Datasocket shared variable api

[charris]

Vaibhav:

Apologies for the delay in reply.

There is a tool built into LabVIEW for monitoring the shared variable engine and its deployed variables on the system. It's called the Distributed System Manager, and you can access it from within LabVIEW by going to "Tools --> Distributed System Manager." You can also access it from the Start Menu in "National Instruments --> NI Distributed System Manager."

The shared variable API is located on the functions palette of the block diagram in "Data Communication --> Shared Variable" where you were looking. There should be more than two functions; here's a screen shot of the palette in LabVIEW 2010 32-bit.

[Vaibhav]

Hi Caleb,

No problem. I was also diverted to another job for a week. 

Thanks a lot for your guide to the Distributed System Manager. Unfortunately none of the documents I read could point me to this tool. Me too, never "saw" it before. 😉

I have now opened it, and trying to see activities of the shared variable I am using, but the values do not change, even though the operations occur. 
I am using the "psp" URLs to access the shared variables, and read/write their values using Datasocket functions. What could be the reason?

As for the different functions on Shared Variable palette, no, I don't see the functions you are showing. I am still using LV 8.6. Have already got 2010 Fall version of LabVIEW, but don't want to upgrade until I finish the current job. I see other functions however, after installing the DSC toolkit. But not the ones you are showing.

[Vaibhav]

The two palettes I have for shared variables are - 

and

.

So, is this a version difference?

The reason I haven't upgraded to 2010 version is that I am afraid the new version will make my old version VI's unstable, or that I might spend more time in upgradation than actual development. The articles I read about multiple versions, do not clearly say if I can have two or more versions installed with my choice of selection while building application installers. I have two versions, 8.2 and 8.6 on a computer, but as I remember, while building installers for my application, the supporting files are taken from the newer version by default. Right?

May I install 2010 and keep 8.6 without problems in creating installers? And how about one program working on 8.6 and communicating with another program developed on 2010 and running on a 2010 environment?

[jgcode]

---

@Vaibhav wrote:

As for the different functions on Shared Variable palette, no, I don't see the functions you are showing. I am still using LV 8.6. 

---

The Shared Variable API was released in LabVIEW 2009, so unfortunately you won't see it in LabVIEW 8.6.

[Vaibhav]

Thanks Jon. 

Now looking forward to responses for my other two questions above. 

[jgcode]

---

@Vaibhav wrote:

Now looking forward to responses for my other two questions above. 

---

Vaibhav

You can install multiple version of LabVIEW side by side (I currently have 8.2, 8.5, 8.6, 2009 and 2010) with no dramas.

The only thing you may have a conflict with is device drivers.

You can only have one version of these installed at a time.

So if you install 2010 then you will most likely end up installing the current drivers so you can get access to the APIs in the 2010 Dev environment (obviously an older pre-2010 driver will no have known about 2010)

.

If this conflicts with any current application development / client setup then I have done the following to get around it:

- Use Virtual Machines with specific versions of installers installed, so I have a custom image where do that client's development

- As part of your client deliverables include the driver installer(s) separately to you application installer (i.e. all drivers are available as a .zip downloadable from ni.com) 

Cheers

-JG

[charris]

Vaibhav:

Sorry, I'd forgotten that you were using 8.6. JGCode is correct about the API being introduced in 2009. 8.6 had the node and flush functions, but none of the programmatic interaction capabilities.

I can also confirm his note about compatibility. You can have multiple versions of LabVIEW installed on one PC, and the application builder will remain separate for each version. The version of the application builder used is entirely determined by what version of LabVIEW you build from. It's a component of each individual LabVIEW installation.

The recommended order for installing is LabVIEW (oldest to newest), toolkits/modules, then device drivers.

[Vaibhav]

Thanks Jon and Caleb. 

So this means I can build my application installers in whatever version I prefer (initiating that version of LabVIEW). This resolves one issue. And regarding the device drivers - I don't use NI device drivers, unless NI-IMAQ for USB is considered a device driver too. Is it?

[charris]

Vaibhav:

I'm not that familiar with our Vision SW, but I would consider it to be one. Either way, if you want funcitonality in the newer version of the software, I'd reinstall it after installing LabVIEW.

[Vaibhav]

Ok, will try to explain as I got it. 

My concern is if the newer version has a newer IMAQ version. Which means my old one will have to be upgraded. In this case, I will lose independence of the LV8.6 version, because the IMAQ version for the LV8.6 won't be available anymore (as being suppressed by the newer version of IMAQ) and this newer version of the IMAQ won't be usable in LV8.6. Meaning, LV8.6 on my computer will not have the IMAQ functioning in it. 

Right? Or am I not getting it?