一个支持同步异步的串口类

#include "stdafx.h" #include "ComPort.h" CComPort::CComPort() :m_bOverlapped(FALSE), m_hComm(INVALID_HANDLE_VALUE) { ZeroMemory(&m_ReadOverlapped, sizeof(OVERLAPPED)); ZeroMemory(&m_WriteOverlapped, sizeof(OVERLAPPED)); ZeroMemory(&m_WriteOverlapped, sizeof(OVERLAPPED)); m_pReadComThread = new CReadComThread(this); } CComPort::~CComPort() { Close(); delete m_pReadComThread; } /************************************************************************ 打开串口 ************************************************************************/ BOOL CComPort::Open(int nPort, BOOL bOverlapped /*=FALSE*/, DWORD dwBaud /*= 9600*/, BYTE DataBits /*= 8*/, CComPort::Parity parity /*= NoParity*/, CComPort::StopBits stopbits /*= OneStopBit*/, CComPort::FlowControl fc /*= NoFlowControl*/) { ASSERT(nPort>0 && nPort<=255); CString strPort; strPort.Format(_T("\\\\.\\COM%d"), nPort); DWORD dwFlags; if (bOverlapped) { dwFlags = FILE_ATTRIBUTE_NORMAL | FILE_FLAG_OVERLAPPED; } else { dwFlags = FILE_ATTRIBUTE_NORMAL; } m_hComm = CreateFile(strPort, GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, dwFlags, NULL); if (m_hComm == INVALID_HANDLE_VALUE) { return FALSE; } //Get the current state prior to changing it DCB dcb; dcb.DCBlength = sizeof(DCB); GetCommState(m_hComm, &dcb); //Setup the baud rate dcb.BaudRate = dwBaud; //Setup the Parity switch (parity) { case EvenParity: dcb.Parity = EVENPARITY; break; case MarkParity: dcb.Parity = MARKPARITY; break; case NoParity: dcb.Parity = NOPARITY; break; case OddParity: dcb.Parity = ODDPARITY; break; case SpaceParity: dcb.Parity = SPACEPARITY; break; default: ASSERT(FALSE); break; } //Setup the data bits dcb.ByteSize = DataBits; //Setup the stop bits switch (stopbits) { case OneStopBit: dcb.StopBits = ONESTOPBIT; break; case OnePointFiveStopBits: dcb.StopBits = ONE5STOPBITS; break; case TwoStopBits: dcb.StopBits = TWOSTOPBITS; break; default: ASSERT(FALSE); break; } //Setup the flow control dcb.fDsrSensitivity = FALSE; switch (fc) { case NoFlowControl: { dcb.fOutxCtsFlow = FALSE; dcb.fOutxDsrFlow = FALSE; dcb.fOutX = FALSE; dcb.fInX = FALSE; break; } case CtsRtsFlowControl: { dcb.fOutxCtsFlow = TRUE; dcb.fOutxDsrFlow = FALSE; dcb.fRtsControl = RTS_CONTROL_HANDSHAKE; dcb.fOutX = FALSE; dcb.fInX = FALSE; break; } case CtsDtrFlowControl: { dcb.fOutxCtsFlow = TRUE; dcb.fOutxDsrFlow = FALSE; dcb.fDtrControl = DTR_CONTROL_HANDSHAKE; dcb.fOutX = FALSE; dcb.fInX = FALSE; break; } case DsrRtsFlowControl: { dcb.fOutxCtsFlow = FALSE; dcb.fOutxDsrFlow = TRUE; dcb.fRtsControl = RTS_CONTROL_HANDSHAKE; dcb.fOutX = FALSE; dcb.fInX = FALSE; break; } case DsrDtrFlowControl: { dcb.fOutxCtsFlow = FALSE; dcb.fOutxDsrFlow = TRUE; dcb.fDtrControl = DTR_CONTROL_HANDSHAKE; dcb.fOutX = FALSE; dcb.fInX = FALSE; break; } case XonXoffFlowControl: { dcb.fOutxCtsFlow = FALSE; dcb.fOutxDsrFlow = FALSE; dcb.fOutX = TRUE; dcb.fInX = TRUE; dcb.XonChar = 0x11; dcb.XoffChar = 0x13; dcb.XoffLim = 100; dcb.XonLim = 100; break; } default: { ASSERT(FALSE); break; } } //Now that we have all the settings in place, make the changes SetCommState(m_hComm, &dcb); SetBufferSize(1024, 1024); PurgeComm(m_hComm, PURGE_TXABORT|PURGE_RXABORT|PURGE_TXCLEAR|PURGE_RXCLEAR); COMMTIMEOUTS timeouts; GetTimeouts(timeouts); timeouts.ReadIntervalTimeout = 100; SetTimeouts(timeouts); m_bOverlapped = bOverlapped; if (m_bOverlapped) { m_ReadOverlapped.hEvent = CreateEvent(NULL, FALSE, FALSE, NULL); m_WriteOverlapped.hEvent = CreateEvent(NULL, FALSE, FALSE, NULL); m_WaitOverlapped.