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Bob Y.

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Everything posted by Bob Y.

  1. I'm guessing that this is a school work project. So, I am not giving you an answer, but I will try to lead you to one. If you want to break a beam and trigger on that, you will need several things: A beam, a beam receptor, and something that will be triggered. For the beam, I have used a laser diode (beam) and photovoltaic cell (receptor) with success before. You will notice a difference on the photovoltaic (solar cell) depending on the presence of the laser diode beam. As for the software, poll for the change and trigger your output (UI?) based on the "correct change". Let us know if you need more help, Bob Young
  2. :!: Yes, but we will have to wait a year until LabVIEW is 21 years old to see LabVIEW 8.21
  3. Have you looked at the Simulate Arbitrary Signal Express VI? The UI in it does some cursor-drag-to-define-waveform stuff. It's built in. If it did a spline instead of just straightline interpolation (or choice of either) that would be cool. Maybe you could steal some of it. Hope that this helps, Bob Young
  4. Maybe you are looking for something like this? Download File:post-1172-1158248591.vi
  5. I haven't done this in LabVIEW, but a quick google search turned up http://en.wikipedia.org/wiki/Round-robin_tournament and http://www.devenezia.com/javascript/articl...oundRobin3.html This seems to be a fairly good explanation and sould be easy to implement in LabVIEW (or with even less translation, a math script node). I might play with implementing it this weekend, but don't wait on me! :beer: Hope that this helps, Bob Young
  6. I have been unable to find the PDA 8.2 link. Could you please post it? I am not really sure it is out yet. Thanks, Bob Young
  7. Express VIs are to LabVIEW what crayons are to art; very few serious artists use them in their work but they get a lot of people to try their hand at art and a few people that try will become one of those serious artists. And those serious artists typically out grow crayons except where it really makes sense in their work. Just another medium for work that most of the beginners will start with and the pros will typically not use. As a pro, I use them but not very often and only when I know it is what I am really after. Elapsed time, DAQ assistant (as a starting point), Instrument assistant (although not often), and the formula one are all I typically use. And now, the File Dialog. Sometimes I just "sketch something out" with them to prove to myself that I am headed the right direction. Some people here seem almost offended by Express VIs but I don't really understand why master artists would be offended by someone handing out crayons. Bob Young
  8. On Monday, 31 July 2006 NI mistakenly released Download File:post-1172-1154382504.mp3 the attached podcast and a few hours later they replaced it with the one advertised on the NI podcast page (by Steve Rogers). Here is the mistaken one. Bob Young
  9. It is so hard to tell because I don't know what to count. If I used LabVIEW on one project 3 years ago, do I count as a user? If I am still using LabVIEW 5.1 today because the company does not see the need to upgrade, do I count? If I haven't purchased just LabVIEW in 5 years because I have an SSP subscription, do I count? It is all so grey! :question: Thanks, Bob Young
  10. The student edition is still under $100. Anyone who is interested in using LabVIEW for general hobbyist use can use the student edition and have most of the capability of the full package. This is what I recommend to anyone who expresses a non-business interest in LabVIEW. The LabVIEW 8.0 Student Edition is due out any day now. You can order it at Amazon or from NI itself. There is also the Lego NXT system do out late summer. All are great ways for someone to be introduced to Graphical Programming. Just a thought. Bob Young
  11. Actually, no. This forum is for more Advanced discussion. The discussion area for first timers and people who just need a little hand-holding (as we all do from time to time) is the Developer Zone on NI's official site. You could post your question Here or Here. If no one else answers first, someone from NI will answer in a day or two. This forum is called LabVIEW Advanced Virtual Architects becasue it is geared more to advanced topics. Design patterns, tricks, discovering and using undocumented features, large project challenges, and multiple developer challenges are the sorts of things that are often discussed here. Hope that this helps, Bob Young
  12. That is true, but this processor can use several different OSes and if it is using one that the PDA module would work with, it would be much easier to program for. It would also be less deterministic and more costly per board. Off hand, I would like to throw out that embedded programming is an entirely different animal from Windows programming and using the PDA module is very much like windows programming. The embedded module is difficult to get used to if you are used to regular LabVIEW for Windows (or Mac or Linux). Programming for a particular processor that does not have a supporting toolkit already developed (only ADI Blackfin has one so far) makes the work of the programmer that much more tedious. I am still not sure of the capabilities of the team involved and that will make all the difference as to what is the best approach. Afterall there are also many difficulties in creating C code programms for embedded systems as well. Hope that this helps, Bob Young
