WinCE里面都是通过标准的系统API对串口进行操作的,但是串口不同于其它文件,它是是独占式地操作的。
下面是一个操作的串口类:
#pragma once typedef void (*LPDataArriveProc)(char *data,int length,DWORD userdata); // 定义数据处理回调函数(指针类型) class CPSerialPort { public: CPSerialPort(); virtual ~CPSerialPort(); //打开串口 BOOL OpenPort(LPCTSTR Port,); //关闭串口 BOOL ClosePort(); //激活与关闭持续接收 BOOL Activate(); BOOL Deactivate(); BOOL IsActive(); //接收数据线程函数 static DWORD WINAPI ReadPortThread(LPVOID lpParameter); DWORD ReadPort(char *data,int length); //读取一定长度的数据 DWORD WritePort(unsigned char *data,int length); //发送数据 DWORD WriteFileToPort(LPCTSTR FileName); //发送文件 private: HANDLE m_hComm; //串口设备handle HANDLE m_hReadThread; //读串口线程handle BOOL m_bReceiving; //是否持续接收 int m_nBufferSize; //缓冲大小 char *Buffer; //缓冲区 LPDataArriveProc m_lpDataArriveProc; //回调函数,用于处理数据 DWORD m_dwUserData; //串口设置以及超时参数 DCB dcb; COMMTIMEOUTS CommTimeOuts; protected: void ReceiveChar(CPSerialPort *port,COMSTAT comstat); };
#include "StdAfx.h" #include "PSerialPort.h" CPSerialPort::CPSerialPort() { m_hComm = INVALID_HANDLE_VALUE; m_hReadThread = NULL; m_bReceiving = FALSE; m_nBufferSize = ; //缓冲大小 } CPSerialPort::~CPSerialPort() { ClosePort(); } //串口接收线程,主要是中断处理,调用另外一个专门的接收函数实现 DWORD WINAPI CPSerialPort::ReadPortThread(LPVOID lpParameter) //参数指向串口类 { DWORD evtMask; //事件驱动变量WaitCommEvent()用 DWORD dwReadErrrors; //保存出错状态用 COMSTAT cmState; CPSerialPort* m_pSerial; m_pSerial =(CPSerialPort*)lpParameter; if(m_pSerial->m_hComm!=INVALID_HANDLE_VALUE) { PurgeComm(m_pSerial->m_hComm, PURGE_RXCLEAR | PURGE_TXCLEAR ); //清空串口驱动的发送和接收区,此函数一般用在第一次打开串口或长时间未用串口时 SetCommMask (m_pSerial->m_hComm, EV_RXCHAR); //设置响应事件//EV_RXCHAR:输入缓冲区中已收到数据 } while((m_pSerial->m_hComm!=INVALID_HANDLE_VALUE)&&(m_pSerial->m_bReceiving)) { if(WaitCommEvent(m_pSerial->m_hComm,&evtMask,NULL)) //等接收信号 { //有数据 ClearCommError(m_pSerial->m_hComm,&dwReadErrrors,&cmState); //清错误并查询,保证下一次的waitcommEvent(); m_pSerial->ReceiveChar(m_pSerial,cmState); //读数据 } } ; } //读并保存串口数据 void CPSerialPort::ReceiveChar(CPSerialPort *port, COMSTAT comstat) { BOOL bResult = TRUE; DWORD dwError = ; DWORD dwWantRead; BOOL fReadState; DWORD dwLength; char* buf=new char[port->m_nBufferSize]; //生成缓存区 if(!buf) //分配内存失败,返回 return; for(;;) //读数 { bResult=ClearCommError(port->m_hComm,&dwError,&comstat); || !port->m_bReceiving) //无数据或按退出则退出程序 { break; //返回 } //确定读数长度 dwWantRead=comstat.cbInQue; if(dwWantRead> (DWORD)(port->m_nBufferSize)) { dwWantRead=port->m_nBufferSize; } fReadState=ReadFile(port->m_hComm,buf,dwWantRead,&dwLength,NULL); if(!fReadState) { //AfxMessageBox(_T("无法从串口读取数据!")); } else { ) { // 回送数据 if(port->m_lpDataArriveProc!=NULL) // 如果处理数据回调函数不为空 { port->m_lpDataArriveProc(buf,dwLength,port->m_dwUserData); // 处理数据 } } } } // 释放内存 if (buf) { delete[] buf; buf = NULL; } } //打开串口 BOOL CPSerialPort::OpenPort(LPCTSTR Port,int BaudRate,int DataBits,int StopBits,int Parity,LPDataArriveProc proc,DWORD userdata) { m_lpDataArriveProc=proc; //接收线程用的回调函数 m_dwUserData=userdata; //用户参数(指向调用OpenPort()的窗口 if(m_hComm==INVALID_HANDLE_VALUE) { m_hComm=CreateFile(Port,GENERIC_READ|GENERIC_WRITE,,,OPEN_EXISTING,,); //打开串口 if(m_hComm==INVALID_HANDLE_VALUE ) { AfxMessageBox(_T("无法打开端口!