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL); } m_pReadComThread->Create(); return TRUE; } /************************************************************************ 关闭串口 ************************************************************************/ void CComPort::Close() { if (IsOpen()) { if (m_pReadComThread) { m_pReadComThread->Exit(); } CloseHandle(m_hComm); m_hComm = INVALID_HANDLE_VALUE; m_bOverlapped = FALSE; if (m_ReadOverlapped.hEvent) { CloseHandle(m_ReadOverlapped.hEvent); } if (m_WriteOverlapped.hEvent) { CloseHandle(m_WriteOverlapped.hEvent); } if (m_WaitOverlapped.hEvent) { CloseHandle(m_WaitOverlapped.hEvent); } } } void CComPort::SetTimeouts(COMMTIMEOUTS& timeouts) { ASSERT(IsOpen()); if (!SetCommTimeouts(m_hComm, &timeouts)) { TRACE(_T("Failed in call to SetCommTimeouts\n")); } } void CComPort::GetTimeouts(COMMTIMEOUTS& timeouts) { ASSERT(IsOpen()); if (!GetCommTimeouts(m_hComm, &timeouts)) { TRACE(_T("Failed in call to GetCommTimeouts\n")); } } /************************************************************************ 串口是否打开 ************************************************************************/ BOOL CComPort::IsOpen() const { return m_hComm != INVALID_HANDLE_VALUE; } /************************************************************************ 设置串口输入和输出缓冲区大小 ************************************************************************/ void CComPort::SetBufferSize(DWORD dwInputSize, DWORD dwOutputSize) { ASSERT(IsOpen()); SetupComm(m_hComm, dwInputSize, dwOutputSize); } /************************************************************************ 获取串口输入缓冲区字节数量 ************************************************************************/ DWORD CComPort::GetInputSize() const { COMSTAT Stat; DWORD dwError; return ClearCommError(m_hComm, &dwError, &Stat) == TRUE ? Stat.cbInQue : (DWORD)-1L; } /************************************************************************ 设置事件信号掩码 ************************************************************************/ void CComPort::SetEvent(DWORD dwMask) { ASSERT(IsOpen()); SetCommMask(m_hComm, dwMask); } /************************************************************************ 支持同步,异步模式 ************************************************************************/ BOOL CComPort::WaitEvent(DWORD &dwMask) { ASSERT(IsOpen()); LPOVERLAPPED pWait = NULL; if (m_bOverlapped) { pWait = &m_WaitOverlapped; } if (!WaitCommEvent(m_hComm, &dwMask, pWait)) { if (pWait) { if (GetLastError()== ERROR_IO_PENDING) { DWORD dwLength; return GetOverlappedResult(m_hComm, &m_WaitOverlapped, &dwLength, TRUE); } else { return FALSE; } } else { return FALSE; } } return TRUE; } /************************************************************************ 从串口读数据， 可设定超时 当为同步模式时，忽略超时；异步模式时，超时有效 ************************************************************************/ DWORD CComPort::ReadComm(void* pData, DWORD dwDataSize, DWORD dwTimeouts /* = 0 */) { ASSERT(pData); ASSERT(IsOpen()); COMSTAT Stat; DWORD dwError; if(::ClearCommError(m_hComm, &dwError, &Stat) && dwError > 0) { ::PurgeComm(m_hComm, PURGE_RXABORT | PURGE_RXCLEAR); return 0; } // 缓冲区无数据 if(!Stat.cbInQue) return 0; DWORD dwReadBytes = 0; LPOVERLAPPED pOver = NULL; //异步读取数据 if (m_bOverlapped) { pOver = &m_ReadOverlapped; } dwDataSize = min(Stat.cbInQue, dwDataSize); if (!ReadFile(m_hComm, pData, dwDataSize, &dwReadBytes, pOver)) { if (pOver) { if (ERROR_IO_PENDING == GetLastError()) { WaitForSingleObject(m_ReadOverlapped.hEvent, dwTimeouts); /