MFC下对串口的操作以及定时器的调用

最近研究了一下MFC下对串口的操作，测试了一下对设备的读写。

1.打开串口

 1     GetDlgItem(IDC_BUTTON_OPEN)->EnableWindow(FALSE);
 2     m_hComm = CreateFile("COM1",
 3         GENERIC_READ | GENERIC_WRITE,
 4         0,
 5         NULL,
 6         OPEN_EXISTING,
 7         0,
 8         NULL);
 9     if (m_hComm == INVALID_HANDLE_VALUE)
10     {
11         TCHAR szBuf[1024];
12         wsprintf(szBuf,_T("打开COM1失败,代码:%d"),GetLastError());
13         return;
14     }

2.设置串口通讯参数

 1 DCB dcb;
 2     memset(&dcb,0,sizeof(dcb));
 3     if (!::GetCommState(m_hComm,&dcb))
 4     {
 5         return;
 6     }
 7     dcb.BaudRate = 9600;
 8     dcb.fParity = 1;
 9     dcb.Parity = 0;
10     dcb.ByteSize = 8;
11     dcb.StopBits = 0;
12     SetCommState(m_hComm,&dcb);
13
14     if (!::SetupComm(m_hComm,1024,1024))
15     {
16         return;
17     }

3.设定超时

 1                    //设定读超时
 2     m_CommTimeOuts.ReadIntervalTimeout=MAXDWORD;
 3     m_CommTimeOuts.ReadTotalTimeoutMultiplier=0;
 4     m_CommTimeOuts.ReadTotalTimeoutConstant=0;
 5     //在读一次输入缓冲区的内容后读操作就立即返回，
 6     //而不管是否读入了要求的字符。
 7     //设定写超时
 8     m_CommTimeOuts.WriteTotalTimeoutMultiplier=100;
 9     m_CommTimeOuts.WriteTotalTimeoutConstant=500;
10     ::SetCommTimeouts(m_hComm,&(m_CommTimeOuts)); //设置超时
11     ::PurgeComm(m_hComm,PURGE_RXCLEAR | PURGE_TXABORT);

4.开一个线程
 1 m_pScanThread = AfxBeginThread(ScanThreadProc,this);

5.设置定时器

快捷键Ctrl+W在MessageMaps添加消息响应

 1 void CTestDAMDADlg::OnTimer(UINT nIDEvent)
 2 {
 3     // TODO: Add your message handler code here and/or call default
 4     //AfxMessageBox("Begin");
 5     switch (nIDEvent)
 6     {
 7         case TIMER_2:
 8             {
 9                 //AfxMessageBox("Begin");
10                 OnButton2v();
11                 WriteComm(LENID,offlen);
12                 KillTimer(TIMER_2);
13                 SetTimer(TIMER_4,5000,NULL);
14                 break;
15             }
16         case TIMER_4:
17             {
18                 OnButton4v();
19                 WriteComm(LENID,offlen);
20                 KillTimer(TIMER_4);
21                 SetTimer(TIMER_6,5000,NULL);
22                 break;
23             }
24         case TIMER_6:
25             {
26                 OnButton6v();
27                 WriteComm(LENID,offlen);
28                 KillTimer(TIMER_6);
29                 SetTimer(TIMER_8,5000,NULL);
30                 break;
31             }
32
33         case TIMER_8:
34             {
35                 OnButton8v();
36                 WriteComm(LENID,offlen);
37                 KillTimer(TIMER_8);
38                 SetTimer(TIMER_10,5000,NULL);
39                 break;
40             }
41         case TIMER_10:
42             {
43                 OnButton10v();
44                 WriteComm(LENID,offlen);
45                 KillTimer(TIMER_10);
46                 SetTimer(TIMER_2,5000,NULL);
47                 break;
48             }
49
50         default:
51             {
52                 OnButton6v();
53                 WriteComm(LENID,offlen);
54                 KillTimer(TIMER_2);
55                 SetTimer(TIMER_4,5000,NULL);
56                 break;
57             }
58     }
59     CDialog::OnTimer(nIDEvent);
60 }

线程里开启定时器
 1 dlg->SetTimer(TIMER_2,5000,NULL);

6.调用写串口操作

 1 BOOL CTestDAMDADlg::WriteComm(BYTE *lpByte,DWORD dwBytes)
 2 {
 3     DWORD dwBytesWrite = 20;
 4     COMSTAT ComStat;
 5     DWORD dwErrorFlags;
 6     BOOL bWriteStat;
 7     ClearCommError(m_hComm,&(dwErrorFlags),&(ComStat));
 8     bWriteStat = WriteFile(m_hComm,lpByte,dwBytes,
 9                             &dwBytesWrite,NULL);
10     if (!bWriteStat)
11     {
12         return FALSE;
13     }
14     else
15     {
16         return TRUE;
17     }
18 }

读串口操作类似，这样就完成了定时对串口的读写操作，测试通过！

MFC下对串口的操作以及定时器的调用