串口通信问题,CE 5.0 + Evc 4.0 + Sp4 + API

mdlv 2007-11-15 16:59 楼主

我参照Msdn+网上资料写一个串口通信的类。
如下：
// CeSeriapPort.cpp: implementation of the CCeSerialPort class.
//
//////////////////////////////////////////////////////////////////////

#include "stdafx.h"
#include "CeSeriapPort.h"
#include "comport.h"

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

CCeSerialPort::CCeSerialPort()
{
m_bAlive = false;
m_hComm = NULL;
ZeroMemory(m_bReadBuf,sizeof(m_bReadBuf));
}

CCeSerialPort::~CCeSerialPort()
{

}

BOOL CCeSerialPort::OpenPort(UINT uPort, UINT uBaud, BYTE bData, BYTE bStop, BYTE bVerify)
{
WCHAR wszPort[16] = L"";
::wsprintf(wszPort,L"COM%d:",uPort);
DCB dcb;
HANDLE hThread = NULL;

m_hComm = CreateFile(wszPort,GENERIC_READ | GENERIC_WRITE,0,NULL,OPEN_EXISTING,0,NULL);
if(INVALID_HANDLE_VALUE == m_hComm)
{
MessageBox(NULL,L"打开串口失败!",L"错误信息",MB_ICONSTOP);
return FALSE;
}

if(!SetCommMask(m_hComm,EV_RXCHAR | EV_CTS | EV_DSR | EV_RING | EV_RLSD)) //| EV_CTS | EV_DSR | EV_RING | EV_RLSD
{
MessageBox(NULL,L"设置串口事件失败!",L"错误信息",MB_ICONSTOP);
}

SetupComm(m_hComm,256,256);

PurgeComm(m_hComm,PURGE_TXABORT | PURGE_RXABORT | PURGE_TXCLEAR | PURGE_RXCLEAR);

dcb.DCBlength = sizeof(DCB);

if(GetCommState(m_hComm,&dcb))
{
dcb.BaudRate = uBaud;
dcb.ByteSize = bData;
dcb.StopBits = bStop;
dcb.Parity = bVerify;
dcb.fBinary = TRUE;
dcb.fParity = TRUE;
dcb.fOutxCtsFlow = FALSE;
dcb.fOutxDsrFlow = FALSE;
dcb.fDtrControl = DTR_CONTROL_ENABLE;
dcb.fDsrSensitivity = FALSE;
dcb.fTXContinueOnXoff = TRUE;
dcb.fOutX = FALSE;
dcb.fInX = FALSE;
dcb.fErrorChar = FALSE;
dcb.fNull = FALSE;
dcb.fRtsControl = RTS_CONTROL_ENABLE;
dcb.fAbortOnError = FALSE;

if(!SetCommState(m_hComm,&dcb))
{
MessageBox(NULL,L"设置串口属性失败!",L"错误信息",MB_ICONSTOP);
}
}

COMMTIMEOUTS CommTimeouts;
GetCommTimeouts (m_hComm, &CommTimeouts);

// Change the COMMTIMEOUTS structure settings.
CommTimeouts.ReadIntervalTimeout = MAXDWORD;
CommTimeouts.ReadTotalTimeoutMultiplier = 0;
CommTimeouts.ReadTotalTimeoutConstant = 0;
CommTimeouts.WriteTotalTimeoutMultiplier = 10;
CommTimeouts.WriteTotalTimeoutConstant = 1000;

if(!SetCommTimeouts(m_hComm,&CommTimeouts))
{
MessageBox(NULL,L"设置超时参数失败!",L"错误信息",MB_ICONSTOP);
}

m_bAlive = true;

// DWORD dw = 0;
// ReadFile(m_hComm,m_bReadBuf,sizeof(m_bReadBuf),&dw,0);

hThread = CreateThread(NULL,0,ComThreadProc,this,0,NULL);
if(hThread == NULL)
{
m_bAlive = false;
MessageBox(NULL,L"创建监视线程失败!",L"错误信息",MB_ICONSTOP);
CloseHandle(m_hComm);
return FALSE;
}

CloseHandle(hThread);

return TRUE;
}

void CCeSerialPort::ClosePort()
{
if(m_bAlive)
{
m_bAlive = false;
SetCommMask(m_hComm,0);
PurgeComm(m_hComm,PURGE_TXABORT | PURGE_RXABORT | PURGE_TXCLEAR | PURGE_RXCLEAR);
CloseHandle(m_hComm);
m_hComm = NULL;
}
}

DWORD CCeSerialPort::ComThreadProc(LPVOID lParam)
{
CCeSerialPort * pPort = (CCeSerialPort*)lParam;
DWORD dwEvtMask,dwReaded = 0,dwError = 0;
COMSTAT comstat;

SetCommMask(pPort->m_hComm, EV_RXCHAR | EV_CTS | EV_DSR | EV_RLSD | EV_RING);

while(pPort->m_bAlive)
{
WaitCommEvent(pPort->m_hComm,&dwEvtMask,0);

if(pPort->m_bAlive == false) break;

SetCommMask (pPort->m_hComm, EV_RXCHAR | EV_CTS | EV_DSR | EV_RLSD | EV_RING);

if((dwEvtMask & EV_RXCHAR) == EV_RXCHAR)
{
ClearCommError(pPort->m_hComm,&dwError,&comstat);
if(comstat.cbInQue > 0)
{
if(ReadFile(pPort->m_hComm,pPort->m_bReadBuf,MAX_READ_BUFFER,&dwReaded,0) && dwReaded > 0)
{
ShowData(pPort->m_bReadBuf,dwReaded);
ZeroMemory(pPort->m_bReadBuf,dwReaded);
}
}
}
else
{
dwReaded = 0;
if(GetCommModemStatus(pPort->m_hComm,&dwReaded))
{
ChangeState(dwReaded);
}
}
}
return 0;
}

DWORD CCeSerialPort::WriteData(BYTE *pszBuff,DWORD dwWriteBytes)
{
DWORD dwWrited = 0;
if(m_bAlive)
{
if(!WriteFile(m_hComm,(LPCVOID)pszBuff,dwWriteBytes,&dwWrited,0))
{
dwWrited = 0;
}
}

return dwWrited;
}

BOOL CCeSerialPort::SetLineState(DWORD dwState)
{
if(m_bAlive)
{
return EscapeCommFunction(m_hComm,dwState);
}
return FALSE;
}

此类写串口好用，读串口不好用。

阻塞在WaitCommEvent函数，当我发送数据的时候他不响应。程序退出的时候它响应。

另一端为开发机: P D 3.0 + 1G内存 + xp + 串口调试工具 + evc 4.0 + Sp4