Re: How to talk my company into allowing OpenG usage?
Derrick; Well, since I am not sure who is your customer, the following answer may apply completely, partially or not at all. My assumption to think that the answer may apply to you is because of the phrase "defense contractor". On a higher level, the problem you are facing is called Assurance: ground of confidence that a product perform as advertised. Within the United States, the policy is that products acquired by US Government Departments and Agencies must be subject to a standardized evaluation process (National Information Assurance Acquisition Policy, NSTISSP No. 11) The US government position is that there is room for both proprietary and open source software, and it is not going to say that open source is better than proprietary or vice versa. The important issue is obtaining assurance that the product performs securely and to obtain that assurance it rely on a standard evaluation/certification process. The simple (US only, at least) answer to your question is that you are free to use open source software in your project. So, when approaching your management the argument should be that the value of open source software must be and will be demonstrated via evaluation. In other words: - To blatantly state that open source software is crap, is crap. It must demonstrated. - The fact that you paid for a software, it has certain license, or was written in house is not enough. Now, this also applies to open source software: - The fact that open source software can be examined by a large technical community do not satisfy the criteria either. Again, its value must be demonstrated. Of course, the answer may become more complex depending on the extend of your project. Regards; Enrique Vargas www.visecurity.com
Re: how do I de-multiplex and sample signals that shares 1 input analog channel?
So the sensor isn't for the detection of the LED itself but the light that passes through some sample? If that's the case, then LabVIEW and a DAQ board should be able to do the job. I'm not at a computer with LabVIEW right now so I can't post an example but you would have a while loop that would cycle through the three different control signals. In the loop would be a single measurement. The result of the measurement would be placed in one of three different arrays. Cycle one results would be placed in array 1, cycle 2 in array 2, cycle three in array 3, cycle 4 in array 1, etc. A little modulo arithmetic on the loop count and a case statement with three different numeric cases should be all that you need. If you need an example, I'll see if I can post something when I'm back at work on Monday.
Re: Why is the front panel "inactive" when using event structures
Sounds like you might have a infinite loop or vi waiting for data. If you post your code, we'll have a better shot at offering solutions. Tim
How to add CR and LF on a command in Labview?
Hi, I am using the Walker MG-10D Gassmeter, and this instrument requires that all commands must be terminated with CR and LF. How can I do that? Could you please give me an sample example for " *IDN? " command? I am using Labview 6.0. Thanks a lot.
Re: Visual source safe
Best of all, CVS and TortoiseCVS are "free" -- same goes for Subversion and TortoiseSVN. ;-) -Jim Craig Graham wrote: If you're only just moving to source code control, I recommend NOT using VSS. Google for "Visual Source Unsafe" and I think you get lots of reasons why. I use CVS, and although there's no native support it's still very simple when using one of the "helper" utilities surch as Tortoise. I gather Subversion is supposed to be better than CVS, but I've no pressing reason to go looking for a replacement. -- Dr. Craig Graham, Software Engineer Advanced Analysis and Integration Limited, UK. http://www.aail.co.uk/ - Original Message - From: "James Stewart" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Friday, April 23, 2004 3:10 PM Subject: Visual source safe Does anyone have experience using Visual Source Safe with LabView code? Are there any issues to consider? Is there a recommended way to implement it with LabView? Thanks, James/.
Re: Visual source safe
If you're only just moving to source code control, I recommend NOT using VSS. Google for "Visual Source Unsafe" and I think you get lots of reasons why. I use CVS, and although there's no native support it's still very simple when using one of the "helper" utilities surch as Tortoise. I gather Subversion is supposed to be better than CVS, but I've no pressing reason to go looking for a replacement. -- Dr. Craig Graham, Software Engineer Advanced Analysis and Integration Limited, UK. http://www.aail.co.uk/ - Original Message - From: "James Stewart" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Friday, April 23, 2004 3:10 PM Subject: Visual source safe > Does anyone have experience using Visual Source Safe with LabView code? > Are there any issues to consider? > Is there a recommended way to implement it with LabView? > > Thanks, > James/. > > >
RE: (DOS-Like-) key control : Ideas wanted
Uwe, Would the new keyboard vis in LV 7 do what you want? They will return the keys pressed by the operator without needing to be in a control. I would probably use a simple loop to monitor the keyboard and send commands into a queue whenever specific keys are pressed. You could enable/disable the keyboard monitoring using a more complicated key combination (CTRL-K or something). This way, text could be entered into controls without activating the commands. Bruce -- Bruce Ammons Ammons Engineering www.ammonsengineering.com (810) 687-4288 Phone (810) 687-6202 Fax -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Uwe Frenz Sent: Friday, April 23, 2004 3:45 AM To: list LV-Info Subject: W: (DOS-Like-) key control : Ideas wanted Hi all, I had at least two customers that wanted to have a keyboard control for a rather complex LV app (ECG analysis tools). Such like old 'Wordstar' or Word3 had. For the younger ones: pressing dedicated keys on the keyboard activates special functions under specified circumstances. For example, the key used to be 'one (line) up', 'one left', 'to the left border' and so on. JUST that key did that, meaning there was no or mouse click or anything else needed neither inbetween two of such key strokes nor after the last one. I had tried several attempts starting with LV 5.1 and none of them really satisfied me nor the customers. Don't want to bias you with those attempts... Has anyone of you some ideas or even better some proven concepts or code to share? Any ideas are welcome! BTW, There are better UI concepts for most UIs, but if there are literally 10th of different actions availabel that must be performed quickly and sometimes many of them, then such kind of an UI is still usefull. Takes as few actions as possibel and can be quite quick. In this special case a 96 channel ECG was transformed to a voltage mapping onto a cube around the heart. This cube is displayed from two opposide views, where the view angles must be changed. The voltage levels of different curves must be changed, curves added/deleted, some algorithms for the mapping or potential adaption are to change and so on. Greetings from Germany! -- Uwe Frenz ~ Dr. Uwe Frenz Entwicklung getemed Medizin- und Informationtechnik AG Oderstr. 59 D-14513 Teltow Tel. +49 3328 39 42 0 Fax +49 3328 39 42 99 [EMAIL PROTECTED] WWW.Getemed.de
Re: return to the previous step
You you are right because it gets complexer, but what do you mean with state machine. could you send it to me so that i can study it. Thank you very much
Re: VI loads slowly if VISA serial control is on the front panel
What version of LabVIEW and VISA are you using?
