serial.cpp

一个基于WINCE平台的

// Serial.cpp: implementation of the CSerial class.

//

//////////////////////////////////////////////////////////////////////

 

#include "stdafx.h"

#include "Serial.h"

 

#ifdef _DEBUG

#undef THIS_FILE

static char THIS_FILE[]=__FILE__;

#define new DEBUG_NEW

#endif

 

HANDLE hPort;

CString strInChar;

 

//////////////////////////////////////////////////////////////////////

// Construction/Destruction

//////////////////////////////////////////////////////////////////////

 

CSerial::CSerial()

{

 

}

 

CSerial::~CSerial()

{
       if(hPort != INVALID_HANDLE_VALUE)

              ClosePort(hPort);

}

 

BOOL CSerial::OpenPort(LPTSTR lpszPortName)

{

       DWORD dwError,

                dwThreadID;

      

       if(hPort)

       {

              return FALSE;

       }

 

       //打开串口

       hPort = CreateFile (lpszPortName, GENERIC_READ | GENERIC_WRITE,

                                            0, NULL, OPEN_EXISTING,0, NULL);

       //如果打开端口出错, 返回FALSE

       if ( hPort == INVALID_HANDLE_VALUE )

       {

              //不能打开端口

              CString strError;

              strError.Format(_T("Unable to open %s, Error No.=%d"),

                                           lpszPortName, GetLastError());

 

              MessageBox (NULL, strError,      TEXT("Error"), MB_OK);

 

              return FALSE;

       }

 

       //指定端口监测的事件集

       SetCommMask (hPort, EV_RXCHAR);

       //分配设备缓冲区

       SetupComm(hPort,512,512);

       //初始化缓冲区中的信息

       PurgeComm(hPort,PURGE_TXCLEAR|PURGE_RXCLEAR);

 

       //配置串行端口

       if(!InitDCB())

              return FALSE;

 

       //设置端口超时值

       if(!InitCommTimeouts())

              return FALSE;

 

       //设置端口上指定信号的状态

       // SETDTR: 发送DTR (data-terminal-ready)信号

       // SETRTS: 发送RTS (request-to-send)信号

       EscapeCommFunction (hPort, SETDTR);

       EscapeCommFunction (hPort, SETRTS);

 

       //创建一个从串口读取数据的线程

       if (hReadThread = CreateThread(NULL, 0, ReadPortThread, 0, 0,&dwThreadID))
       {
             MessageBox(NULL, TEXT("成功创建线程"),TEXT("OK"), MB_OK);
       }

       else

       {
              //不能创建线程

              MessageBox (NULL, TEXT("Unable to create the read thread"),TEXT("Error"), MB_OK);

              dwError = GetLastError ();

              return FALSE;

       }

 

       m_bConnected=TRUE;

       return TRUE;

}

 

DWORD CSerial::WritePort(TCHAR *buf,DWORD dwCharToWrite)

{

       BOOL fWriteState;

       DWORD dwBytesWritten;

 

       //写入数据

       fWriteState=WriteFile(hPort,buf,dwCharToWrite*sizeof(TCHAR),&dwBytesWritten,NULL);

       if(!fWriteState)

       {

              //不能写数据

              MessageBox(NULL,TEXT("Can't Write String to Comm"),TEXT("Error"),MB_OK);

              dwBytesWritten=0;

       }

 

       return dwBytesWritten;

}

 

DWORD WINAPI ReadPortThread(LPVOID lpvoid)

{

       BOOL fReadState;

       DWORD dwCommModemStatus;

 

       DWORD dwLength;

       COMSTAT ComStat;

       DWORD dwErrorFlags;

 

       while (hPort != INVALID_HANDLE_VALUE)

       {

              //等待串口的事件发生

              WaitCommEvent (hPort, &dwCommModemStatus, 0);

 

              if (dwCommModemStatus & EV_RXCHAR)

              {

                     ClearCommError(hPort,&dwErrorFlags,&ComStat);

                     //cbInQue返回在串行驱动程序输入队列中的字符数

                     dwLength=ComStat.cbInQue;

 

                     if(dwLength>0)

                     {

                            //从串口读取数据

                            TCHAR* buf=new TCHAR[256];

                            fReadState=ReadFile(hPort,buf,dwLength,&dwLength,NULL);

                            if(!fReadState)

                            {

                                   //不能从串口读取数据

                                   MessageBox(NULL,TEXT("Error in read from serial port"),TEXT("Read Error"),MB_OK);

                            }

                            else

                            {
                                   //把数据赋值给全局变量
                                   strInChar=buf;
                            }

