机没有串口....."));
- }
- }
- void CSerialPort::Hkey2ComboBox(CComboBox& m_PortNO)
- {
- HKEY hTestKey;
- bool Flag = FALSE;
- ///仅是XP系统的注册表位置,其他系统根据实际情况做修改
- if(ERROR_SUCCESS == RegOpenKeyEx(HKEY_LOCAL_MACHINE, TEXT("HARDWARE\\DEVICEMAP\\SERIALCOMM"), 0, KEY_READ, &hTestKey) )
- {
- QueryKey(hTestKey);
- }
- RegCloseKey(hTestKey);
- int i = 0;
- m_PortNO.ResetContent();///刷新时,清空下拉列表内容
- while(i < MaxSerialPortNum && -1 != m_nComArray[i])
- {
- CString szCom;
- szCom.Format(_T("COM%d"), m_nComArray[i]);
- m_PortNO.InsertString(i, szCom.GetBuffer(5));
- ++i;
- Flag = TRUE;
- if (Flag)///把第一个发现的串口设为下拉列表的默认值
- m_PortNO.SetCurSel(0);
- }
- }
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