DAQmxRegisterSignalEvent Unregister

[JVL]

Is there a way to unregister a signal event once the event no longer needs to be detected. I am assuming that this can be done by using a NULL as the callback function pointer but the document is silent on the matter. The other thing that I can think of is to set the signal id to NULL but that may correspond with one of the defined signal types.

Thanks,

John

[Tom_W_[DE]]

Hi John-

Yes- passing a NULL value to the callback function pointer will be sufficient to unregister the event.  You should leave the signal id specified so that the NULL callback function pointer will be properly applied to the event associated with that function.  You may also notice that unregistering (or even changing the registration) of an event is not allowed at runtime; you must stop the task to make any changes to the event registrations.

Hopefully this helps-

Message Edited by Tom W [DE] on 02-09-2006 02:57 PM