Viewing and Controlling Executables Remotely in LabView 8.6

[Q7]

I have an application with a main front panel vi that then calls a multitude of sub-vi's depending on what you would like the instrument to do. The main vi is converted to an .exe and distributed with the instrument. The instrument has a small touchscreen but some customers would like to view and/or operate 10+ instruments from one computer.

Here is what I have done:

1. Run the executable on the instrument touchscreen

2. Connect to the server (instrument) on a remote computer(client) using  Operate-->Connect to RemotePanel... <or> through web browser.Connecting to the top-level vi.

3.TopLevel.vi comes up on client OK, but is not running as it is on the server machine.

4. Request Control of Server and Run TopLevel.vi

5. Select for example: Run Test button which brings up the RunTest.vi

6. RunTest.vi now appears in new window on client computer but is VERY LARGE. Resolution on server is necessarily much lower than on client. RunTest.vi cannot be resized due to necessary restrictions on the server's small touchscreen. 

7. Also, I cannot control RunTest.vi as it is not the vi I conected to??

How do I just connect to the .exe and all sub-vis???

How do I display them/resize them on client machine??

I would be happy to only connect to TopLevel.vi and RunTest.vi but why do I need to request control to see the vi's live and updating? Is this an "application instance" issue?

Both VI's MUST BE RE-ENTANT as multiple instruments have to be operated at the same time using multiple instances in the same executable.

[Chris G in AE]

Howdy jbjorlie,

I can tell you that this is not expected behavior for Remote Panels.  As such, I'm curious about how you're implementing them on your instrument.  Additionally, I'm curious what type of instrument you have and what operating system is running on it (Windows XP Embedded, Windows CE, etc).  Normally, you should be able to view the running state of the VI without having to request control of the VI, and I'm curious if the operating system you are using fully supports the LabVIEW web server.  Thanks, I look forward to hearing back.  

[Q7]

Thanks Chris,

The instrument is running on XP embedded and is used to heat an item while stirring is and measuring viscosity. The multiple front panels come from various vi's that perform routines such as calibration, test setup, and actual testing. All of these vi's are called from a heierarchy beginning with the Top Level vi. I would like to be able to control the instrument from the touchpanel on the XPe system as well as from a remote system in an office or some central lab workstation. The software is shipped with the instruments as an executable for use on the XPe touchscreen attached to the instrument. It is up to the end user to network all the instruments together for remote operation. 

[Chris G in AE]

Jbjorlie,

After checking into this a little further, LabVIEW is not officially supported on Windows XP Embedded.  This means that we do not guarantee or test functionality.  We do make a toolkit for deploying programs to the touch panel as of LabVIEW 8.6, but this doesn't seem like what you are looking for.  However, even though it's not supported, it may still work (it looks like it is), but some functionality might not be present.  Is it absolutely necessary that you use a touch panel to control your instrument?  Thanks, I look forward to hearing back from you.

[Q7]

Chris, yes it is imperative that we use the touchscreen. The touchscreen is not the problem. The problem is controlling/viewing the entire executable remotely. How can I control the entire executable by a networked computer? We would like to be able to view and control the current state of the instrument from a remote location. This must be done regularly by your customers...I am just not clear on how to do it. Much like using VNC or remote desktop...only with control over Labview only??

We would also like to be able to "log in" and see the status of a test without control. Not just a single vi but the current front panel running in an executable.

[NathanK]

jbjorlie,

From your original post:

"3.TopLevel.vi comes up on client OK, but is not running as it is on the server machine."

You mentioned that your VIs are marked reentrant which allows them to spawn instances that can be controlled separately by remote panel clients. There is a bug in 8.6 that made it so that when such a VI was marked to run when opened that it wouldn't when viewed as a remote panel and the user has to manually press start. This has been fixed for the next release of LabVIEW.

"6. RunTest.vi now appears in new window on client computer but is VERY LARGE."

What do you mean by very large? Does this mean that the subVI is being displayed at the server's resolution rather than the smaller resolution of the client? Is it a problem with the subVI resolution or just that the window is too large? Does the top level VI have this problem? If you save the subVI on the server with a small front panel is it useable on the client?

"7. Also, I cannot control RunTest.vi as it is not the vi I conected to?"

I played around with this a little bit on XP as I do not have an embedded XP machine available. On XP, with my VIs marked reentrant, and with the subVI set to open the front panel when run, I saw odd behavior where the remote panel client could not view the subVI. I have to admit that this is not a use case that is part of our normal test suite and I had never tried it before. At the moment I don't know why it doesn't work but I am investigating.

Either way, the behavior that you described seems different than what I saw. You said that the remote panel client could not control the subVI- what does that look like? Does LabVIEW give you an error message? It sounds like the subVI was displayed, which I didn't see, but then you couldn't take control of it. Is the subVI set to open its front panel when run or are you calling it some other way?

It sounds like what you are trying to do should work but that your use case has bugs for two possible reasons:

1- Remote panels to reentrant VIs that open subVIs in new windows is not a common use case. It isn't well tested and it would seem to have bugs.

2- I don't know how well remote panel clients work on Embedded XP.

You may find more success, instead of opening the subVI as a new window, loading your subVI in a subpanel on your top level VI. I know this is better tested and works as expected on XP.

Let us know how it goes.

Nathan

[Q7]

Thank you, let me verify something:

Is LabView 8.6 capable of the following:

1. Connect remotely to the Top Level vi in an executable (recursive or not) and then use that remote connection to open and control all sub-vis called by that top level vi?

2. What is the preferred method of remote connection and control for LabView distributed executables. The client and server will not have full Labview, only the engines and executables.

If this is a tested and proven functionality then I can troubleshoot much easier knowing it IS POSSIBLE. 

We can configure our XPe OS to handle any problems that come up from there.

Thank you again, Jeremy