TS Sequence Context and Invoke Node problems

I have a Vi that was developed in 7.1 and TS 3.1. I inherited this design from a past developer. The Invoke node works fine when loaded with LV 7.1 but not when I load the Vi with LV 8.2.1. I have gone through everything I can think of to correct the problem. Help would be appreciated. [email protected] (contact address to let me know you posted or you can do it directly. Thanks in advance.
Attachments:
TestStand - Dist LabVIEW Test - Sequence Context.ctl ‏6 KB
TestStand - Get Property Value (Number).vi ‏42 KB

I just loaded this vi in 7.1, 8.2 and 8.5 and it works just fine for me. Although my TS version is 4.0. Can you expalin what you mean by it doe not work in 8.2. Does it load correctly? Have you reinstalled teststand into LV 8.2 so that you can open the TS pallette in LV 8.2? Are you running this inside of a sequence and passing the sequence context to it. It will not run correctly if a sequnce context is not passed to it from TS.
Also you should post this in the teststand forum and not the LV forum
Joe.
"NOTHING IS EVER EASY"

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What does mean "property node and invoke node"?

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Attachments:
è¨å®éåèªè¾¼ï¼Excel to string table).vi ‏64 KB

Typically with any activeX programming in labview you drop an reference to an object , open the reference, then invoke the methods and set the properties and when done you close the reference. To select what reference you would like right click on the activeX reference and choose "browse". The excel object library provides many activeX interfaces but typically you would manipulate the application object, Workbook or worksheet but I have only used the excel interface a few times, I prefer to use excel offline and not directly communicate with the application programmaticly. You can also place an axtiveX container on the front panel and select the Excel container object to embed an excel instance on your front panel. Good luck.
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How to get a LabVIEW class object to expose an invoke-node method?

Hi,
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I've looked at (but not completely understood) "Creating LabVIEW Classes". Have also searched for related posts.
The pic below shows an invoke node wired to a class with a Public VI "VAT.Status.Hello.vi". I'd like to see VAT.Status.Hello show-up as a Method. (I just tried "Select Method", and selected "VAT.Status.Hello.vi" but dialog's "OK" button stays greyed-out.)
Cheers.
Message Edited by tbd on 03-29-2007 03:15 PM
"Inside every large program is a small program struggling to get out." (attributed to Tony Hoare)
Attachments:
VATStat.JPG ‏54 KB

Hi Aristos,
      Thanks for the reply!  It was a bit dissappointing, though.
It appears the LabVIEW-class object will be moving away from (what seems to me) a convenient object-interface presented by the invoke-node/method paradigm - which allows us to interface with a large set of "objects" (.NET, ActiveX, LabVIEW GUI, VISA Resource, ?) in a similar manner and independent of the object's origin. Being able to read the methods and parameters that appear in these nodes is also helpful for understanding diagram logic!
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and "in the next version of LV, wiring the LV class to the property/invoke nodes will break the wire so we'll avoid confusion in the future",
... I guess you'll break the wire in the next version, but (perhaps) allow it again - if support of the property node is ever implemented?
Regards.
P.S. For the record, huge THANKS to whoever it was that straightened-out enumerated-types (somewhere) between LV4.1 and LV6.1.  Every time I add or remove an enumeration in a typedef, I silently give thanks to the bright and thoughtful soul(s) who made this valuable tool work so well!
Hello. This is your friendly neighborhood R&D guy for LabVIEW classes.
Regarding your request about property and invoke nodes as relates to LV classes....
Short story: We would like, someday, to support the property node. We have no intention of ever supporting the invoke node.
Long story: As we were creating LV classes, we had to evaluate the right programming interface for these things. We wanted LV classes to behave as new data types in LV. A developer should be able to create a LV class, then give it to someone who doesn't even know OO programming, and that second programmer could use the new data type without learning a lot of new concepts. From this principle, we held fast to the idea that the programming interface should be subVI calls whereever possible. The invoke node is really nothing more than a VI minus the icon. If you want, you can popup on any subvi node and uncheck the option "View as Icon". This will make the node display in a way that has the terminals listed as text, like the invoke node. So, at the end of the day, the invoke node is simply a subroutine call in LV that is language dependent, as opposed to the language independent iconography of LV generally.
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PS -- in the next version of LV, wiring the LV class to the property/invoke nodes will break the wire so we'll avoid confusion in the future of people thinking there's a way to use these nodes.
Message Edited by Aristos Queue on 04-02-2007 09:56 AM
Message Edited by tbd on 04-03-2007 12:39 PM
"Inside every large program is a small program struggling to get out." (attributed to Tony Hoare)

Get Sequence context from ActiveX reference

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I'm not sure I fully understand the question but I'll take a stab at it anyways. First if you want to have seq context of the new execution; review my sample seq file I sent along. In this seq file you can pass seq context of the new execution to a dll in either seq/execution.
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[email protected]
Attachments:
Sequence_File2.seq ‏16 KB
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Solved!
Go to Solution.

A lot of this code should be done different, just for the reason that it is difficult to find such problems. I would suggest you browse examples about state machines to see some 'best practices'.
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[email protected]
"...after all He's not a tame lion..."
Certified Professional Instructor
Certified LabVIEW Architect
LabVIEW Champion
"... after all, He's not a tame lion..."
Be thinking ahead and mark your dance card for NI Week 2015 now: TS 6139 - Object Oriented First Steps

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That is odd
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the 2, the AN asked to right click the Invoke Node(this is step9) and choose initialize. However there is no intialize option on the pop up menu. Anything am I doing wrong? I am using Labview6 and I did add the "enableCustomInterface=True" in the INI-fileT Tall,
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Sapete aiutarmi per favore?
Grazie in anticipo,
Chiara

Grazie Marco. Funziona

TS Sequence Context and Invoke Node problems

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