Re: write jpeg.vi path issue
Well I ended up applescripting the files from my labview computer to the server as you don't seem to be able to put a path in labview with commas and get things written to the unix server. I browsed for the unix folder using safari. it gave me this. file:///private/var/automount/Network/Servers/acts erver1.cbl.umces.edu/local/apache/htdocs/Alliance /MidAtlantic/buoyimages/salin2.jpg I went and put this in the path control in the jpeg vi and alas it didn't work. So I changed everything to commas and this didn't work either. Perhaps it is a mounting problem. I need to send from the labview to here. Thanks for your suggestions though.
Re: How can I eliminate spaces from a file?
I'm glad it worked.. I keep forgetting to transfer my examples to LV6.1.. :o)
Re: Driver Templates
Thank you for being more specific. I agree with you that these could be more consistent, mostly by removing colors or by making the coloring more consistent. I suspect they got this way by harvesting them from completed VIs. Personally I think they are a good start, and with a few rounds of iteration based on good feedback, I think this will wind up being a nice resource compared to anything I've seen out there. Now if I could just find the time or an interested party to build an icon editor that supports editing with measurement and instrumentation clip art. Greg McKaskle
Scripting toolkit available for download
A new release of the LuaVIEW scripting toolkit is available for download. Get it here: http://www.citengineering.com/LuaVIEW/download.html To learn about the new features, review the changelog: http://www.citengineering.com/LuaVIEW/changelog.html The toolkit is free for non-commercial use, personal use, and technical evaluation. Albert-Jan
Re: return to the previous step
Thank you very much for your help with the dialog boxes. I have another question, i want to do the same thing but this time with vi's. I want to return from one VI to another. The problem is, that when i choose to go from one to another, i can't return. How can i solve this problem? I am using labview 6.0
Re: Using Numeric Integration.vi: Is this correct?
The "problem" that the function is not defined at negative times tau is a common one: it also happens e.g. in cross- and auto-correlation formulae. A real-world sampled signal always is measured during a finite period of time (mostly starting by convention at t=0), but mathematically the formulae assume an integration from -infinity to +infinity. You may look at the real signal as a product of an ideal one (unlimited in time) and a rectangular window function with value 1 between time=0 and time=T and 0 elsewhere. A Fourier transform of a (bounded in time) function can therefore be considered as the convolution of the Fourier transform of the (unbounded in time) function with the Fourier transform of a rectangular function (which is an x/sin(x) funtion, AFAI recall). In order to minimize the related artefacts in FFT, people often use other than rectangular window functions before FFT'ing, the 'Hanning' and the 'Hamming' type functions being most widely used. I don't know if for the formula you are evaluating also such a windowing 'trick' is possible to reduce the artifacts of the function being defined only between 0 and T, but to start with, I would simply assume that fcc(tau) is 0 for tau<0 and for tau>T. (PS: another argument why in your formula a functional relation and not a product is meant: if it were a product, the integrand could be converted like [fcc*(taumax+tau)-fcc*(taumax-tau)]^2=fcc^2*[2*tau]^2=4*fcc^2*tau^2, i.e. taumax wouldn't appear any more...) regards Franz
Re: Anyone know how to generate PINK noise in a Labview VI?
To quote someone else: "White noise is a sound that contains every frequency within the range of human hearing (generally from 20 hertz to 20 kHz) in equal amounts. Most people perceive this sound as having more high-frequency content than low, but this is not the case. This perception occurs because each successive octave has twice as many frequencies as the one preceding it. For example, from 100 Hz to 200 Hz, there are one hundred discrete frequencies. In the next octave (from 200 Hz to 400 Hz), there are two hundred frequencies." "Pink noise is a variant of white noise. Pink noise is white noise that has been filtered to reduce the volume at each octave. This is done to compensate for the increase in the number of frequencies per octave. Each octave is reduced by 6 decibels, resulting in a noise sound wave that has equal energy at every octave." Therefore my understanding of how you would create pink noise is to 2nd order low pass filter white noise, with the 6dB point (cutoff frequency) at 200Hz. The second order filter will give you the 6dB/ocatave dropoff as frequency increases. If you have LabVIEW 7 you may do this with two express VI's. Here's what I did: - Express VI: Simulate Signal - Signal type: DC - Offset: 0 - Check the option for Add Noise: White Noise / Gaussian White Noise - Set Samples per second (Hz) to: 44100 (This gives us good CD quality white noise :) - Express VI: Filter - Type: Lowpass - Cutoff Frequency (Hz): 200 - IIR/FIR: IIR - Topology: Butterworth - Order: 2 When these are finished, wire the Simulate Signal--DC with Gaussian Noise Output to the Filter--Signal input. The output of the filter will be pink noise. For comparison use two of the Spectral Measurement Express VI, one for the input signals to the filter (white noise) and one for the output signals (pink noise). Configure these to show power spectrum or power spectral density and create graph indicators for their outputs. Map the x-axis of these graphs to logarithmic, auto-scaling off (with the same scale values for both), and you will see that the filter input signal has a fairly constant spectral density, while the output signal has a fairly linear decay as frequency increases.
Slow serial communications using VISA Read
I am not impressed with the speed of the VISA Read vi in LabView 7. Reading only 45 bytes in a tight loop I can only read at about 20 loops/sec, even though when I 'scope' the input line the data is finished being aquired long before the loop begins again. Even at 115.2 Kbaud. I have tried selecting the 'Do I/O sychronously' but it does not help. Why is it so slow (I am trying to run at 40 loops/sec which is only 45 bytes X 40 = 1800 bytes/sec)? I am thinking about buying a 3rd party COMM driver *.DLL and using the Call Library Function Node to get faster response. Has anyone done that? I am considering the COMM-DRV/Lib software from WCSC(Willies Computer Software Company). Has anyone used it? They say many people have used their software with Labview. Thanks.
