Omron DeviceNet 3G8F7-DRM21-E, Руководство по эксплуатации

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Explicit Message API Functions
Section 4-6
Return Value TRUE is returned if registration of the notification message was completed
successfully. FALSE is returned if an error occurred such as null values for
both the thread ID and window handle. Detailed error information can be read
with the GetLastError() function.
Description Along with the notification message, notification of the object class ID of the
server request recipient is sent as WPARAM and notification of the reception
request size (in bytes) is sent as LPARAM.
Clearing a Server Notification Message: SCAN_UnRegServerEvtNotifyMessage()
Application Range Open status
Function Clears registration of the notification message for the specified object class
ID.
Call Format BOOL SCAN_UnRegServerEvtNotifyMessage(DWORD Handle , WORD
ClassId ,)
Arguments
Return Value TRUE is returned if registration of the notification message was cleared suc-
cessfully. FALSE is returned if an error occurred. Detailed error information
can be read with the GetLastError() function.
Checking Server Request Events: SCAN_PeekServerEvent()
Application Range Open status
Function Checks whether there is a server request event addressed to the specified
class ID.
Call Format BOOL SCAN_PeekServerEvent(DWORD Handle , WORD ClassId ,)
Arguments
Return Value TRUE is returned if there is a server request event addressed to the specified
class ID; FALSE is returned if an error occurred or there is not. Detailed error
information can be read with the GetLastError() function.
Reading the Server Request Size: SCAN_GetServerEventLength()
Application Range Open status
Function Gets the server request size (in bytes) for the specified object class ID.
Call Format BOOL SCAN_GetServerEventLength(DWORD Handle , WORD ClassId ,
DWORD* Length )
HWND hWnd Specifies the window handle to notify.
(No setting = NULL)
UINT Msg Notification message
Range: W 0x100 to W
0x7FFF
Type Name Contents
Type Name Contents
DWORD Handle Device handle obtained by SCAN_Open()
WORD ClassId Object class ID being cleared
Type Name Contents
DWORD Handle Device handle obtained by SCAN_Open()
WORD ClassId Class ID being checked for event