  13. The answer really depends on what OS if any you are running. If you are running Windows CE, you might want to try the LabVIEW PDA Module for PocketPC. I am not sure if Windows Mobile 5.0 or other PocketPC OS is available for this configuration, but if it is, the answer would be LabVIEW with the PDA module. There are some significant differences between Windows Mobile for the PocketPC and the more robust, more deterministic, and typically embedded Windows CE, but LabVIEW PDA module might work out for it as well or at least get you closer. If you are using Embedded Linux, some other OS, or no OS at all, you can certainly use the LabVIEW embedded module or straight C/C++. I can't answer which is better as I don't know your team's strengths with LabVIEW or C. I would like to offer any help that I can as I have done some programming for a Dell Axim X51v (Windows Mobile 5.0 on an Intel
  14. I think that mid January would be good. University is still on break and the cold of the Northern areas could be broken by the welcoming mildness of Austin in January. Just a thought. Bob Young
  15. LabVIEW 5.1 does not have the flat sequence structure. You will need to use the original sequence structure (stacked). In Pane 0 you will have to create a sequence local and wire the time-stamp into it (actually a double in 5.1?). In Pane 1 you will have your loop. In Pane 2 you will have to use the value in the sequence local for the subtraction. I hope that this helps, Bob Young
  16. Here is one way to do it (I think). You dynamically launch a VI; this VI will be your queue generator. You can then launch any VI via the sequence and the queue should be accessable. You will have to keep a reference to the dynamically launched VI in TestStand and be sure to kill it at the end of the sequence. Be sure to let us know if it works . Bob Young
  17. Here is a quote from Wikipedia about what the frequencies should be: Quote: A variety of different tunings is used. The most common by far, known as "standard tuning" (EADGBE), is as follows: * sixth (lowest tone) string: E (a minor thirteenth below middle C
  18. If you do get the toolkit, be sure to look at this Knowledge Base article for instructions of what all you need. Install everything else before you install the toolkit to LabVIEW. There is an update to the sold toolkit that will let you develop directly for Windows Mobile 5.0. The downside is that you also need to PURCHASE Microsoft's Visual Studio in order to use it. NI is not reselling this, so you will need to go to Microsoft's site to get it. You can also develop for Windows Mobile 2003 without purchasing MS's Visual Studio and it all seems to work fine on Windows Mobile 5.0. Hope that some of this helps, Bob Young
  19. I would suggest a picture control. Have a dot in the middle, and let the user drag the dot out of the middle (or drag a separate dot) with the mouse. Reading in the mouse postion is a snap and drawing the dot is also easy. Hope that this helps. Bob Young Download File:post-1172-1147299809.vi
  20. Does this mean that it can't just copy its diagram/front panel into the new VI? It would have to build it from scratch, right? Hmmmmmm. I am sure that would be difficult. I think that scripting could do it, however whenever they get around to licensing it. Thanks, Bob Young
  21. M Ali Amir; What do you mean? Are you saying that you think that this is not a valid copy of LabVIEW? The way I understand it, all copies of LabVIEW are valid. If you don't have a good serial number, the activation will fail and you will be limited to a 30 day demo version. If he is installing from boxed CDs or from a downloaded installer, it should at least install. As for the original problem, I am not sure how to fix this. Just make sure that virus scan has been run fairly recently and is not running while trying to install. Surface scan of the hard drive, clean up the registry, un-install the previous bad one before trying to re-install, etc. I am sure most of this was tried. Bob Young
  22. The Format into String has a bug when you use the digits of precision formatter. If you have a format string with the digits of precision formatter, all significant digits formatting after that will also be digits of precision. See the sample VI. Download File:post-1172-1146087352.vi LabVIEW 8.0.1 This has been reported to NI and the AE duplicated it. SR# 805853 They are going to do some more research. Work around would be to use multiple Format into Strings and concatenate the results.
  23. I have to disagree. If you move from the Express Palette, you will have to basically start over. The Getting Started Manual is written with Express in mind so everything you have been exposed to is Express. This is part of smoothing the learning curve that NI has done a great deal of work on. Louis is already on top of the hill, so to speak, so he does not see the need for the simpler Express VIs and is recommending the more powerful classic subVIs. For someone who is just learning, you need a mixture. From the Express Palette you can get to the more classic VIs as well, so I would not recommend changing the palette just yet. It won't be long before you realize that you use more things from the classic palettes than Express VIs, and when you notice it, that is when I would change (I would guess 2-3 weeks of fairly constant use or 6 months of a small project here or there) That being said, there is an Express VI that does what you are looking for. Execution Control -> Time Delay. The time is in seconds, but it has milisecond resolution and under the hood uses the Wait that Louis is recommending. Hope that helps, Bob Young
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