Data doesn't update in SE from vi

[Evie]

I'm trying to get this example vi file to run in Signal Express.

File: GenerateRandomSignal.vi  from  labview\examples\general\structs.llb, this is an example of using the While Loop.

I followed the proceed for using LV vi's in SE.

The data doesn't update in SE.

Any suggestions?

[Evie]

The Random  Signal display is connected to the Connector Pane in the vi.

The output is shown in SE but it is blank and never updates with information.

[Evie]

I'm having a problem with another vi that has a While Loop i it so I tested this example vi and it doesn't work either.

What we are trying to do is bring in data that is running on a program written in C#.

We are using a DLL to bring the data into a vi that has a While Loop.

The While Loop be used to constantly update the data.

We may switch to Shared Variables or some other method if we can't  get the While Loop to work.

We want the SignalExpress to update once every second with new data.

Any suggestions for other methods for doing this would be appreciated.

[Evie]

I tried the attached file in SignalExpress and I can't get it to work either.

It has the same problem.  The SE display doesn't update.

[Phil_J1]

Hi John,

I took a look at the VI which you included. Let me point you to the following Guidelines, just in case these aren't the same one that you read:

http://zone.ni.com/devzone/cda/tut/p/id/3203

In particular the section that talks about While Loops at:

http://zone.ni.com/devzone/cda/tut/p/id/3203#toc2

To reiterate the document, the VIs you want to use within SignalExpress need to run to completion in order for SignalExpress to know that new values are ready to be displayed. If you have a While Loop which run indefinitely then no data will be fetched since the VI is still running. Since pressing the Run button in SignalExpress runs the VI over and over, most LabVIEW VIs used in SignalExpress do not need to contain the loop since SignalExpress takes care of the repeated execution. While loops at this point are really only useful for keeping internal state information while Running, but it is recommended in this case, that you hard-wired a True to the exit condition of the While Loop so that it only executes once per SignalExpress iteration.

I hope this helps,

Phil

[dannnnny]

Phil,

The 3203 document was very helpful.  We used the User Step VI Template and our vi is working now.

Thanks,

John