Re: starting a terminal
I looked at that example in the sample folder. Thanks. Do you know of any other examples that do not reside in the ni folder? Possibly online
Re: How accurate is the wait function when using really long waits?
Hi, For this type of resolution (30 seconds), I see absolutely no problem with getting the desired results. Although the operating system may decide not to give LabVIEW the CPU immediately, it almost certainly would be within 30 seconds if there are plenty of system resources and not many programs running. Allen P. Applications Engineer National Instruments
Re: Need Help: How to design USB Driver for USBN9603
Well, I don't see how you could get at the information necessary to talk with this device from the link you provide. Doesn't National Semiconductors have a Software Reference driver with SDK you can purchase for this device? You definitely need Software driver specific informations, such as the manufacturer and product ID, but also some more informations about the endpoints and possible stream formats. Yes it seems rather difficult to me. Not a single weekend project for sure. Rolf Kalbermatter
Re: 3D multiplot mesh
Hey Orko, First to address changing the color please refer to the following link. http://sine.ni.com/apps/we/niepd_web_display.display_epd4?p_guid=B123AE0CBA16111EE034080020E74861&p_node=DZ52000&p_source=External>Plotting Arrays of XYZ Data Using the 3D Surface Graph This example demonstrates how to change the color of the plot. One thing to be aware of is that this example modifies the color of plot 1. To plot more than one signal please refer to a second example. http://sine.ni.com/apps/we/niepd_web_display.display_epd4?p_guid=B123AE0CBA19111EE034080020E74861&p_node=DZ52038> Plotting Multiple 3D Plots on a Single 3D Graph (Windows) This example uses the 3D Surface VI which calls the Plot3DSurface method not the Plot3DMesh method but the code for Plot3DMesh would be very similar. There are two main things that are done in this example that you need to include in yours. First the example uses the Set Plots VI to add a certain number of plots to the graph. Second when making the call to Plot3DSurface (inside the 3D Surface VI) the method is passed a reference to a specific plot not a reference to the graph. You'll need to pass each Plot3DMesh method a reference to a different plot. Making these two changes to your program should allow you to have multiple plots with different colors. I hope this helps! Sarah Miracle National Instruments
Re: starting a terminal
Hi, CVI has a very complete library for serial communication. Programming your own terminal would not be very hard, actually CVI ships with an example that can give you a good idea on where to start. You should be able to find the example at C:\Program Files\National Instruments\CVI70\samples\rs232\serial.cws This example icludes a nice UI that allows you to configure the serial port. Let me know if you have any specific questinos on this. Regards, Juan Carlos N.I.
Re: How can I eliminate spaces from a file?
Couldn't you just use "Read from spreadsheet file" and wire a "space" character as delimiter? If this does not work right, you might have variable numbers of consecutive spaces. Please post a sample data file so we can see what's best).
Re: which is better for labview - 2000 or XP?
Windows 2000 should do the job well. I cannot comment on Windows-XP.
Re: Limit to the sampling rate for an HP4192 Impedance Analyzer?
Unfortunately it says I can't open your vi, since I'm only using Labview 6. Is it possible for you to take a screen shot of the vi, and send it as a JPEG or other image file? Thanks.
Re: Filter Express vi building appllication problem.
Neuvos, Thanks for this feedback. Yes, we are already aware that the problem is with the frequency limits, but only when the VI is used as an express VI. Converting it to a regular VI, even with those limits, resolves the problem. Zvezdana S.
Re: 3D multiplot mesh
Hey Orkun, Although the example I attached doesn't use the plot3D mesh invoke node it does successfully plot two signals on one graph. I would suggest using this example as reference for modifying your program to plot more than one signal. The same techniques that allow more than one plot in this example will apply to your program. As I pointed out before there are two main things you'll need to modify. You'll need to create multiple plots and then make sure you're referencing different plots when using the invoke node to call Plot3DMesh. I hope this helps! Sarah Miracle National Instruments
Re: 7-segments like digital indicator
Eh... thanks! I learn http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101&RPAGEID=135&HOID=50650008009257&UCATEGORY_0=_49_%24_6_&UCATEGORY_S=0&USEARCHCONTEXT_QUESTION_0=ni7seg.ttf&USEARCHCONTEXT_QUESTION_S=0";>that trick from the fellow wireworker Mr. Jean-Pierre Drolet, who always amaze everybody with his knowledge on LabVIEW. So, I guess he is ultimately the person to thanks! Enrique
Re: Tab Control will not build properly if "tab location" are on left or right.
Hi Wil, I opened your Tab Control VI in LabVIEW 6.1 and LabVIEW 7.0. In LabVIEW 6.1, the tab control did show up in the weird way you described. However, in LabVIEW 7.0, the tab control looked normal. It could possibly be an unexpected behavior in LabVIEW 6.1 that was fixed in LabVIEW 7.0. Download the evaluation version of LabVIEW 7.0 and give it a shot. http://ni.com/labview Sincerely, Feroz National Instruments
Re: EXE building, where can I found "get info.vi" ?
Hi HeVi, Please take a look at the following document that discusses your error: http://digital.ni.com/public.nsf/websearch/FEE9D75A70FB8EBA86256A9D00498B8A?OpenDocument";>When Running My Executable Made in Application Builder it Gives ERROR 7 Search for the Get Info file on your computer. Add it as a dynamic VI as the document above indicates when you build your application. Sincerely, Feroz National Instruments
Re: Slow serial communications using VISA Read
Chris, as I said in last post I have a DELL 2.8 GHz, Pent.IV (XPS system) with 512 MB RAM. I have used the vi with both the standard RS-232 (COM2, up to 115.2 Kbaud) port and also the Sealevel USB to RS422 (COM5, up to 230.4 Kbaud)converter. With each COM, I was not able to get more than ~20 cycles/sec with the vi I sent. Thanks for the help. Rob
Re: starting a terminal
Sure, just go to http://www.ni.com/examples you can serach ther for serial and limit your results to CVI. You should get about 12 hits with different implementations of serial communication. Good luck! Juan Carlos.
