serialport.cpp

51isp下载软件,使用非常方便。非常适应初学者制作使用

	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;
}

///////////////////////////////////////////////////////////////////
//增加4个函数方便收发数据块
//SendBlock(BYTE *pBuf, unsigned long nLength):发送数据块
//virtual OnReceived(BYTE *pBuf, UINT nLength):当接受到指定长度的数据块时
//默认函数将发送消息给窗口
//SetExpRcv(nLength):设定接收数据块的长度

unsigned long CSerialPort::SendBlock(BYTE *pBuf, unsigned long nLength)
{
	
	BOOL bWrite = TRUE;
	BOOL bResult = TRUE;
	unsigned long nBytesSent=0;
	DWORD BytesSent = 0;
	ResetEvent(this->m_hWriteEvent);

	// Gain ownership of the critical section
	EnterCriticalSection(&this->m_csCommunicationSync);

	if (bWrite)
	{
		// Initailize variables
		this->m_ov.Offset = 0;
		this->m_ov.OffsetHigh = 0;

		// Clear buffer
		PurgeComm(this->m_hComm, PURGE_RXCLEAR | PURGE_TXCLEAR | PURGE_RXABORT | PURGE_TXABORT);

		bResult = WriteFile(this->m_hComm,	// Handle to COMM Port
							pBuf,	// Pointer to message buffer in calling finction
							nLength,	// Length of message to send
							&nBytesSent,	// Where to store the number of bytes sent
							&this->m_ov);	// Overlapped structure

		// deal with any error codes
		if (!bResult)  
		{
			DWORD dwError = GetLastError();
			switch (dwError)
			{
				case ERROR_IO_PENDING:
					{
						// continue to GetOverlappedResults()
						nBytesSent = 0;
						bWrite = FALSE;
						break;
					}
				default:
					{
						// all other error codes
						this->ProcessErrorMessage("WriteFile()");
					}
			}
		} 
		else
		{
			LeaveCriticalSection(&this->m_csCommunicationSync);
		}
	} // end if(bWrite)

	if (!bWrite)
	{
		bWrite = TRUE;
	
		bResult = GetOverlappedResult(this->m_hComm,	// Handle to COMM port 
									  &this->m_ov,		// Overlapped structure
									  &nBytesSent,		// Stores number of bytes sent
									  TRUE); 			// Wait flag

		LeaveCriticalSection(&this->m_csCommunicationSync);

		// deal with the error code 
		if (!bResult)  
		{
			this->ProcessErrorMessage("GetOverlappedResults() in WriteFile()");
		}	
	} // end if (!bWrite)

	// Verify that the data size send equals what we tried to send
	if (nBytesSent != nLength)
	{
		TRACE("WARNING: WriteFile() error.. Bytes Sent: %d; Message Length: %d\n", BytesSent, strlen((char*)this->m_szWriteBuffer));
	}
	TRACE("Byts Sent:%d\n",nBytesSent);
	return	nBytesSent;
}

void CSerialPort::ReceiveBlock(COMSTAT comstat)
{
	BOOL  bRead = TRUE; 
	BOOL  bResult = TRUE;
	DWORD dwError = 0;
	DWORD nBytesRcv = 0;
	for (;;) 
	{ 
		// Gain ownership of the comm port critical section.
		// This process guarantees no other part of this program 
		// is using the port object. 
		EnterCriticalSection(&this->m_csCommunicationSync);

		// ClearCommError() will update the COMSTAT structure and
		// clear any other errors.
		bResult = ClearCommError(this->m_hComm, &dwError, &comstat);
		LeaveCriticalSection(&this->m_csCommunicationSync);
		if (comstat.cbInQue == 0)
		{
			// break out when all bytes have been read
			break;
		}
		EnterCriticalSection(&this->m_csCommunicationSync);
		if (bRead)
		{
			bResult = ReadFile(this->m_hComm,		// Handle to COMM port 
							   RxdBuf,				// RX Buffer Pointer
							   m_nBytesExpected,	// Read one byte
							   &nBytesRcv,			// Stores number of bytes read
							   &this->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.
							this->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(this->m_hComm,	// Handle to COMM port 
										  &this->m_ov,		// Overlapped structure
										  &nBytesRcv,		// Stores number of bytes read
										  TRUE); 			// Wait flag

			// deal with the error code 
			if (!bResult)  
			{
				this->ProcessErrorMessage("GetOverlappedResults() in ReadFile()");
			}	
		}  // close if (!bRead)
				
		LeaveCriticalSection(&this->m_csCommunicationSync);

		// notify parent that a byte was received
		 OnReceived ((BYTE*)RxdBuf, nBytesRcv);
	} // end forever loop
}

void CSerialPort::OnReceived(BYTE *pBuf, UINT nLength)
{
	::PostMessage((this->m_pOwner)->m_hWnd, WM_COMM_RXD, (WPARAM)pBuf, (LPARAM)nLength);
}

void CSerialPort::SetExpRcv(UINT nLength)
{
	m_nBytesExpected=nLength;
	if(RxdBuf==NULL)
	{
		RxdBuf=new BYTE[nLength+128];
	}
	else
	{
		delete	RxdBuf;
		RxdBuf=new BYTE[nLength+128];
	}
}