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Gan Uesli Starling

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Everything posted by Gan Uesli Starling

  1. Looking to control mass flow from feedback via coriolis meter. Proportional and Integral by themselves would do (no Differential). Looking to build it without the PIDs found only in Real-Time module. Found an ancient example in NI called Simple PID. Here it is... The ancient example in LV 5. But it is so very ancient that LV 2010 refuses to load it. I presume that's what I might have needed. Where can I find something like that, only newer?
  2. My first attempt (successful) at writing a machine control program was in several thousand lines of Perl/Tk. It was talking to a pair of LabJack controllers and ran an automated test rig for cycling contaminated fuel through jet engine nozzles. The GUI part was a major pain. I shouldn't like to do it again, but could if I had to. Getting a little rusty in Perl, mainly because of having LabVIEW. And with Tk having been semi abandoned by Perl, I might be inclined to switch to Python. Not because I find Python superior for a particular reason, but only because I'm getting interested in 3D with
  3. My project is getting rather big, the the function block busy...especially with nearly all wires clearly labled. It'd be a pain to downsize every label, one by one. Be nice if I could reduce the font size of ALL labels in one fell swoop. Any way to do that?
  4. I have a WaveformChart to track an output voltage. I tied a line from a numeric control (used elsewhere) so as to set the Y.Scale.Maximum (write mode) for said WaveformChart (so it would agree with said elsewhere). But changes to the numeric control have no effect on Y scale for the chart. Anybody know why not?
  5. I decided to simply move "DAQmx Flatten Channel String" VI outside the loop, placing it immediately after the Controls IO build array. I no longer have the Error In/Out from that particular VI as easily connectable there, but it'll still do, I think. The VI I'm building is rather big, quite a few signals to recorde. And there are several fo those Controls IO arrays, not just the one. And finally, as the rig is to be a test chamber eventually containing pressurized fire, I'd like to eek out whatever efficiency I might gain no matter how many hoops I myself must jump through to obtain it. Call
  6. Am seeing a red dot (indicating conversion) where I feed an array of I/O controls into "DAQmx Flatten Channel String" VI. Now the I/O controls array is created outside the loop but the VI is doing its conversion inside the loop. For efficiency's sake I'd like that red dot to go away by making the VI's required conversion outside the loop. How best to do that?
  7. I am using 2009, thank you. This one works just fine in the development environment. So I'll stick with it and hold the other ideas in reserve. My thanks to everyone for their input. All replies have brought me a measure of enlightenment. Thank's again.
  8. If I am writing a VI now from which I'll burn an Application later, will the first example work in the VI and not the App while the second example works in the App but not the VI? I'm a bit confused on the distinction. Enlightenment please?
  9. Wanting to get a return of the file path (or string of same) where the running VI is currently in. I can do this in Perl easily. If I wrote a Perl script named "Where_am_I.pl", having only three lines like so... use File::Basename; print dirname(__FILE__) . "\n"; sleep 5; ...and called it via MSDOS from the C: drive, like so... C:\>perl -e U:\foo\bar\Where_am_I.pl U:/foo/bar C:\> ...I'd get the dir where the script resides rather than the current dir from which I called it. I've tried a bunch of ways to do that in LabVIEW, but all I ever get is the CWD, not the script's own dir
  10. Have heretofore only used SCXI and CompactDAC. Am now confronting a brand new PXI system stacked up on my desk without benefit of NI training. Which books and/or on-line tutorials specific to PXI and Real-Time would you kindly recommend that I may upgrade my wetware to synch with these brand new hardware and software?
  11. QUOTE (Neville D @ Aug 25 2008, 03:56 PM) Okay. I got it to work like so... http://lavag.org/old_files/monthly_08_2008/post-10610-1219702442.jpg' target="_blank"> PS -- The JPGs look better now that I edit from BMP to JPG using GIMP with Quality=100% on saving (versus default of 85%).
  12. QUOTE (Ton @ Aug 25 2008, 10:27 AM) Reading a task in Max? I can read any of the individual channels in DAQmx, sure. Individually, those all work. But how might I get these two tasks to run in parallel that way...outside of the VI itself? It is running two tasks which seems to hang. Whichever is 2nd to fire hangs with the error. But I have two 1520 modules in a 12-slot SCXI cage accessed by a 1600 USB module. They feed off-screen to right to a common while-loop but the hang-up is prior till then, at the place shown. It seems to me that there ought to be a way to use two 1520's differentl
  13. QUOTE (Neville D @ Aug 22 2008, 05:46 PM) Sure, no problem. But JPEGs are horribly fuzzy and my thought was that most folks would rather wait the extra ten seconds to get a screenshot that's easy to read. I'll try and remember to append both full-rez and blurries from now on. If I weren't behind the company's firewall I'd upload the high rez to my own Unix box under my desk at home and post links here for those so as to consume storage and bandwidth here only for the JPEGs. Humble apologies.
  14. I get a -50103 resource is reserved error on my SCXI 1500 module, also if I split the tasks across two modules. I am using these via a USB 1600 module slotted into the SCXI card rack. Attached are two screenshots. 1. The circuit. 2. Circuit showing error. How may I get around this error? Please be aware that I am still a novice at LabVIEW when you answer.
  15. QUOTE(Yen @ Jan 29 2008, 01:26 PM) Yup. Found it. And indeed it does work. Thank you. My book, "LabVIEW for Everyone" was not too very helpful with explaining this particular item. And that is why I originally chose to register here. But then while just stumbling around in LabVIEW itself I somehow got to an example...I think by simply double-clicking on the System Exec VI...which was very informative. Once to there I was able to play with various things and get it to work.
  16. Howdy, I am a 52-year old, married, father-of-one, test engineer for Woodward in Zeeland, MI. We make nozzles for turbine combustion systems. I test them. I've been doing that only 2 years. But I have 15 years in automotive fatigue and durability at my former employers of Paustra (3 years) and Benteler (12 years). My familiarity with LabVIEW is beginner-level. I do have one testing machine currently running on LabVIEW 8.0 which I had formerly had running (somewhat kludgedly) in pure Perl. I am entirely self-taught in programming. The history of my experience is as follows: 1. Forth - now
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