Re: how do I de-multiplex and sample signals that shares 1 input analog channel?
I do need to know exactly which one is on. Briefly, my project is a sensor that will detect blood oxygen saturation level. The sensor needs to detect the concentrations of hemoglobin(potential oxygen carrier) and oxyhemoglobin(oxygen carrier)in the blood. They have different light absorption patterns due to different wavelengths. That's why there are 2 LEDs, Red and Infrar Red (2 equations 2 unknonws)and it is easier to sample 1 LED at a time(a 3rd sampling when both are off is needed to discard the effect of ambient light). So I want to control the LEDs turning on and off sequence and asscociate the ouput with its respective sampling in LabVIEW. Is this possible? If not I would have to build a intermediate circuit with a micro controller. Thanks for your quick responses. I am really appreciated.
Where is Threshold Peak Detect VI ?
I want to use the Threshold Peak Detect vi, but can't seem to find it in LabView v6i
Re: call IMAQ DLL from c++
Richard, There are IMAQ DLLs that can be called from C++. These would be installed as part of the NI-IMAQ driver software (downloadable from this website). The installation of this software will also install a function reference manual to help you use the IMAQ DLLs. If you want to do image processing, you would also need the Vision for Measurement Studio package which would install additional DLLs for image processing. This is a separate package that would have to be purchased. If you have additional questions you may want to post additional details on the task that you are trying to accomplish so that this forum can help you to answer your questions. Regards, Jed R. Applications Engineer National Instruments
Re: write to spreadsheet file and always replace
it seems to be working. thanks. matt
Re: Tab Control will not build properly if "tab location" are on left or right.
I tried doing just that but it still didn't work for me. ??? I wonder if anyone else tried this and what the results are! Thank you Dennis, Wil
Re: Can LabVIEW work with https (not http)?
Hi, Please take a look at the document below that discusses LabVIEW and HTTPS http://digital.ni.com/public.nsf/websearch/87CC7C84AAB73BA886256DA400662672?OpenDocument";>Does the LabVIEW Web Server support SSL and https? Sincerely, Feroz National Instruments
Why is the front panel "inactive" when using event structures
I have a VI which reads in a data file and allows the user to analyze the data. This is done through an event structure in a while loop. Reading the data file happens outside of the while loop. Everything works fine until I want to "restart" the above in another while loop to view a different data file. As soon as I end the inner while loop (triggered by the event structure), the next data file is read and displayed. However, the cursor in in the "hand" mode and basically has no ability to activate buttons or move cursors. The inner while loop is iterating. Any ideas on what I might do to correct or trouble shoot this one?
Unable to change logic on parallel port
I am using Outport from accesshw with LV6.1 to control logic staes of parallel port. The port LPT1 does not repond to the program. On changing the address to LPT2 and switching the device to this port (additional PCI parallel port on the comp.) everything seems fine. Just the LPT1 wont work.. Any ideas why this might be?
7-segments like digital indicator
Does anyone know if this exist and is available for download?
Re: Handling Instrument Error States
See creating user defined error codes in the help for labview.
Re: je voudrai mettre a jour mon labview 6.1
Est-ce les donn=E9es du graphiques que tu veux sauvegarder ou bien l'image du graphique ? Quand tu parles de "lien" sur la face avant, est-ce que tu parles d'un bouton qui t'ouvrirait une fen=EAtre de sauvegarde? Je ne vois pas ce que labview 7 a de plus que 6.1 pour faire cela. Envoi-nous un exemple .
Re: 7-segments like digital indicator
martin pelletier; LabVIEW includes a font file called ni7seg.ttf, which resemble 7-segment indicators. Make sure it is installed. If not, you may need to search your hard disk (probably under the LabVIEW directory). Once you installed the font, use the font dialog to change the font of your control/indicator. Regards; Enrique Vargas
Re: Handling Instrument Error States
Imho, checking of instrument errors belongs in the recomended Prefix Error Query VI (where prefix is the instrument model). You should get the latest copy of the templates, guidelines, etc. from http://www.ni.com/devzone/idnet/development.htm";>here. Do not put any range checking in the driver VIs themselves. The instrument itself should be able to determine if a value is out of range and the driver should be calling the error query function. You limit the driver by using LabVIEW for things likerange checking. As an example, say you've a power supplu model A with a max current of 5 amps. Someone tries to program it for 6 amps and the instrument should put a message in it's error queue that is read and the programmer fixes his program. Now, model B of the same supply is released and it has a max current of 7 amps. If you had limited the current range in your driver, the driver would not be useable for the new model supply. If you follow the guidelines, you'll have a much better chance that your instrument driver will be accepted by NI if that's your ultimate goal.
Re: [W] Windows password protected screen saver causing LabVIEW to quit
Jason Corwin <[EMAIL PROTECTED]> wrote on Thu, 22 Apr 2004 09:44:16 -0700 Has anyone ever seen LabVIEW unexpectedly quit when using the password protected screen-saver? I had never seen this happen until one of my co-workers mentioned it yesterday, and then of course it happened to me. I know that I've left pure LabVIEW tests running overnight without problems, so I'm thinking it's some of the windows APIs that my coworkers are forcing me to run in the background, stuff like setting the window as top-most or getting names of open windows. Does LabVIEW crash ? Window APIs which you used shouldn't be the problem, but the way you call them could be a problem. Check the VI calling WinAPI for geting names of open windows. If the buffer is not large enough, it will cause LabVIEW to crash. Any other APIs are used? If you don't trust your coworkers, you can use the NI version - lvwutil32.zip, it can be downloaded from NI site. George Zou http://gtoolbox.yeah.net _ FREE pop-up blocking with the new MSN Toolbar get it now! http://toolbar.msn.com/go/onm00200415ave/direct/01/
Re: How can I eliminate spaces from a file?
