DAQmx Scale problem with NI-DAQ v8 and LabVIEW v7.1

[Phillip_Neir]

I am currently using LabVIEW v7.1 and NI-DAQ v7.5. I have an application that creates scales on-the-fly. They are not saved. The user can select one of these scales from a DAQmx Scale Name control and apply it to a channel. The available scales are normally sorted alphabetically. I recently upgraded NI-DAQ to v8 (8.0.0f0). The scales were no longer sorted in the scale name control and the newly created scales were not visible. I uninstalled NI-DAQ and MAX (a somewhat involved process) and reinstalled NI-DAQ v7.5. Everything works again. Is this a version compatibility problem? Will this condition return when I upgrade everything to version 8?

[Otis]

Hi Phillip,

Could you possibly show us a piece of your code that still functions, but demonstrates the behavior that you are talking about?

Thanks,

[Phillip_Neir]

Otis,

I've attached a sample VI that I created to test the problem. As I stated, since I reinstalled NI-DAQ v7.5. everything works as before on my development system. However, I installed an executable version of that VI on another computer that has NI-DAQ v8 and LabVIEW Run-Time v7.1 installed. The condition returned. A third computer with NI-DAQ v7.3 works as expected. A fourth computer with NI-DAQ v7.1 works as expected. I downloaded a 'fresh' copy of v8 and installed it on the fourth computer. Now, it doesn't work.

 The VI creates a scale named 'OnTheFly'. When it works, 'OnTheFly' is available and all of the scales are ordered. When it doesn't work, 'OnTheFly' is not visible and the other scales are unordered. I don't know if this problem is reproducible. I saw it on all three of my machines using v8, but the 'source' of the code is the same. An odd thing happened when I first installed NI-DAQ v8 on my development computer. Many shortcuts lost their association to their icons. For example, MAX, MS Office suite, and other misc shortcuts show up as 'Windows generic'. There is a support ticket (Reference#738571) that mentions this. Even after uninstalling v8, the condition remains. Coincidence? I don't know. None of the other computers with v8 exhibit this problem.

P.S.: rename the CreateScale.exe.vi

[Otis]

Hi Phillip,

Thank you for showing us your code.  I checked it out on my machine (only the latest and greatest version of DAQmx), and noticed the same thing that you mentioned.  I was surprised to hear that the method you were using worked before.  Typically if you want to use a scale in a DAQmx Scale Control then you should save the scale first.

Below is an example of how to work around this issue.


I hope this helps, and it appears to be the best workaround for what you are seeing.

Regards,

Message Edited by Otis [DE] on 02-02-2006 05:07 PM

[Phillip_Neir]

Otis,

Thanks for your efforts. It is not the answer I wanted to hear. I would like to be able to use these 'temporary scales' without the headache of saving and deleting them. Also, I would like to have the names sorted, as before. If you have 50 scales, then hunting through an unsorted list will be a pain. Things worked nicely before. What I would like to know is, how is this process 'supposed' to work? Is it broken or working as designed?

[Otis]

Hi Phillip,

The general functionality with DAQmx 8.0 definitely is how things are supposed to work. 

However, it does seem to save in a peculiar order.  You may want to just store all of your created scales in a string control and then sort things alphabetically and let users choose from a listbox.  The Scale VIs accept strings as valid inputs. 

I'll make a note to inform R&D of this behavior.  If you could fill out the Product Suggestion, then it will help to increase the awareness of the problem.

Regards,