Re-engineering a Labview VI written in 2010 it measures potentiometer nonlinearity.

[Argonath60]

Thank you for your suggestion.

It's not my code so I have been asked to only share it with those who show an interest. If I share it with the forum then that's like hanging out the washing for everyone to pick at. While I don't mind that I have to respect the engineers who worked on this in years past. It's not my code and they might feel bad about me sharing it publicly. Further, I don't know who they are/were so I cannot ask them for their input.

I have a .VI that controls the Stepper and a .VI  that runs measurements from the Calibrator. I have to combine the two through the same USB6212 multifunction I/O.

And I have no experience with sequences right now. 

the stepper VI is basically an example stepper drive .vi  provided by NI, the other is a proprietary package developed specifically for the company back in the day, 2010 ish.

Suggestions?

[BertMcMahan]

I think you have a couple options at this point- you can either hire a consultant to work with you, or do the LabVIEW training stuff and try to get there on your own. It's certainly not an insurmountable task, but doing a sequencer like this one isn't the kind of thing you can just talk through on a forum post.

Trying to go from scratch will be pretty frustrating, I'm afraid, so I'd highly recommend doing the training. At the top of the LabVIEW forum you'll see "NI Learning Center". Start at Core 1 and go until you either hit something you have to pay for or feel like you can continue with your project.

[Argonath60]

Thanks Bert, 

Appreciated, John Essick has been very helpful so far, though his chapter 10 on sequences is somewhat mindblowing for those of us who have never seen this stuff before.

As I said, there is no budget, so I guess I'll keep on truckin.....Thanks.

[Kyle97330]

I know you say you "checked the hardware and didn't find anything wrong with that", but consider this:  LabVIEW code is digital and does not change or decay over the years.  

Your actual hardware, with moving parts, is the most likely to change and decay over time.  

The second most likely is a change in your computing environment.  OS updates, the controlling PC getting slower over time, or updates to any other software or driver on the PC.

The chance of a fault in the LabVIEW software occurring just now and not before is a distant third.  It's not impossible, like if there's a data file that's been getting larger over the years and it just recently got large enough to cause slowdowns, but it's the least likely to be the problem.

[Argonath60]

Thanks for asking Kyle,

The VI didn't change, as far as I can tell, the platform did though. And  the labview release also changed, and the packages (Mathscript RT) also changed, it's not here any more.  No tthat that affects this vi because it doesn't use it, but ther ear ea lot of others that do apparently.

Anyway I digress, the original PC this was running on is smoldering in a corner somewhere in production. It was supplied in 2010.

I have the Vi's because they were backed up on the NAS. The software was not, backed up, and someone decided to buy a new release of 2020 back in 2020 from NI.

I found the registration details in a saved email on the NAS and was able to get NI to help me reinstall/reregister it back in February 2023 or thereabouts. The support contract with NI was for 2020 for 12 months and they told me 'support has expired' so that was as far as  they would go. They did record my details against the records for the 2020 version we purchased and the company details haven't changed.

I got the VI loaded and got  that to work, well sort of, it gives inconsistent results due to the speed a human moves the slider.

The 2010 version of labview was upgraded a few times by all acounts, then it was lost altogether due to PC failure, I don't know what, probably a drive failure, who knows. Then someone bought 2020, then it was ported to that platform, but no one left has ever seen it work properly and the people who did, are not here any more and  there is no SOP to reference.

After more research I found the Stepper Motor Driver VI, which looks suspiciously like the example on the NI Website. Anyway I got that to work, but I have run into needing to combine the two and have not the experience to do that at the moment.  It's not as simple as cut and paste, it needs to go into the correct place in the sequence AFAICT. 

So that is where I am right now. 

The electronics I can handle, but labview is a new experience.  

I decided to try this forum because, well, basically, I'm running out of time to fix the problem. 

Thanks for asking.