Check in the online LabVIEW help under "Backslash ('\') Codes Display"
In "\" Codes Display, byte values/characters in the string which are
non-printable appear in the form of "\xx" where xx is the hex value
for the byte/character =85
with a few exceptions which haven't changed since LabVIEW v1 or v2
(since ASCII code hasn't changed):
\r for \0D (Carriage return), \t for \09 (Tab), \b for \08
(Backspace), \n for \0A (Line feed), \s for \20 (space), \\ for \5C
("\" character itself).
Type "\20\0A" into a string control that's config'd in "\" Display,
hit enter and it'll change itself to "\s\n".
A string "000D 2001 4142 FF1C FA26" in Hex Display
is "\00\r\s\01AB\FF\1C\FA&" in "\" Display
The usefulness of "\" display is apparent if you ever need to have a
string constant of just "\s" on the block diagram.
Re: Running VI from another VI
Julien and Shreesha, What I meant by 'Program 2 has to be open" is that Program1 will run Program2 dynamically, but will not open its front panel. Program1 doesn't launch the front panel of Program2, it just runs Program2 in the background. To actually see the Program2 open, and be able to stop it by clicking on the Boolean on its front panel, you have to use the FP.Open property node, or have Program2 front panel opened before clicking on "Lauch Progam 2" boolean in Program1. Zvezdana S.
Re: Tab Control will not build properly if "tab location" are on left or right.
Yes.
Re: How can I eliminate spaces from a file?
That did it!!Thank you so much!! I had version 6.1 so I could not see your example but, your step by step instructions were so helpful THANK YOU!! Molly
Re: starting a terminal
If you posted this question to the CVI forum instead of the LabVIEW one, you would probably have a better chance of locating the examples you want.
Re: functional circuit test
If all you want is frequency, you'll probably be okay. Depending on frequency, wiring type (twisted pair, coax, etc.), other types of measurement such as rise time or amplitude might not be so accurate.
Re: Need Help: How to design USB Driver for USBN9603
Actually, if the information is available, the development of a VISA driver can go pretty quickly. A coworker designed a USB board and got some basic communication done in less than a day I believe.
Re: [W] Windows password protected screen saver causing LabVIEW to quit
Return Receipt Your Re: [W] Windows password protected screen saver causing document LabVIEW to quit : was Hamid Yazdi/Plymouth_MI_US/Federal-Mogul received by: at: 04/23/2004 09:08:55 AM EDT
W: (DOS-Like-) key control : Ideas wanted
Hi all, I had at least two customers that wanted to have a keyboard control for a rather complex LV app (ECG analysis tools). Such like old 'Wordstar' or Word3 had. For the younger ones: pressing dedicated keys on the keyboard activates special functions under specified circumstances. For example, the key used to be 'one (line) up', 'one left', 'to the left border' and so on. JUST that key did that, meaning there was no or mouse click or anything else needed neither inbetween two of such key strokes nor after the last one. I had tried several attempts starting with LV 5.1 and none of them really satisfied me nor the customers. Don't want to bias you with those attempts... Has anyone of you some ideas or even better some proven concepts or code to share? Any ideas are welcome! BTW, There are better UI concepts for most UIs, but if there are literally 10th of different actions availabel that must be performed quickly and sometimes many of them, then such kind of an UI is still usefull. Takes as few actions as possibel and can be quite quick. In this special case a 96 channel ECG was transformed to a voltage mapping onto a cube around the heart. This cube is displayed from two opposide views, where the view angles must be changed. The voltage levels of different curves must be changed, curves added/deleted, some algorithms for the mapping or potential adaption are to change and so on. Greetings from Germany! -- Uwe Frenz ~ Dr. Uwe Frenz Entwicklung getemed Medizin- und Informationtechnik AG Oderstr. 59 D-14513 Teltow Tel. +49 3328 39 42 0 Fax +49 3328 39 42 99 [EMAIL PROTECTED] WWW.Getemed.de
Re: [W] Windows password protected screen saver causing LabVIEW to quit
Jason, My experience of "screen-savers" is to avoid them like the plague! Operators of my apps are instructed never to invoke them, the computer is there to run the rig/collect data - not provide a fancy screen show! If security is the issue, then can you password protect the critical areas of the application, e.g. calibration mode? Regards, David Hooper Engineer, Instrumentation & Plant Automation Shell Global Solutions (UK) Cheshire Innovation Park, P.O. Box 1, Chester CH1 3SH, United Kingdom Office: +44(0)151-373 5443 Fax: 5843 Mobile: +44(0)7776 464611 Email: [EMAIL PROTECTED] Internet: www.shellglobalsolutions.com
Re: Slow serial communications using VISA Read
I'm surprise that you're seeing this performance hit - can you attach an example? Implementation methods will greatly impact the performance of VISA read - for example, do you read 1 byte at a time? I know from apps I've written with VISA that I can sustain data rates much higher than what you're seeing. An option is to use queuing - you may wish to have two processes - one reads via visa (over and over in rather large chunks) and stores it in a queue, and the other actually performs the data processing.
Re: Running VI from another VI
Hi Shreesha, it should work, but I only have an FDS edition of LabView so I just can't try it. The thing is that if you've got an exe, you have to give the correct path for program2. This path can be different in debug mode and in an exe file. I didn't really understand what Zvezdana meant : "Program 2 has to be open". You only need to tell program1 where is program 2 on the disk and that's all. Hope this helps ! Julien
Getting data type of cluster elements
How do I get the data type of a cluster element. I know how to tell if it's a string/number/etc by casting it to GObject and then getting the class-ID, but how do I tell the difference between an EXT,DBL,SGL,etc... There must be some other property? Perhaps I have to cast it to a numeric and then there is a type property? Running LabView 6i. Thanks.
