freqin.c

16 relay output channels and 16 isolated digital input channels LED indicators to show activated

            case IDOK :

                //
                // get scan time
                //

                if (SendDlgItemMessage(hDlg, IDC_SCAN,
                           EM_GETMODIFY, 0, 0))
                {
                    SendDlgItemMessage(hDlg, IDC_SCAN,
                            WM_GETTEXT, 10, (LPARAM)(LPSTR)szBuffer) ;
                    gwScanTime = atoi(szBuffer);
                    SendDlgItemMessage(hDlg, IDC_SCAN,
                              EM_SETMODIFY, FALSE, 0) ;
                }

            case IDCANCEL :
                EndDialog(hDlg, 0);
                return TRUE;

         }
         break;
    }
    return FALSE ;
}


/***************************************************************************
    FUNCTION: MainWndProc(HWND, unsigned, WPARAM, LPARAM)

    PURPOSE:  Processes messages

    MESSAGES:

        WM_CREATE     - create window
        WM_COMMAND    - application menu (About dialog box)
        WM_DESTROY    - destroy window
****************************************************************************/

long FTYPE MainWndProc
(
    HWND        hWnd,                          // window handle
    unsigned    message,                       // type of message
    WPARAM      wParam,                        // additional information
    LPARAM      lParam                         // additional information
)
{
    static  HANDLE  hInstance ;
    HMENU           hMenu;
    HDC             hdc;
    char            szBuffer[120];
    RECT            rect;
    DWORD           dwCurrentTime;
    DWORD           dwErrorTime;
    BOOL            bTimerOverrun;

    switch (message)
    {
        case WM_CREATE:

            //
            // initialize Stop Menu
            //

            hMenu = GetMenu(hWnd);
            EnableMenuItem(hMenu, IDM_STOP, MF_BYCOMMAND | MF_GRAYED);

            hInstance = ((LPCREATESTRUCT) lParam)->hInstance ;

            lpfnConfigDlgProc = MakeProcInstance (ConfigDlgProc, hInstance) ;

            lpfnScanDlgProc = MakeProcInstance (ScanDlgProc, hInstance) ;
            
            
            return 0 ;

        case WM_COMMAND:     /* message: from application menu */

            hMenu = GetMenu(hWnd);

            switch (LOWORD(wParam))
            {
                case IDM_SETTING :
                    DialogBox (hInstance, MAKEINTRESOURCE(IDD_SETTING),
                         hWnd, lpfnConfigDlgProc) ;
                    return 0;

                case IDM_SCAN :
                    DialogBox (hInstance, MAKEINTRESOURCE(IDD_SCAN),
                         hWnd, lpfnScanDlgProc) ;
                    return 0;

                case IDM_STOP :

                    //
                    // kill timer and close driver
                    //

                    KillTimer(hWnd, 1);
                 
                    //
                    // counter reset
                    //

                    if ((ErrCde = DRV_CounterReset(DriverHandle,
                        (LPARAM)gwChannel)) != 0)
                    {
                        DRV_GetErrorMessage(ErrCde,(LPSTR)szErrMsg);
                        MessageBox(hWnd,(LPCSTR)szErrMsg, "Driver Message", MB_OK);
                    }

                    DRV_DeviceClose((LONG far *)&DriverHandle);

                    bRun = FALSE;

                    //
                    // reset menu item status
                    //

                    EnableMenuItem(hMenu, IDM_STOP, MF_BYCOMMAND | MF_GRAYED);
                    EnableMenuItem(hMenu, IDM_START, MF_BYCOMMAND | MF_ENABLED);

                    return 0;

                case IDM_START :

                    //
                    // Open Device
                    //

                    if (gnNumOfSubdevices == 0)
                        ErrCde = DRV_DeviceOpen(
                            DeviceList[gwDevice].dwDeviceNum,
                                (LONG far *)&DriverHandle);
                    else
                        ErrCde = DRV_DeviceOpen(
                            SubDeviceList[gwSubDevice].dwDeviceNum,
                                (LONG far *)&DriverHandle);

                    if (ErrCde != SUCCESS)
                    {
                        strcpy(szErrMsg,"Device open error !");
                        MessageBox(hWnd,(LPCSTR)szErrMsg,"Device Open",MB_OK);
                        return 0;
                    }


                    //
                    // get number of counter channels
                    //

                    ptDevFeatures.buffer = (LPDEVFEATURES)&DevFeatures;
                    ptDevFeatures.size = sizeof(DEVFEATURES);
                    if ((ErrCde = DRV_DeviceGetFeatures(DriverHandle,
                        (LPT_DeviceGetFeatures)&ptDevFeatures)) != SUCCESS)
                    {
                        DRV_GetErrorMessage(ErrCde,(LPSTR)szErrMsg);
                        MessageBox(hWnd,(LPCSTR)szErrMsg,"Driver Message",MB_OK);
                        DRV_DeviceClose((LONG far *)&DriverHandle);
                        return 0;
                    }

