Abitrary Waveform with LVM File

[jsm2ne]

Before, importing an abitrary waveform file to the VirtualBench environment was accomplished through an option in the drop-down toolbar, and the import wizard allowed the import of LVM files. Since a more recent firmware update, this is now accomplished in the panel containing the function generator options, but the import wizard constrains files to .txt and .csv only. Has anyone figured out how to load an arbitrary waveform as an LVM file in the most recent firmware update?

[Reyquaza]

Hi jsm,

I'm not sure why this option is unavailable in the new update. What workarounds have you tried so far? Are you able to open your LVM file in a text editor, save it as a different file format, then import it?

[Shruti_Shirhatti]

Hello there,

Need a few clarifications from you to help us better understand what you're running into.

1. Would you please attach a screenshot of 'option in the drop- down toolbar' that you're referring to?
2. By 'VirtualBench environment' in your post do you mean the LabVIEW API?

It is not possible to load .lvm files in the VirtualBench SFP. You will need to use LabVIEW to create the .csv or .txt file from the .lvm file. You can use the “Convert from Dynamic Data” VI set to an array of doubles and write that to a .txt file (one value per line).

You can still use the LabVIEW API to configure the arbitrary waveform using the .lvm file

There should be no change in behavior after upgrading to the latest firmware.

Let us know if you have more questions. Once we have more inputs from you we can definitely help clarify what you're seeing.

Thanks,
Shruti

[jsm2ne]

Rey A,

We can convert the .lvm into a .csv file; however, the column headers in the .csv file then have to be formatted so that the VirtualBench recognizes the data appropriately. Not a big deal for a single user. However, the idea is that in a classroom where many students are using LabVIEW to generate a waveform, then inputting that waveform into the VirtualBench to compare against real-time input, they will simply import the .lvm file, as opposed to exporting as a .csv and then formatting the headers. 

Thanks,

Jesse

[jsm2ne]

Shruti,

1. The drop-down tool bar feature was in a prior firmware release; meaning, the option is no longer there. I am unaware of how to downgrade a VirtualBench to a previous firmware release. Is that possible? If so, then I can screen cap the toolbar option that allowed the direct import of .lvm files.

2. The VirtualBench application is run as an environment where a user interacts with a GUI that displays the data running through the VirtualBench. This GUI is the environment I refer to.

As for the rest of your reply, please see the correspondence with the NI Applications Engineer.

Many thanks,

Jesse

[JoeFriedchicken]

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@Jessie wrote:

1. The drop-down tool bar feature was in a prior firmware release; meaning, the option is no longer there.

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I'm confused by this because the arbitrary function generator was added in version 15.2 (announcement) and the video shows the new arb button. Previously, there were these releases (with more details here) that did not have an arb button:

1. 1.1
2. 1.2

Are you thinking of another application? Or would you add more details about what you remember? Perhaps we're talking about the same thing in a different way.

[jsm2ne]

I believe we are speaking about the same thing in a different way. The arbitrary waveform function is newer, I see where I was confusing terminology. Prior to this arbitrary waveform function, it was possible to load an .lvm file for a waveform onto one of the channels (1 or 2), and view it in the VirtualBench GUI. It was done for various final projects in the undergraduate EE department here at the university. 

Thank you for the clarification. Sorry for the confusion.

Jesse

[JoeFriedchicken · Accepted solution]

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Jesse wrote:

Prior to this arbitrary waveform function, it was possible to load an .lvm file for a waveform onto one of the channels (1 or 2), and view it in the VirtualBench GUI.

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Are you saying you could load a waveform into the MSO or another instrument in the VirtualBench GUI?

The only similar feature that VirtualBench has is a reference waveform for the scope, which was also added in 15.2. The announcement post that I linked above has a video demonstrating that feature as well.

Do you have any screenshots from the previous undergraduate design projects? I still think we're mis-understanding each other.

[jsm2ne]

I've been miscommunicating because I was missing a piece to the puzzle... I tracked down the right source at the university and discovered that there was a LabVIEW program written in-house that allowed you to directly upload .lvm files into the VirtualBench, as well as preview the input data before inputting it. This executable allowed for waveforms generated in Multisim and LabVIEW to be uploaded. There was no direct import through the VirtualBench software. Many thanks for your correspondence ultimately leading me to the solution. Apologies for any confusion!

[vaguy]

Hello All

I was the one that wrote the LabVIEW program that read in an LVM file and uploaded it to the VirtualBench. It worked quite nicely and gave a small preview of the data on a graph indicator on the front panel. That being said, I think that it was a significant oversight for the integrated arbitrary waveform software not to accept the LVM file type. After all, it is a standard NI file format for signals! We frequently use LVM files generated in Multisim as a signal source for the VB, and I expect that we will just stick with our add-on. It would be extremely useful if the VB could export a LVM file of the on-screen data as well.

Next release????