Can I run Labview or CVI program withoug engine installed
I have some questions about running Labview or CVI programs: 1. Is it possible that I can run a Labview or CVI program in a computer that doesn't have corresponding engine installed? Sometimes I need to run such a program in another computer, but I don't like to install the engine just for that program. 2. I have seen some people mention here "to create an installer when you build the executable". Is the "installer" an option of exe builder in Labview or it is another tool like exe builder? 3. Can I run an exe program built by Labview 6.0 on a computer with engine of Labview 7.0 or higher installed? Thank you very much.
Re: Guinea Pig VIs for NIWeek Session
> Most of the applications I've written have turned out less then I > anticipated (they're still ok, imho)... Is there a maximum size of the > application? (Would 600 vi be too much?) > > Is it a good idea to do an improvement session in the newsgroup? NIWeek is > just too far away for me. > I guess 600 is OK if you can break things up and get it to me in emails. Otherwise we can do it through an ftp site. As for doing it across this list, it will be somewhat limited in bandwidth compared to an interactive demo, but if your guinea pig is chosen I'll figure out something. Of course it won't be very anonymous if only one is done here, and you are the only one that asks for it. Anyway, we would gladly accept your app, especially if you can be specific about any problems you ran across. And after NIWeek, I think the slides are usually available on the ni web site too. Greg McKaskle
Why can I sometimes paste text into a revision history dialog box and other times cannot?
Why can I sometimes paste copied text (from another VI's revision history, for instance or from anywhere else) into a revision history dialog box and other times cannot? All versions of LabVIEW! It's something like the control key becomes diabled. I've noticed the same thing when saving many VI's at once, some will let you paste into revision history and others will not. Aren't all VI's created equally when it comes to revision history? All versions of LabVIEW since 3 have plagued me with this problem.
Re: The names and values out of Cluster
Thanks, Dickens What I wanted to do is to find the general way to extract the names and values of the elements IN A FORM OF STRING to save as the text form for any cluster. Untill now I have saved the Cluster by using Flatten TO STRING but you know its form is binary so I can't read that unless I did UNFLATTEN FROM STRING. It is impossible to get the data back alive when I change the cluster form and lose the previous form. That's why that I thought a way to save in a text form the names and values if necessary. I have a lots of clusters and have to unbundle and do something one by one to save the names and values. In a programming perspective, it is very inefficient and annoying. Thanks
RE: Subpanels?
Hi Additionally: - Blinking does not work in subpanel (bug reported to NI and confirmed) - Defer panel update does not work (unconfirmed) PJM Andreas Nilsson <[EMAIL PROTECTED]> wrote: Hi, I discovered the following when using sub-panels for the first time in an app: 1. Key navigation is deactivated. 2. You cannot right-click on a graph to turn on/off the Plot Legend, Scale Legend etc. (On an NI Days presentation on sub-panels and other new stuff, I asked if there is a list of things to consider when using sub-panels but there was not such a list.) Good luck! /Andreas - Do you Yahoo!? Yahoo! Photos: High-quality 4x6 digital prints for 25¢
Re: Using GPIB to talk to HP4083A Switching Controller.
I have also posted the zipped file (BCLioness.zip) to the incoming folder of ftp.ni.com. Lori.
[W] Windows password protected screen saver causing LabVIEW to quit
Has anyone ever seen LabVIEW unexpectedly quit when using the password protected screen-saver? I had never seen this happen until one of my co-workers mentioned it yesterday, and then of course it happened to me. I know that I've left pure LabVIEW tests running overnight without problems, so I'm thinking it's some of the windows APIs that my coworkers are forcing me to run in the background, stuff like setting the window as top-most or getting names of open windows. Jason -- Jason Corwin [EMAIL PROTECTED] (858) 592-4025
The names and values out of Cluster
I'd like to take out the names and values of the elements in a cluster in a string form without unbundling. Acutally, it is very annoying to unbundle and change into string when a lots of clusters should be used. Thanks
Re: Can't open excel file after saving and closing excel with activex
It is critical when using ActiveX with Excel that ALL refnums be properly closed when they are no longer used. Just a single refnum left open will cause the exact situation that you describe. Typically, but not required, the refnums will be closed in the reverse order in which they were created. Here is a good sequence: Open Application ref Property Workbooks ref Open Workbook ref Close Workbooks ref Select Sheet ref Select Range ref Write Value2 to Range Close Range ref Close Sheet ref Save Workbook Close Workbook ref Close Application ref When you have properly closed all refnums, the problem will disappear. Michael Munroe Certified LabVIEW Developer www.abcdef.biz
Re: how to control vna via agilent usb-gpib interface
Hi Simon, see this link, maybe it is helpful for you. http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101&RNAME=ViewQuestion&HOID=50650008007371&ECategory=Instrument+Connectivity.GPIB TN
Re: Edit "Write LabVIEW measurement file" header
Hey Bernd here are the steps to finding the VI Ex_headertosprdstr.VI 1.Place write LVM express VI on block diagram. 2.Right click on VI and select open front panel, then select convert and this will open up the write LVM front panel. 3.Go to the block diagram of the Write LVM and there will be another express VI in there called EX_subfilewrite. Open its front panel and go to the block diagram. 4.Then inside the inner case structure (false) ther is another vi called write data all. Open that up and go to the block diagram. 5.Then inside the inner case structure (true) ther is a smaller case structure (true) and inside that you will find the Ex_headertosprdstr VI open the block diagram and modify as needed and save under different name so as not to corrupt the original vi. Hope this helps you out. Joe
Re: which is better for labview - 2000 or XP?
Hi GSmith99, I have a personal preference towards Win2K. I found it more stable than WinXP (both Pro). However, I must admit that I have deleopped more LV7 code on XP and more LV6.1 code on 2000. Use the search engine and do a search on comments concerning LV7 and see the feedback that people gave concerning the two OS. When measuring pro's & con's between 2K and XP, try to determine if the new security features in XP will impede your work. For instance, I am using a Dual Parallel port. In Win-2K I can change the address for the ports... In Win-XP I cannot... I still have 2 thumbs up for Win-2K... I cannot say the same for XP.. But many may tell you that it is my personal opinion and you did ask, right ;o) JLV
Re: custom pulse train generation
Dave, Here are links to the user manuals for the PCI-MIO-16E-1 and the BNC-2110. These manuals should help you understand the signal connections a little better: http://digital.ni.com/manuals.nsf/websearch/06F1C9FB0D0BA5C286256C010057461B?OpenDocument&node=132100_US http://digital.ni.com/manuals.nsf/websearch/7A862014CCE0CA0486256D3B005CE8DE?OpenDocument&node=132100_US Regards, Bill B.