请检查是否已被占用。")); return FALSE; } GetCommState(m_hComm,&dcb); dcb.BaudRate=BaudRate; dcb.ByteSize=DataBits; dcb.Parity=Parity; dcb.StopBits=StopBits; dcb.fParity=FALSE; dcb.fBinary=TRUE; dcb.fDtrControl=; dcb.fRtsControl=; dcb.fOutX=dcb.fInX=dcb.fTXContinueOnXoff=; // 设置状态参数 SetCommMask(m_hComm,EV_RXCHAR); //设置"接收到一个字符"事件 SetupComm(m_hComm,,); //设置接收,发送缓存大小为16384byte if(!SetCommState(m_hComm,&dcb)) //将设置的参数写入串口 { AfxMessageBox(_T("无法按当前参数配置端口,请检查参数!")); PurgeComm(m_hComm,PURGE_TXCLEAR|PURGE_RXCLEAR); //清除串口发送接收 ClosePort(); //关闭 return FALSE; } //设置超时参数 GetCommTimeouts(m_hComm,&CommTimeOuts); CommTimeOuts.ReadIntervalTimeout=; //查询方式读数时的时间间隔 CommTimeOuts.ReadTotalTimeoutMultiplier=; //读一个字节时的时间超时上限 CommTimeOuts.ReadTotalTimeoutConstant=; //总超时量 CommTimeOuts.WriteTotalTimeoutMultiplier=; CommTimeOuts.WriteTotalTimeoutConstant=; if(!SetCommTimeouts(m_hComm,&CommTimeOuts)) //写入串口 { AfxMessageBox(_T("无法设置超时参数!")); PurgeComm(m_hComm,PURGE_TXCLEAR|PURGE_RXCLEAR); //清除串口发送接收区 ClosePort(); return FALSE; } PurgeComm(m_hComm,PURGE_TXCLEAR|PURGE_RXCLEAR); //清除串口发送接收区 return TRUE; } return FALSE; } BOOL CPSerialPort::ClosePort() { Deactivate(); if(m_hComm!=INVALID_HANDLE_VALUE) { SetCommMask(m_hComm,); //清事件 PurgeComm(m_hComm,PURGE_TXCLEAR|PURGE_RXCLEAR); //清除串口发送接收区 CloseHandle(m_hComm); m_hComm=INVALID_HANDLE_VALUE; return TRUE; } return TRUE; } BOOL CPSerialPort::Activate() { if(m_hComm==INVALID_HANDLE_VALUE) { return FALSE; } if(!m_bReceiving) { //开始接收线程 PurgeComm(m_hComm,PURGE_TXCLEAR|PURGE_RXCLEAR); m_bReceiving=TRUE; m_hReadThread=CreateThread(NULL,,ReadPortThread,,NULL); } if(m_hReadThread!=NULL) { return TRUE; } else { m_bReceiving=FALSE; return FALSE; } //return FALSE; } BOOL CPSerialPort::Deactivate() { if(m_hComm==INVALID_HANDLE_VALUE) { return FALSE; } //停止接收线程 if(m_bReceiving) { m_bReceiving=FALSE; //关串口读数线程 SetCommMask(m_hComm,); //退出等待线程 WaitForSingleObject(m_hReadThread,); CloseHandle(m_hReadThread); m_hReadThread=NULL; return TRUE; } return FALSE; } BOOL CPSerialPort::IsActive() { return m_bReceiving; } DWORD CPSerialPort::WritePort(unsigned char *data,int length) { DWORD fg; COMSTAT cmstat; if(m_hComm==INVALID_HANDLE_VALUE) { ; } ClearCommError(m_hComm,&fg,&cmstat); // 清错并查询状态 BOOL fWriteState; DWORD dwBytesWritten=; fWriteState=WriteFile(m_hComm,data,length*sizeof(char),&dwBytesWritten,NULL); return dwBytesWritten; } DWORD CPSerialPort::ReadPort(char *data,int length) { BOOL fReadState; DWORD dwLength,dwBytesRead; int TimeOutCount; dwBytesRead=; TimeOutCount=; while(m_hComm!=INVALID_HANDLE_VALUE) { char* buf=new char[length]; fReadState=ReadFile(m_hComm,data,length,&dwLength,NULL); if(!fReadState) { break; } else { dwBytesRead+=dwLength; data+=dwLength; } if(dwBytesRead==(DWORD)length) { break; } ) { TimeOutCount=; } else { TimeOutCount++; Sleep(); } ) { break; } } return dwBytesRead; } DWORD CPSerialPort::WriteFileToPort(LPCTSTR FileName) { if(m_hComm==INVALID_HANDLE_VALUE) { ; } CFile cf; BOOL fWriteState; DWORD dwBytesWritten; DWORD dwCharToWrite; dwCharToWrite=; if(!cf.Open(FileName,CFile::modeRead)) { //AfxMessageBox(_T("无法打开Hex文件!")); ; } dwCharToWrite=(DWORD)cf.GetLength(); cf.Seek(,CFile::begin); dwBytesWritten=; ) { char* buf=new char[dwCharToWrite]; cf.Read(buf,dwCharToWrite); fWriteState=WriteFile(m_hComm,buf,dwCharToWrite*sizeof(char),&dwBytesWritten,NULL); if(!fWriteState) { //AfxMessageBox(_T("无法向端口写入数据!")); } if(buf) { delete[] buf; buf = NULL; } } cf.Close(); return dwBytesWritten; }