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Jordan Kuehn

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Everything posted by Jordan Kuehn

  1. Couldn't you kill the process via the command line? This VI from the dark side shows some of the commands. https://decibel.ni.com/content/docs/DOC-9277
  2. I second crelf's questions and suggestions. Without knowing what kind of power source you are trying to switch, what load you are driving, and how fast you want to switch it, you can achieve this with a suitable relay and a single digital output line. If you have an ni motor controller for the stepper motor you mentioned you can likely find and example for it in the example finder in LabVIEW (Help->Find Examples...)
  3. I just got an email from NI that I passed the CLD exam! I've been poking around here for some time, but not really posting much though I'm sure that will change. There's not too many people in the world that know what a CLD is, so I figured I'd come share it here.
  4. I haven't experienced any of these issues you describe. Running LV2010 on both my desktop and laptop. Perhaps something is wrong with your machine. As far as modern looking controls, I find myself using the system controls a lot. They look nice in windows 7 and decent in XP. There's also a few controls suites in the package manager that are nice.
  5. Here's hopefully a simple question: What is the best method for communicating with an RT target with a Host controller (windows) that may reconnect at any time? Network variables, Remote Panel, Web Services, tcp, udp? I've used network variables and networks streams plenty, but network variables just don't seem reliable enough and network streams hang when connection is lost. Remote Panel and Web Services seem attractive due to the fact that everything is hosted on the target. I don't need deterministic control on the host interface, just a decent UI. Thoughts?
  6. As suggested earlier, post your code and we can be more helpful. Perhaps even a VI Snippet. tushar gave you good advice regarding timing when the trigger occurs. To further elaborate, if you are simply wanting the time from execution to the first threshold, you can place a tick count vi before your while loop. Place another inside the while loop inside a case structure that has the selector wired to the same boolean as what turns the LED on. In the false case you can put the put the tick count from the beginning. Then subtract the two and conditionally wire the result into a numeric indicator. When true you'll see the time between start and threshold, when false you should see 0. I have a feeling you may need a little bit more sophisticated approach, but this should get you started for now.
  7. This is probably what you are looking for. Once you have an ODBC reference you can call the database by name. Here's some stuff from NI: http://digital.ni.com/public.nsf/allkb/47A8CF66D5E3C8CC8625720A006139D6
  8. Here are my get/set temperature vi's for a Watlow F4 controller. You also need the NI Modbus library. And there seems to be an issue with the VI snippet. The clusters constants there can be remade and should have RTU and 1 as the values in them. Hopefully this is of some help to you.
  9. I believe you can comment on the review to clarify some of the focus of the book. Here is a generic article that might be a little useful.
  10. Shouldn't the software work under evaluation mode at least? Also, there is offline activation that is possible.
  11. post an actual image as well, and you may get some tips that relate directly to your application
  12. Thanks for your quick replies! Justin, that hit the nail on the head and did a great job of getting rid of my confusion. I think right now I can get away with refactoring to poll the event structure occasionally, but will keep everything you said in mind as I move on to other projects.
  13. I've recently picked up the JKI state machine and am really enjoying it. However, I have a (hopefully not stupid) question regarding the UI aspect of it. From what I see, the event structure only ever executes while the state queue is empty. In this event structure you put controls that you want to use to trigger new actions and other controls you put in a case to read as necessary? How then do you ensure responsiveness from one of the event controls if the state machine is off running for awhile through the queue? For example to have the program respond to a click of the built in 'OK' button and stop execution immediately rather than waiting an indeterminate amount of time while emptying the queue? Perhaps my thoughts aren't too well organized, but any pointers to discussions or just some advice would be great. I think what I'm after may be an asynchronous design and to move the event structure to a parallel loop? A simple example would probably speak a 1000 words here.
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