Date exchange between two Vi

[black1]

Hello!

I have two Vi . First and second Vi on PC in boiler room (home control )  . Second Vi i use for second display on tablet android like second monitor for family. For control temperature in my Vi i use numeric control. How to do equivalent control for both Vi? ie when i change numeric in first Vi it change in second Vi and when i change numeric in second Vi it change in first Vi (same priority Vi)?

Thanks a lot for help!

[Bob_Schor]

There are so many questions about what you mean that it may not make sense to make any suggestions until you provide more information.  Some of my questions are the following:

• You have a VI that does something having to do with temperature control, right?  Does it currently work correctly, i.e. can you actually control the temperature by changing a control on this VI's Front Panel?
• Attaching your VI (the actual VI, not a screen capture of the Front Panel or the Block Diagram -- we can't closely inspect, change, and execute "pictures") to your reply would answer many so-far-unasked questions.
• I don't understand what you mean by a second VI.  Does this run on the same PC as the first VI?  You mention an Android Tablet -- what does this VI have to do with an Android Tablet?  Are you trying to establish a Web communication with an Android Tablet using this second VI?
• Have you written this second VI?  If so, attach it (again, the actual VI, not a picture) so we can see it and get a much better idea of what you mean.

Bob Schor

[black1]

Hello!

Thanks for reply!

Ok, lets start:

Vi work correctly ( more one year ) , i can control temperature of room and see some other value.

I attach a front panel capture because Vi It will not work without I/O board, but i attach simple example  of main Vi, part with temperature control.

Second Vi i need for Secon Display. If i undestend correcly - 2 front panels, 1 VI, 2 difference monitors - it is a fantasy! And i will do it to see only fields temperature and alarms, for family It's enough . It run on the same PC in boiler room.  I use "IDisplay" for additional virtual display on tablet with wifi, for house range only.

I have not written yet second Vi, but the basic idea is the definition of a second monitor on the system, the calculation of the coordinates of the display and show the temperature field and alarms. I know how to do it, it's not a problem. The problem is to exchange the setpoint temperature.

Thaks!

[Bob_Schor]

I, myself, have never used it, but it sounds like you might be able to do this with LabVIEW's Data Dashboard (see a Data Dashboard tutorial here).  I'd be interested in knowing if this is what you need ...

Bob Schor

[ijustlovemath]

I'd say a simple TCP socket is the way to go here. Provided the two can be networked of course.

[black1]

Yes, it may be appropriate. But maybe there is a way to do it another way?

[Ionoteka]

I think TCP is probably the easiest way too. I put a link that explains the basics of that here, in case maybe you didn't want to use it because you weren't familiar with it.

http://www.ni.com/white-paper/2710/en/

[Ben]

Help Find Example >>> Search

Search for "Remote Panel Methods".

LabVIEW will expose ActiveX methods over a network. Using VI Server Call by reference nodes it is possible to invoke from one PC and VI that runs on another PC and get the results returned to the original calling VI as if the code executed on the local machine.

In the early days of LV-RT VI Server was THE way to control the RT applcation.

I find this to be a very simple approach because the connection and all of the extra stuff required to pass info via TCP are all handled by LabVIEW.

Ben

[black1]

Hello.

I looked at these two methods, it is very interesting. TCP provides an easy link between the two Vi. But how to organize equal control? So far, not even ideas.

Thansk!

[Ben]

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@black1 wrote:

Hello.

I looked at these two methods, it is very interesting. TCP provides an easy link between the two Vi. But how to organize equal control? So far, not even ideas.

Thansk!

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Make the "Served" VI and Action Engine and implement the logic details INSIDE the AE to coordinate passing control between the nodes. Using a served AE lets you ensure that there are no race conditions between the networked nodes becuase all of the logic should be encapuslated in the AE.

I have used that approach going back to LV 6i (may farther... not sure) and it works as well across a network as it does across application instances and it work fine.

Ben