06-19-2012 03:39 PM
I am developing a custom LabVIEW GUI, and I want to have a large Pass/Fail LED indicator that reflects the current pass/fail state of the test as the sequence executes. My test application is a Burn-In that takes 8-hours. It would latch to red on the first step that fails. I notice there is a RunState.Root.SequenceFailed boolean in TestStand, but I don't know how to get at it from LabVIEW, or if there is some other, better way. This should be easy!
Thanks
Solved! Go to Solution.
06-19-2012 03:44 PM
Is your GUI going to be a step that runs asynchronously from the test (i.e. in a different thread)? Or is this GUI customizing the existing UI that ships with TestStand?
If you are customizing the UI that ships with TestStand then you would use UI Messages.
If it is a step then you would pass the sequence context into the GUI as a parameter and use the TestStand Get Property VI.
Hope this helps. Let me know if you need further clarification on one or the other.
06-19-2012 03:59 PM
My GUI is loosely based on the UI that ships with TestStand, so it is using the API and I don't know how to fish out the sequence context once the test is started. What UI Message to I monitor and do I need to perform any special setup beforehand? Thanks for the quick reply.
06-19-2012 04:21 PM
Here is a quick white paper on UI messages: http://www.ni.com/white-paper/4532/en#toc4
You will create your own UI Message number to monitor. The white paper talks about which numbers are valid to use for that.
In my SequencePostStepFailure engine callback is where I would send the UI Message. In fact you wouldn't even need to send the Sequence Context. You could send a True boolean value to the UI and light up the LED. Because if you are in that callback you know a failure occured.
There was an example somewhere out there on how to handle these in the UI. You could possibly google around for it. I know that for sure in the TestStand courses they have you build it into a custom UI. The white paper touches on it.
Hope this helps,
06-19-2012 04:44 PM
OK, I am really close, I think I've almost got it, but I have one last question prompted by your last reply. Where can I access "SequencePostStepFailure" engine callback? I can see "SequenceFilePostStep" but this is not the same I think (?).
06-19-2012 05:05 PM
The callback name is "SequenceFilePostStepFailure", and it works perfectly. Thanks a ton!
06-19-2012 05:34 PM
Oops... I had mistyped it. Sorry. Glad it's working.