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drjdpowell

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drjdpowell last won the day on January 15

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About drjdpowell

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    LabVIEW 2017
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    1999

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  1. Sadly, I still have no experience with PPLs, and you'll have to ask someone else. I have no idea about palettes.
  2. Here's a couple of diagrams. You seem to be doing this: Where the privately-namespaced copy of Messenger Library in your ppl cannot communicate. But I'm suggesting this: Where every component uses a common ppl.
  3. You've just told me the equivalent of: I want two people to talk to each other, but each use a private language that no other person can understand.
  4. I think you should put Messenger Library in a ppl and have all your other code use that ppl. Then everyone is using the same namespace. Why have you not done that?
  5. I think there is a misunderstanding somewhere as what you describe here is almost the opposite of what I suggested here:
  6. Here is a link I found that I think might be the same issue, though with a Global Variable as the communication method between components: https://forums.ni.com/t5/LabVIEW/How-to-access-common-global-variable-between-different-Packed/td-p/3324410?profile.language=en There, as I suggested above, the solution was to put the common dependancy in a common ppl, that all communicating components used.
  7. A short list of possible techniques: 1) Let the hardware do the timing. Things like DAQmx or IMAQdx can provide Events, such as "FrameDone", and some hardware can provide buffered data in precise short periods (every 50ms, say) where you can just make your timeout 0ms, because waiting 50ms means nothing to your UI actions. 2) have a loop/actor send a message periodically. In "Messenger Library" this actor is called "Metronome", and there is an AF component called I-forget-what that does similar. 3) send a time-delayed message to oneself; resending when it is handled. Also on Messenger Library and the AF. 4) Calculate the time till the action is next due, and use that as timeout (or just do the action if the remaining time is zero or negative). Recalculate after an other message/event. Generally, I would advise one never use a fixed timeout value to schedule a periodic action. With the above methods one can easily have multiple periodic actions occurring on different time scales without any interference (assuming all the actions are reasonably quick).
  8. But that wasn't the idea. Your plugins can't pull in different copies of common dependancies; they must use the copy in the exe, be that source or a ppl. You need to consult someone who is an expert in plugins.
  9. A possibly useful link: https://forums.ni.com/t5/LabVIEW/Verify-plugin-source-distribution-after-build/td-p/3771429
  10. BTW, I'm no expert in such plugins, but this statement seems very wrong to me. Your plugins should find common dependencies in the EXE that is loading them, not making new copies.
  11. Ah, so really your issue is about "plug in" architecture where you want to be able to drop new plugins to a folder, and there is the problem of the plugins depending on common code (Messenger Library). I have only previously done dynamically-loaded code that is built as part of the same build as the EXE that loads them, where such issues don't come up. You might be better to ask in another forum, as the issues you have are not Messenger-Library specific and will be common to other such plug-in designs. Another option is to put the entire of Messenger Library in a PPL (changing namespace) but then have ALL your code use this PPL instead of VI.lib (so everything uses the same namespace).
  12. I don't understand this bit. Are your "steps" source code rather than built?
  13. Could you explain a little more what you are doing. I am confused that you are using TCP (something usually used for communication BETWEEN applications) and having namespace conflicts (which happen when you have multiple paths to the same-named thing on the SAME instance). On no condition would I recommend renamespacing the library, as TCP involves flattening the messages to strings, and that uses the class names, which you are changing. The TCP Messengers override the usually LabVIEW flattening for some common messages for reasons of performance, replacing the class names with a much-shorter format using an enum for class type. This is why some messages will still work. But this is strictly limited. I had imagined, when you first brought up Teststand and TCP Messengers, that you were building a separate LabVIEW application, and that Teststand (in a separate application) connects to the first via TCP. That could not have conflicts.
  14. Note: if you have a Tools Network package, you can request assigned ranges of error codes for just your library. For example, "SQLite Library" errors start at 402860
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