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I added VI wrappers with error terminals for Wait (ms), Wait Until Next ms Multiple, and Tick Count in LV 2011. Look for them in vi.lib\Utility\timing. They're not the ideal solution, but until we get error terminals on the primitives, at least we can stop having to worry about maintaining our own copies. -D

Back in the day when I was starting my first real time application, I did run some tests between user events vs queues. The trace execution toolkit was my close friend back in the day. I was worried that user events were a shared resource but it turns out they are fine to use in a RT application especially for triggering. However, there was one major drawback to user events, priority. If I remember correctly, you can not interrupt an event structure with another event structure (i.e. two different event structures). So, a higher priority event could not run until the lower priority event structure was finished. I ended up using single element RT queues and timed structures. But I still use user events quite a bit for sending triggers with data to other low priority threads. User events are very good performance wise in RT applications. David

One thought/comment. You can set a queue size when you create it. If you fill it and then empty it, you can control your message queue size and performance. Is there a technique to monitor / control the size of the user event queue? Could you experience a run-away condition where the system might run out of RAM? An RT based system in my mind should manage memory allocation carefully...