Step Type not updating properly with LabVIEW

Question

I have a custom steptype that reads the information from the step properties.  I also want this VI to be used as a stand alone.  So I read the sequence context handle to determine if I am running in TS or standalone.  This works fine.  Because it is a stand alone I have a cluster of all the variables the I will need input.  This is where the problems start.  I noticed that when I define the step type in TS that I load the prototype.  I choose to use the default values for the cluster input because I will read the real values inside the VI.  When I "EDIT" (ctrl-E) the step it works fine.  However at runtime I notice that occasionally the default value is used instead of the real data stored in the step type.  I assume there is a race condition for when my variables are loaded.  I assumed that when TS loads the prototype it will load the default values, then my LabVIEW TS properties will read and set the values of my VI.  What I am seeing is that about every other time my LV will read the steps and update the value correctly then other times TS will overwrite the values with the default after I have read them.  Some other wierd fluke I would notice that the variables would be updated in a similar but different named cluster.  This I haven't be able to reliably reproduce.  It is almost as if the references to the controls would get confused and switch to another control temporarily.
One fix that I have done is to not use the default value but pass the actual step value.  See attached pix.  This is tedious because some of my steps are large.  This is not flexible.  Some of my variables I would like to point to different locations, such as a FileGlobal instead of step.XXX.
Has anyone seen this before?  When does LabVIEW actually write the data from TS into the VI?  It appears that I am having a race condition between me updating the variables by reading the step values and when TS is loading the prototype.
I am using LV 7.1 and TS 3.5.
Thanks.
Attachments:
default.jpg ‏120 KB
step.jpg ‏137 KB

Answer 1

Hey Taylored_Solution,
I'd love to try to help you out with this issue you're having, but I'll be honest - I'm finding it a little hard to follow what's going on.
Have you been able to isolate this behavior to only one single VI (the one you're currently working on), or, is this behavior reproducible in multiple VIs? 
I ask because if it's reproducible in multiple VIs (a new VI), would you mind giving me sort of "step-by-step" to follow so that I can try to reproduce and decipher the behavior you're currently seeing?
If it's isolated to the VI you're working on and not easily reproducible, can you create a copy of your VI, remove everything not-pertinent to the behavior you're seeing, and post a very simple example so that other users can take a look and weigh in?
Derrick S.
Product Manager
NI DIAdem
National Instruments