Re: editing analog waveforms (amplititude)using mouse
Cheers mate ! That definately helped ,I'm very please with your hand in this.By the way have you come across any other graphical waveform editing tool where I can adjust the amplitude of analog waveforms on a timeline basis ,with functions like copy & paste,adding noise and things like that.If so please let me know even if it's a different program from labview.Cos a client of mine doesn't want to do editing the hard way.He wants to edit the waveform by drawing.I would be very grateful for your advice. Thanks Rajan
Re: I'm haveing a problem saving my test results to excel using the report generation toolkit.
After the "Save Report to File" vi, dispose the file reference by using "Dispose Report" VI and wire "True" to "Save Changes?" input. -Joe
Re: Using Numeric Integration.vi: Is this correct?
This is an extremely good point and I need to contact the authors of this article who first used the Nonsymmetry coefficient and determine the correct usage. I guess the reason I assumed multiplication is because the value of fcc at (tau_max - tau) over the period of the integration can result in a lot of values that cannot be evaluated because tau_max - tau will be negative (egs. fcc(-10 usec)) and the correlation fx produced I believe starts at time = 0 and proceeds positively). What do you think? But I will contact them. Sincerely, Don
RE: Subpanels?
Hi, I discovered the following when using sub-panels for the first time in an app: 1. Key navigation is deactivated. 2. You cannot right-click on a graph to turn on/off the Plot Legend, Scale Legend etc. (On an NI Days presentation on sub-panels and other new stuff, I asked if there is a list of things to consider when using sub-panels but there was not such a list.) Good luck! /Andreas
Re: New Zealand NI Support ( was Buying LabVIEW abroad )
FYI: Here's the official standpoint from the NI Oceania Branch regarding their support in New Zealand: > The main reason for the price difference is the local support and services > provided. This includes, phone and email support, and on-site services via > the local FSE. Basically, this is what you stand to lose should you > purchase direct from the US. For the NZ case that FSE would be me! Mihai > was accurate in that at the moment, NI cannot allocate a branch in NZ. > However, it's not purely because of the size of the market but more along > the lines of manpower. As you know, our previous employee decided to go in > another direction and hence left us a man short. We decided that I try to > handle the territory along with a part of australia. The next goal is to > reestablish an NI branch in NZ. That said, we here in the Oceania branch > recognized the price discrepancy and hence recently had a 15-30% price > reduction for both countries to bring the prices down more along the lines > of US listings. NI Oceania also currently has no plans to streamline phone > support to SSP customers only. > > As the FSE, I am in NZ regularly to service my customers. I have also > established two Alliance Partners NVSI and Nightside Test Design to service > the area when I'm away. If there are any concerns about my region I'm more > than willing to listen!!! > > Thanks, > Archival Garcia > Field Sales Engineer > P.O Box 382, North Ryde, NSW, Australia 2113 > Phone: +61 2 9889 1033 > Fax: +61 2 9888 6611 > Email: [EMAIL PROTECTED] > Web: www.ni.com/australia, www.ni.com/newzealand > Support: www.ni.com/ask > Freecall (Australia only): 1800 300 800 > Freecall (NZ only): 0800 55 33 22 > Mobile (AUS): +61 419 883 419 > Mobile (NZ): +64 21 64 5869 >
RE: API Serial Functions
>From having a quick look through the license agreement, it looks like you can distribute the DLLs (and no, they don't require registration) freely, as long as they are part of your professional application (eg: no redistributing just the DLLs, or including any of their source code, or as a part of a LabVIEW serial toolkit - bugger!) --- EULA 1) This is a private email, and although the views expressed within it may not be purely my own, unless specifically referenced I do not suggest they are necessarily associated with anyone else including, but not limited to, my employer(s). 2) This email has NOT been scanned for virii - attached file(s), if any, are provided as is. By copying, detaching and/or opening attached files, you agree to indemnify the sender of such responsibility. 3) Because e-mail can be altered electronically, the integrity of this communication cannot be guaranteed. > Subject: Re: RE: API Serial Functions > From: <[EMAIL PROTECTED]> > > ...I have just started developing with the MarshallSoft library, but it does appear > the DLL functions without being registered. It is my understanding that distribution > is free of royalties. > > Allen Weekley
Re: Change Colour of Chart Frame Programmatically
Jaegen, To change the frame color programmatically is not possible I think. You can only change the plot background, the plot or the various text colors. Sorry Urs Urs Lauterburg Physics demonstrator Physics Institute University of Bern Switzerland >Hello, > >Perhaps this has been answered/discussed before, but I just found this >problem: > >It seems I am not able to change the colours of a waveform chart's frame >(the normally grey area around the outside) in LV6.1 (Win 2000). I've been >through every property in its property node, and can't find one that >pertains to this. Is this really the case? There's a "PlotAreaColors" >property, but this changes the colours of the Plot Area (the middle area >where plots are plotted), not the frame. > >I can easily change FG and BG colours with the paintbrush tool during >development, but I want to change them at run time. > >I could add a decoration or large boolean underneath it, but I'd prefer to >not have to do this. > >Any thoughts/hints/suggestions? > >TIA, > >Jaegen Milley
Re: 7-segments like digital indicator
http://members.lycos.co.uk/sgctek/
Re: spectre fréquence sous labview
As expected from the behavior you described, you are "growing" your array point-by-point by adding a new element at each iteration. Doing this, you are changing the frequency resolution of your spectrum and therefore can not directly compare the result from one iteration to another. You may consider using the Point-by-point analysis VIs instead. There are located in the Analyze>>Point-by-point palette.
how to control vna via agilent usb-gpib interface
hello Labviewers, I'm trying to control a vector network analyzer (at8722ES) using the agilent USB-GPIB interface 82357a and Labview 7. But the devices and the software don't communicate with each other. I've read carefully through these postings: http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101&RPAGEID=135&HOID=5065000800B8C2&UCATEGORY_0=_49_%24_6_&UCATEGORY_S=0&USEARCHCONTEXT_QUESTION_0=8722es&USEARCHCONTEXT_QUESTION_S=0 I downloaded the vi from the given link, but had no success controlling my vna. Can't I use these vi with my USB-GPIB interface? I would be grateful for any hints how to make the three systems work together. thanks in advance Simon
Re: use start trigger with pci 6602 with driver ni daq
merci*
Re: Inherited reentrancy?
