Visual C++ (MFC)

In VC, the event message routine has the following format.

LRESULT CAioDlg::DefWindowProc(UINT message, WPARAM wParam, LPARAM lParam)

message
The message number is passed.

wParam
The ID is passed to the lower 2 bytes. The upper two bytes are not currently used.

lParam
Parameters specific to each event are passed.

Message Processing Example 1
If there is only one device that uses the event, the device's decision by ID is not particularly necessary. The following code shows an example of displaying a message box when an event occurs.

switch( message ){
case AIOM_AOE_START :
    AfxMessageBox("Generating start", MB_OK, 0);
    break;
case AIOM_AOE_RPTEND :
    AfxMessageBox("Repeat end", MB_OK, 0);
    break;
case AIOM_AOE_END :
    AfxMessageBox("Generating end", MB_OK, 0);
    break;
case AIOM_AOE_DATA_NUM :
    AfxMessageBox("Data stored", MB_OK, 0);
    break;
case AIOM_AOE_SCERR :
    AfxMessageBox("Generating clock period error", MB_OK, 0);
    break;
case AIOM_AOE_ADERR :
    AfxMessageBox("DA conversion error", MB_OK, 0);
    break;
}

Message Processing Example 2
When using events on multiple devices, you need to decide which device generated event. The following code is an example of using events on two devices (ID1 and ID2).

if ( wParam = ID1 ){
    switch( message ){
    case AIOM_AOE_START :
        AfxMessageBox("ID1 : Generating start", MB_OK, 0);
        break;
    case AIOM_AOE_RPTEND :
        AfxMessageBox("ID1 : Repeat end", MB_OK, 0);
        break;
    case AIOM_AOE_END :
        AfxMessageBox("ID1 : Generating end", MB_OK, 0);
        break;
    case AIOM_AOE_DATA_NUM :
        AfxMessageBox("ID1 : Data stored", MB_OK, 0);
        break;
    case AIOM_AOE_SCERR :
        AfxMessageBox("ID1 : Generating clock period error", MB_OK, 0);
        break;
    case AIOM_AOE_ADERR :
        AfxMessageBox("ID1 : DA conversion error", MB_OK, 0);
        break;
    }
}
else{
    switch( message ){
    case AIOM_AOE_START :
        AfxMessageBox("ID2 :Generating start", MB_OK, 0);
        break;
    case AIOM_AOE_RPTEND :
        AfxMessageBox("ID2 :Repeat end", MB_OK, 0);
        break;
    case AIOM_AOE_END :
        AfxMessageBox("ID2 :Generating end", MB_OK, 0);
        break;
    case AIOM_AOE_DATA_NUM :
        AfxMessageBox("ID2 :Data stored", MB_OK, 0);
        break;
    case AIOM_AOE_SCERR :
        AfxMessageBox("ID2 :Generating clock period error", MB_OK, 0);
        break;
    case AIOM_AOE_ADERR :
        AfxMessageBox("ID2 :DA conversion error", MB_OK, 0);
        break;
    }
}