                    // check number of counter channels
                    if (DevFeatures.usMaxTimerChl == 0)
                    {
                        MessageBox(hWnd,(LPCSTR)"No Counter Channel",
                            "Driver Message",MB_OK);
                        DRV_DeviceClose((LONG far *)&DriverHandle);
                        return 0;
                    }


                    //
                    // start counter
                    //

                    ptCounterFreqStart.counter = gwChannel;
                    ptCounterFreqStart.GatePeriod = gwGatePeriod;
                    ptCounterFreqStart.GateMode = gwGateMode;    //no use here

                    if ((ErrCde = DRV_CounterFreqStart(DriverHandle,
                             (LPT_CounterFreqStart)&ptCounterFreqStart)) != 0)
                    {
                        DRV_GetErrorMessage(ErrCde,(LPSTR)szErrMsg);
                        MessageBox(hWnd,(LPCSTR)szErrMsg, "Driver Message", MB_OK);
                        return TRUE;
                    }


                    //
                    // enable Stop Menu item and disable the others
                    //

                    EnableMenuItem(hMenu, IDM_STOP, MF_BYCOMMAND | MF_ENABLED);
                    EnableMenuItem(hMenu, IDM_START, MF_BYCOMMAND | MF_GRAYED);

                    //
                    // Set the new timer type and start it up.
                    //

                    if (SetTimer(hWnd, 1, gwScanTime, NULL) == (UINT)NULL)
                    {
                        MessageBox(hWnd, "Couldn't create timer.", "Notice!",
                            MB_OK);
                        DRV_DeviceClose((LONG far *)&DriverHandle);
                        return 0;
                    }

                   //create thread
                    bRun = TRUE;         
                    gdwStartTime = GetTickCount();
                    gwOverrunCount = 0;

                    return 0;
            }
            return 0;

        case WM_TIMER:

            //
            // Timer set to dispatch a WM_TIMER message has gone off.
            //

            //
            // check if timer is overrun
            //

            dwCurrentTime = GetTickCount();

            gdwElapseTime = gdwElapseTime + (DWORD)gwScanTime;
            dwErrorTime = dwCurrentTime - gdwElapseTime - gdwStartTime;
            if (dwErrorTime > (DWORD)40)        // maximum 40 ms scan time
            {
                gdwElapseTime = dwCurrentTime - gdwStartTime;
                gwOverrunCount ++;
                if (gwOverrunCount >= 10)
                {
                    bTimerOverrun = TRUE;
                    gwOverrunCount = 0;
                }
                else
                    bTimerOverrun = FALSE;
            }
            else
            {
                bTimerOverrun = FALSE;
                gwOverrunCount = 0;
            }


           //
           // read freqency
           //
            
            ptCounterFreqRead.counter = gwChannel;
            ptCounterFreqRead.freq = &gfFreq;
            if ((ErrCde = DRV_CounterFreqRead(DriverHandle,
                       (LPT_CounterFreqRead)&ptCounterFreqRead)) != 0)
            {
                 DRV_GetErrorMessage(ErrCde,(LPSTR)szErrMsg);
                 MessageBox(hWnd,(LPCSTR)szErrMsg, "Driver Message", MB_OK);
                 return TRUE;
            }

            //
            // Display Data
            //
            hdc = GetDC(hWnd);
            GetClientRect(hWnd, &rect);
            InvalidateRect(hWnd, NULL, TRUE);
            UpdateWindow(hWnd);
            sprintf(szBuffer, "Frequency Reading =  %f Hz", *(ptCounterFreqRead.freq));
            DrawText(hdc, szBuffer, -1, &rect,DT_SINGLELINE | DT_CENTER | DT_VCENTER);
            
           
            ReleaseDC(hWnd, hdc);
            

            return 0;

        case WM_DESTROY:
            if (bRun == TRUE)
            {
                              
               KillTimer(hWnd, 1);

                // counter reset
                if( (ErrCde = DRV_CounterReset(DriverHandle,
                    (LPARAM)gwChannel)) != 0)
                {
                    DRV_GetErrorMessage(ErrCde,(LPSTR)szErrMsg);
                    MessageBox(hWnd,(LPCSTR)szErrMsg, "Driver Message", MB_OK);
                }

                DRV_DeviceClose((LONG far *)&DriverHandle);
            }
            PostQuitMessage(0);
            break;

        default:
            return (DefWindowProc(hWnd, message, wParam, lParam));
    }

    return ((LONG)NULL);
}