"In other words, does the reentrancy get passed up the chain?" My understanding of reenetrancy says it should. I never used it like that before, but I created little program that duplicates the scenario you put in the post, and it worked correctly, as I expected. I passed data thru terminals to get the updated values to the main vi.
Re: How do I get a print dialog window ?
I want Labview functions Joe, any suggestions ?
Edit "Write LabVIEW measurement file" header
Hello everyone, how do I change the header of the Write LabVIEW measurement file VI? For example I want "PN, Lot#, Station ID" instead of "Writer_Version, Reader_Version, Separator" and only "Std Dev" instead of "Collected (Std Dev)". Thank you!
Re: Slow serial communications using VISA Read
Thanks, give me a couple of days to see if I can get an answer.
Re: Slow serial communications using VISA Read
Let me take a look at this - in the mean time, what brand hardware are you using?
Re: Unable to change logic on parallel port
Thank you for your response. It is certainly one of the things i checked, but finally this is how the problem was solved, which i would like to share for anyone else who might have the same experience.. The BIOS setting for LPT1 was set to bidirectional, since i was successfully using this program on a previous computer i checked the BIOS setting on that PC and it was ECP, changing the LPT1 to ECP in the BIOS did the trick although i am not sure why! I would welcome if anybody can explain the details... Thanks
What can cause the timing of a program to change?
I have currently written several programs using LabView 7. In these programs I have loops that are written to read data for 10sec(200ms wait 50 loop iterations). I have run and tested these many times with no problems. When I used these programs on the same computer, but in a different facility the timing was completely different. Instead of running for 10 secs. the program ran nearly 50 sec. Any ideas?
Re: Necessary to make strange tweaks to my array data pointers when calling dlls
Thanks David, Rolf, and Greg for all the input on this rather esoteric topic. I still have issues regarding this topic, but I don't know that I can formulate them into pointed questions. In any case, the dll calls work, and that's what matters in the end. What I DO know is that - thanks to you guys - I definitely know more about what's going on at the assembly level when a dll is called than I did when I started this thread. Gentlemen, you rock. Four stars all around. Nick
Re: indicator refresh
I took a look at your code. I am a bit confused. I don't see the case statement that you referred to. Is this a subvi that is called in the case statment? There aren't any inputs or outputs in the icon's connector. If this is a subvi, the problem may still be in the case statement that calls this subvi(?). A couple things I noticed: 1. You update your indicators regardless of the TCP Read Error output. If you have a TCP Read Error (as your posted code does) the text string output of the read would be an empty string. That is a possible reason for the indicators resetting to zero. 2. You'll want to use the TCP Close Connection when you're done with the vi (or subvi). Hope this helps. If there is a higher level vi that calls this one, post it so we can see what you're doing. Tim
Re: permanently relink subvi
Right click on the block of the vi you changed, select "Replace with", then select the file you altered in the pop-up box. This will replace/re-link the modified vi.
Re: Anyone know how to generate PINK noise in a Labview VI?
If you have the Sound and Vibration Toolkit 2.0 or later, there is a VI in the Sound and Vibration>>Generation palette that directly outputs a pink noise waveform.
[L] Firewire IIDC (DCAM) cameras in Linux?
Hello info-lv'ers, Anyone write any LV code for communicating with IEEE1394, IIDC-compliant (aka DCAM) digital cameras in Linux through the libraw1394 or libdc1394 shared libraries? Regards, -Jim Kring
Re: Unable to change logic on parallel port
If you have a printer installed on your machine, perhaps it has "grabbed" the port and it is inaccessible to other programs. Try uninstalling your printers to see if this is the case.
Re: how do I de-multiplex and sample signals that shares 1 input analog channel?
There will be very small difference in the sensor output depending on which LED is on, and when they are both off, the output will have a distinctive smaller voltage range. So if this is not doable in LabVIEW, I need to use an intermediate circuit that will control the LED turning on/off sequence, split the 1 output line into 3 analog input channels to the DAQ board?
Re: Using Numeric Integration.vi: Is this correct?
Per one of the authors: "As for the nonsymmetry coefficient, this integral is just a measure of the mirror symmetry of fcc around taumax. It would be zero if perfectly symmetric. The integration should really be from 0 to +infinity, but as before, outside of some range of tau, both fcc(taumax-tau) and fcc(taumax+tau) (these are functional evaluations, and not multiplications) will both go to zero. So the integral may be appropriately truncated." So you were correct and I thank you for pointing this out. As explained, this makes perfect sense. Thanks again, Don
permanently relink subvi
I made some changes to a lower-level subvi and then changed it back..but now everytime I open the higher-level vi's, I would need to go back to that subvi and relink it in every VI where I called that subvi. How to do this permanently so I won't have to do that EVERY time I open the main vi?
Re: how do I de-multiplex and sample signals that shares 1 input analog channel?
Maybe you could explain exactly what you need to measure. If you have to verify that only one LED is on at a time, then I don't think you can do it with only one sensor or only one that can't differentiate. LabVIEW has nothing to do with it. If your aim is to simply turn the LEDs on and off in a specific sequence and don't care much about verifying exactly which one is on then its doeable.
