Whey does asynchronous output initiated with WFM_Group_Control() sometimes stop without any indication of it?

[JackMetcalfe]

In a Visual C++ program one object calls on a method of another object to initiate asynchronous signal generation. On return from the function the signal generation will stop.

I was concerned that the memory provided for outputting levels in the call to WFM_Load was being released on return from the function that initiated the signal generation so ensured that this was not the case.

This does not occur all of the time but has happened and not happened without any change in code. I have checked for memory overruns during execution and none have been found. Once the situation is encountered I have not been able to identify a way to get it to start working
again. Mysteriously this includes cycling power.

The problem does not occur outside of the Visual C++ debugger. The same build when run outside of the debugger runs to completion without a problem. That is the signal generation does not stop on return from the initiating function.

The problem displays itself even when no events have been explicitly registered.

Any sharing of similar experiences or advice is appreciated. If I can't resolve this matter than I will have to resort to MessageBox()/printf/fprintf style of debugging.

Thanks in advance,
Jack

[mrak1]

Since this problem is only occurring when you are using Visual C++, I would venture to say that the problem lies with Visual C++. This is especially evident since the program runs without problem when it is a standalone executable.

I would suggest trying to uninstall and reinstall the Visual Studio development environment. I would also try to see if this problem is occurring on another machine. If it works on the development environment of the other machine, then your other computer may need a software overhaul (reinstall OS and development software).

If you are still having problems with this after trying these suggestions, feel free to contact National Instruments Support at www.ni.com/ask.

Good Luck!

Mike Rakolta
Applications Engineer
Nation
al Instruments
www.ni.com/ask