Labview created DLL which uses Labview built-in VIs from the ( Digital Filter Design ) "DFD" Toolkit

[wfarid]

Hi Fred,

So, you want me to upload the LabView code for the DLL that you've been testing OR the code for the original DLL that we are targeting (I'm not sure if i'm authorized to upload this one). Please clarify.

Thank you,

-- Walid Farid

Research Assistant, NavINST - Queen's University

[Fred_V]

Hi Walid,

Sorry for the delay - I'd like to take a look at the code for the LabVIEW DLL that you're calling into. Would it be possible to upload that?

Thanks,

[wfarid]

Hi Fred,

 I already uploaded this code, and you can find on page 2 . The file is called MainVI_Source.zip and the name of the main VI is Test_Design.

Thank you,

-- Walid F. Abdelfatah

Research Assistant, NavINST - Queen's University

[Fred_V]

Hi Walid,

I was able to recompile your LabVIEW DLL and retest it in same manner as before, and strangely it appears to work correctly. I've attached your LabVIEW VI Project, and the compiled DLL. Could you take a look at that code, and test it to see if you get the correct results?

Thanks,

[Fred_V]

And the attachments …

[wfarid]

Hi Fred,

I wasn't able to run the project because I don't have LabView 2010, but LabView 2009. So, is it working fine now because you used LabView 2010 instead ? Could you try it on LabView 2009 ? Can you post the steps for building the dll as I might be missing something ?

Thank you,

-- Walid Farid

Research Assistant, NavINST - Queen's University

[Fred_V]

Hi Walid,

I've reattached the files as LabVIEW 2009 files, so take a look and see if you can duplicate my results.

The DLL build process is straightforward; I didn't add any additional dependencies, just added your source file. The same is true for my test LabVIEW application; the primary issue was that I needed to change the Call Library Fuction node to 'Call in Any Thread' or the application would stall on launch. 

Then I copied the entire build folder for the compiled DLL to the application data directory for the test executable. LabVIEW had automatically pulled the primary dependency (the DLL), but I need to grab all other support files including the DFD and ASP DLL's that were added as DLL dependencies.

At this point the application returns non zero values. Two quick things to note about the return values - they differ between LabVIEW 2009 and 2010, and the answer varies in an executable, while it remains constant in the LabVIEW VI.

I hope this helps,

[wfarid · Accepted solution]

Hi Fred,

 1) LabView 2010 created dll : I installed LabView 2010 run-time engine and it was working fine.

 2) LabView 2009 created application/dll : Neither the Application.exe nor the MSVC++ project calling the dll file from the "DLL Build" is working. I attached my desktop captured image with a LabView window showing one of the VIs that the dll was looking for. I'm suspecting that it might be a bug within LabView 2009. Did it work on your side ?

Thank you,

-- Walid F. Abdelfatah

Research Assistant, NavINST - Queen's University

[Fred_V]

Hi Walid,

I think you may be on to something there. I had only saved the files for LabVIEW 2009, without regard for the fairly significant changes in the associated toolkits between 2009 and 2010. When I tested the files more thoroughly I get the same behavior that you describe.

I'll try to isolate the failure case to a narrow set of VIs to file a CAR, but given that the issue appears fixed in 2010, are you able to upgrade and workaround the issue?

[wfarid]

Hi Fred,

 Thank you for your help and follow-ups! I really appreciate it.

 We are still in the process of moving our design to Labview 2010. But I'd say, we located the problem. I'll let you know if we have any more problems with Labview 2010.

Kudos !

-- Walid Farid

Navigation and Instrumentation Research Group ( NavINST ) , Queen's U/RMC - Research Assistant