Stream data from a subvi to the main vi - path refnum

hello everyone
sorry my english
http://forums.ni.com/t5/LabVIEW/stream-data-from-a-subvi-to-the-main-vi/m-p/2205150/highlight/true#M...
- refnum boolean worked
- refnum graph worked
- refnum numeric worked
how to create a path refnum? stream data from a subvi to the main vi
where do I start?
thank
Solved!
Go to Solution.

Bom Dia Saille,
Eu acredito que o que você tenha hoje seja isso aqui (Desenho bem simplificado):
Hoje o que você tem é o Aplicativo do Medidor + USB Driver controlando o seu medidor. Basicamente, sua aplciação está dividida em três camadas:
Aplicação - Onde estão as funcionalidades principais do programa (interface com o usuário, apresentação de dados, geração de arquivos, etc.)
VISA - Uma arquitetura de Software para controle de instrumentos. Basicamente, ele se comunica com o Driver USB para poder enviar e receber pacotes de dados através do barramento USB.
Device Driver - Intruções de SW de baixo nível para controlar um periférico através de um barramento.
No desenho, eu aponto duas camadas onde você pode tentar atuar para automatizar suas medições:
Aplicação - Você pode usar o VI Server para controlar o Aplicativo do Medidor (Se este aplicativo tiver sido desenvolvido em LabVIEW, o que eu suponho ser verdade). No entanto é necessário saber se o desenvolvedor do produto permitiu isso (Veja Using VI Server to Pass Data Between a VI and a LabVIEW Executable). Outra alternativa é conversar com o fabricante para ver se ele desenvolveu alguma API (Application Programming Interface) para que você consiga controlar o instrumento diretamente.
VISA - O LabVIEW Fornece uma API chamada NI-VISA para poder enviar e receber informações através de diversos barramentos (Veja Serial Instrument Control Tutorial)
É possível acessar o Driver diretamente também, mas eu não recomendo. O resultado não compensa o esfroço!
Espero ter esclarecido suas dúvidas e espero que você tenha sucesso na sua aplicação!!
Atenciosamente.
Felipe Flores
Engenharia de Aplicações
National Instruments Brasil

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Stream data from a subvi to the main vi

Hi
I’m wondering if someone can help me. I’m trying to stream data from a sub vi to the main vi without opening and closing the sub vi continuously. The data also needs to be extracted from a while loop within the sub vi. background info: The sub vi controls a photomultipler tube, which once it is on it is best kept on. The PMT signal is generated in while loop of the sub vi. Attached are some basic vis showing what I’m trying to do.
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Attachments:
Main page.vi ‏11 KB
test2.vi ‏13 KB

If you are streaming measurements continously I would consider using a circular buffer instead of the queued producer/consumer approach.
Check out this implementataion of such a buffer, use only this if your DAQ device does not have an internal circular buffer.
https://decibel.ni.com/content/docs/DOC-20403
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/Roger

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I want to pass some Boolean/String from a subvi to the main vi while the subvi is still running.
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SubVi.vi ‏11 KB
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Passing data from a subvi to the top level with continuously running loops

Hi All,
This is a very simple question, for some reason the data available at a subvi indicator is not making it to the top level vi. I think it might be something to do with the while loop I am using but I cant figure it out, any help will be appreciated. I don't think I fully understand how the data gets out of a continuously running loop.
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Solved!
Go to Solution.

Hi bennymacca,
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I'm finishing up my little application, and one of the things I cant figure out to get to work is getting live data from a subvi and displaying it on my main vi's front panel.
In my subvi I am sending about 10 commands to the serial port, each time updating a local variable that writes value to a progress indicator. I would like to get that indicator displayed on my main vi so I can see the progress of my subvi.
Currently I have just linked the progress indicator on the sub to a terminal, and connected that to my main vi, but, that only updates when the sub finishes its mission. Is there a way to update the main while the sub is active ?
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Message Edited by Ravens Fan on 08-13-2007 09:34 AM

How do I get values into a vi from a subvi while the subvi is still running within the vi?

Hello
This is my problem. I have a subvi that runs an experiment. At different point in the experiment different instruments are on or off and I have a boolean array display this info. It is updated at various points of the experiment via a local variable. That works fine. Here is the problem though. I run that subvi from a main vi program (that runs it several times for several experiment cycles). I would like to pass the status of that array onto the mainvi to display there too. The problem is that the array in the main vi is not updated until the subvi is done running and thus displays only the array status at end of experiment (instead of changing
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If you have LabVIEW 6i, you can update indicators of a calling VI from
a SubVI, while the subVI is running.
In your case you need
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2) to pass a reference to that indicator to the subvi when you call it
3) to use this reference in the subVI, connect a property node to it and
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-Franz
zkajan schrieb:
> Hello
> This is my problem. I have a subvi that runs an experiment. At
> different point in the experiment different instruments are on or off
> and I have a boolean array display this info. It is updated at
> various points of the experiment via a local variable. That works
> fine. Here is the problem though. I run that subvi from a main vi
> program (that runs it several times for several experiment cycles). I
> would like to pass the status of that array onto the mainvi to display
> there too. The problem is that the array in the main vi is not
> updated until the subvi is done running and thus displays only the
> array status at end of experiment (instead of changing as the status
> changes within the subvi). I tried using a global variable to write
> to it in the subvi every time there is an update, and read from it in
> the mainvi, but that doesn't work, it still displays just the status
> at the end of the subvi execution. Does anyone know how to make this
> work, or if there is a workaround this? Thanks.
Franz Josef Ahlers
Section Semiconductor Devices
Physikalisch-Technische Bundesanstalt
Bundesallee 100
D-38116 Braunschweig
phone: (+49) 531 592 2410
fax: (+49) 531 592 2405

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Solved!
Go to Solution.

muks,
I think you got this post confused with another.
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Here you go. This is simple example. Maybe not the best way, I am just
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When you click on OK button on SliderMain, it opens Slider.vi. Now both
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vishi
"Cy" wrote in message
news:[email protected]..
> I would like to create a pop-up window appear from Labview Interface.
> In this window, I will have a slide control and an image taken from a
> camera. The main VI hav
e to run while pop-up window is open. How can I
> do ?
>
> When I pushed a button, this pop-up window has to appear. There will
> be a slide control and a picture from a camera in this window. Is it
> possible to make appear this windows while main VI Interface continue
> to run ? How can I do this ? Thank you for your answers.
> Cyril.
[Attachment SliderMain.vi, see below]
[Attachment Slider.vi, see below]
Attachments:
SliderMain.vi ‏16 KB
Slider.vi ‏11 KB

Streaming data from cRIO

Hi everybody,
This is quite a general question and I am looking for some pointers\opinions\suggestions.
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How to pass events from subpanel(s) to the main VI ?

hi all,
I found a lot of solutions to pass the events from the main VI to the subpanel(s) but none about passing the events from subpanel(s) to the main VI. In the attached VIs, I just want to generate an event in the main_VI.vi when I click on the button positionned in the subPanel1.vi. How can I do that ?
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Attachments:
main_VI.vi ‏13 KB
subPanel1.vi ‏6 KB

Cedric,
You could use a queue to transfer the button data to your main vi.
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Help the forum when you get help. Click the "Solution?" icon on the reply that answers your
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Attachments:
subPanel1mod.vi ‏10 KB
main_VI mod.vi ‏16 KB
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Stream data from a subvi to the main vi - path refnum

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