                            delete[] buf;
                     }    

              }
              GetCommModemStatus (hPort, &dwCommModemStatus);

       }

 

       return 0;

}

 

BOOL CSerial::ClosePort(HANDLE hCommPort)

{

       if (hCommPort != INVALID_HANDLE_VALUE)

       {

              //设置连接属性为FALSE

              m_bConnected=FALSE;

 

              //结束线程中WaitCommEvent的等待

              SetCommMask(hPort,0);

             

              //阻塞至线程停止

              if(hReadThread)

              {

                     TerminateThread(hReadThread,0);

                     CloseHandle(hReadThread);

              }

             

              //清除端口上指定信号的状态

            //  EscapeCommFunction(hPort,CLRDTR);

           //   EscapeCommFunction(hPort,CLRRTS);

              //清除驱动程序内部的发送和接收队列

              PurgeComm(hPort,PURGE_TXCLEAR|PURGE_RXCLEAR);

 

              //关闭串口

              CloseHandle (hCommPort);

              hCommPort = INVALID_HANDLE_VALUE;

 

              return TRUE;

       }

       else

       {

              return TRUE;

       }

}

 

BOOL CSerial::InitDCB()

{

       DCB PortDCB;

       DWORD dwError;

 

       PortDCB.DCBlength = sizeof (DCB);    

 

       //得到端口的默认设置信息

       GetCommState (hPort, &PortDCB);

 

       //改变DCB结构设置

       PortDCB.BaudRate = 115200;               //波特率

       PortDCB.fBinary = TRUE;                 //Win32不支持非二进制串行传输模式，必须为TRUE

       PortDCB.fParity = TRUE;                 //启用奇偶校验

       PortDCB.fOutxCtsFlow = FALSE;            //串行端口的输出由CTS线控制

       PortDCB.fOutxDsrFlow = FALSE;           //关闭串行端口的DSR流控制

       PortDCB.fDtrControl = DTR_CONTROL_ENABLE;   //启用DTR线

       PortDCB.fDsrSensitivity = FALSE;        //如果设为TRUE将忽略任何输入的字节，除非DSR线被启用

       //PortDCB.fTXContinueOnXoff = TRUE;       //当为TRUE时，如果接收缓冲区已满且驱动程序已传送XOFF字符，将使驱动程序停止传输字符

       PortDCB.fTXContinueOnXoff = FALSE;

       PortDCB.fOutX = FALSE;                  //设为TRUE指定XON/XOFF控制被用于控制串行输出

       PortDCB.fInX = FALSE;                   //设为TRUE指定XON/XOFF控制被用于控制串行输入

       PortDCB.fErrorChar = FALSE;             //WINCE串行驱动程序的默认执行将忽略这个字段

       PortDCB.fNull = FALSE;                  //设为TRUE将使串行驱动程序忽略收到的空字节

       PortDCB.fRtsControl = RTS_CONTROL_ENABLE;   //启用RTS线

       PortDCB.fAbortOnError = FALSE;          //WINCE串行驱动程序的默认执行将忽略这个字段

       PortDCB.ByteSize = 8;                   //每字节的位数

       PortDCB.Parity = NOPARITY;              //无奇偶校验

       PortDCB.StopBits = ONESTOPBIT;          //每字节一位停止位

 

       //根据DCB结构配置端口

       if (!SetCommState (hPort, &PortDCB))

       {

              //不能配置串行端口

              MessageBox (NULL, TEXT("Unable to configure the serial port"),

                                   TEXT("Error"), MB_OK);

              dwError = GetLastError ();

              return FALSE;

       }

 

       return TRUE;

}

 

BOOL CSerial::InitCommTimeouts()

{

       COMMTIMEOUTS CommTimeouts;

       DWORD dwError;

 

       //得到超时参数

       GetCommTimeouts (hPort, &CommTimeouts);

 

       //改变COMMTIMEOUTS结构设置

       CommTimeouts.ReadIntervalTimeout = MAXDWORD; 

       CommTimeouts.ReadTotalTimeoutMultiplier = 0; 

       CommTimeouts.ReadTotalTimeoutConstant = 0;   

       CommTimeouts.WriteTotalTimeoutMultiplier = 10; 

       CommTimeouts.WriteTotalTimeoutConstant = 1000;   

 

       //设置端口超时值

       if (!SetCommTimeouts (hPort, &CommTimeouts))

       {

              //不能设置超时值

              MessageBox (NULL, TEXT("Unable to set the time-out parameters"),

                                   TEXT("Error"), MB_OK);

              dwError = GetLastError ();

              return FALSE;

       }

 

       return TRUE;

}