Determine the message content and the device, and add processing according to the message content, are necessary in the event message routine. About skeleton creation of the event message routine, please refer to the tutorial Use Event.
The following parameters are passed to the event message routine.
Message ID
For all event notifications used by API-AIO, the content of the event is determined
by the Message ID. The range of Message
ID used by API-AIO is 1000H
to 10FFH, it has 256 Message
IDs. The Message ID corresponding
to the event related to the counter is as follows.
Message factor of counter |
Macro |
Value |
Comparison count match event |
AIOM_CNTE_DATA_NUM |
1042H |
Count overrun event |
AIOM_CNTE_ORERR |
1043H |
Count operation error event |
AIOM_CNTE_ERR |
1044H |
ID
The ID retrieved by function AioInit is
passed. This ID is used to determine from which device event notification
is sent when using event on multiple devices.
Counter channel number
When more than one counter is used, the counter is identified by the counter
channel number.
The way to pass those parameters is different by the language used.
Visual Basic .NET
Visual C#
Visual C++ (MFC)