Re: How can I detect if a global bolean variable has changed
Hi Mads, This is really a good help, now I hope I can solve the problem. Thanks a lot! Angel
Re: rounding problem , LV7
Hi Pawel, This is the correct behaviour for the round to nearest Function. This function Rounds the input to the nearest integer. If the value of the input is midway between two integers (for example, 1.5 or 2.5), the function returns the nearest EVEN integer. Hope this helps, Nick
Re: how to enlarge the picture at the same scale(proportion)...
Hi Pyi, To answer your first question if you alter the vi properties (right click on the front panel icon) and select window size there is a scale all objects tick box at the bottom this shouls solve this issue.The imaq question I believe is a separate package which you need to buy. Hope this helps, Nick
Why Does My Digital Read Interrupt My Digital Write When Using Easy DIO VIs?
I am using Write to Digital Line.vi to set the state of a digital line on my board, and then Read from Digital Line.vi to read the state of a different line on the same port of my board. It seems like when the READ executes, it does not maintain the state I set in the WRITE. How can I fix this? Your help is greatly appreciated.
Monitoring TCP port status
I would like to know if a tcp port is open or not. How can i do it ?
Re: save data from a frequency domain acquisition
Hello, thank you for have answered to my question but probably I haven't explain my problem very well. My problem is this: after processing the signals obtained with the accelerometers using the fft I have obtained a graph.I want to save it in a file that I can use like I want but I am not able to do it.
Re: I am looking for a indicator like a FLASH LIGH, just show my sequencies moving on.
Only problem with this is that if the program actually does stop working (hangs up somewhere), the indicator keeps animating and the user just learns to hate the lying indicator ;) This is why I curse and swear at the Windows animation of pages flying from folder to folder, which keeps running even when nothing has moved over the net connection for half an hour... or the progress bar in IE5.5 that keeps progressing even though the site is not responding or doesn't exist. Much better to relate your progress indicator to real progress in the program, if you can...
Re: 1D Array Search
I'd guess that the previous method using Search 1D Array would be faster, if your array is large...
How Can I execute an external program from my vi?
Hi guys, I want to execute a external program to use it when i called with a bottom. I want push a bottom and execute the program, like acess direct icon or so. Any help?.
Re: save data from a frequency domain acquisition
With your frequency spectrum, you have three elements, (f0, delta-f, and an array of numbers for magnitudes of each frequency bin). You can write this data to excel in the same way you write time domain data. You can even re-cluster your FFT data as a time waveform, and use the write waveform to spreadsheet functions. I am curious to learn more about your application. I specialize in rotating machinery applications for NI and would welcome the opportunity to learn more of your interpretation and expected use of the data. It may be we have even more help to offer. Hope this helps. Preston Johnson [EMAIL PROTECTED]
Re: how to close a vi automatically?
Hi Plainman, Take a look at the example I posted here http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101RPAGEID=137HOID=506500050014570100HTHREAD=87828UCATEGORY_0=_49_%24_6_UCATEGORY_S=0 I believe it demonstrates one method that you may find helpful, Ben a href=http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101RPAGEID=261HRedirected=TrueHUserId=101_3529RFORMNUMBER=6;Ben Rayner/a a href= http://volt.ni.com/niwc/common.jsp?page=products_certification_cldnode=10638; Certified LabVIEW Developer /a www.DSAutomation.com
Re: VISA Performance
It looks like the others have given you some good ideas and explanations. The is only one thing that comes to mind. Have you compared the VISA versions? The were some performance enhancements implemented in one of the VISA updates. Ben a href=http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101RPAGEID=261HRedirected=TrueHUserId=101_3529RFORMNUMBER=6;Ben Rayner/a a href= http://volt.ni.com/niwc/common.jsp?page=products_certification_cldnode=10638; Certified LabVIEW Developer /a www.DSAutomation.com
Re: Why Does My Digital Read Interrupt My Digital Write When Using Easy DIO VIs?
The usual reason this happens is because the Easy DIO VIs reconfigure your board each time they run unless you wire in the iteration terminal. Reconfiguring your board resets lines. Even if you do wire in the iteration terminal, the first time an Easy DIO VI runs it configures the whole port as input or output - clearing your previous port configuration. If you are using traditional DAQ, the best thing to do is use three advanced VIs: DIO Port Config.vi, DIO Port Read.vi, and DIO Port Write.vi. You can find these on the advanced palette or on the diagram of the Easy DIO VIs. Call DIO Port config.vi only once and configure your individual lines as input or output (assuming your board supports individual line configuration). Regards, Doug Norman
Re: enter new line in text string in saved file when appear carriage return!
try using the end of line constant instead of the carriage return. Hope this helps.
Re: I am looking for a indicator like a FLASH LIGH, just show my sequencies moving on.
Just another thought on this though... you could put the frames of your animation into a pict ring indicator and have your program increment the indicator to animate the picture as the task progresses.
Re: I am looking for a indicator like a FLASH LIGH, just show my sequencies moving on.
Agreed with your comments. Something must show real progress somehow.. JLV
Re: how does the interface to ADO drivers work?
First, I am not using the Database Connectivity Toolkit. I have written drivers that call Oracle's ADO (OLE DB) drivers directly. And the LV interface is filtering things out. For example, the documentation on the drivers says there's a method called Apppend Chunk but it's not available from LV. What I need to know is what is the nature of the interface between the ActiveX interface and code such as the Oracle drivers. Mike...
Re: modem V23 code source
mike, you seem like you are really familiar with modem communications. I am trying to have my Labview 7.0 program to answer a phone call from a cellular phone and then allow me to work with the analog data coming in. I want to do this to allow me to run labview data acquistion from the computer when i am not in the same room, hence, via cell phone. thanks Jared
Re: unable to read the frequency!
Your actual data are not accessible and the sub-VI is missing. If you could re-post your VI with time data saved as default on your graph that would be helpful. In the mean time ... few comments: - You are attempting to display Amplitude vs. Frequency on an XY-graph. However your graph data are just two scalars representing respectivelly the single value amplitude and the single value frequency. This will only give you one point on your graph. - What exactly are you trying to display? A set of multiple amplitudes vs.frequencies? The spectrum of your signal?
Re: enter new line in text string in saved file when appear carriage return!
Hi Joe, thanks, I know i should to use \n and use ain vi to search the carriage return and put \n in this place, but i dont know how get it. Any example? Regards,jose.
Re: How Can I execute an external program from my vi?
Thanks Thomas it works. regards,jose
Re: Data pass over sequence loop
Ed, i get it. Thank
Re: Clusters: How to remove the 3D shaded background?
Paint brush tool
Re: how can I allow labview to answer a call from a cellular...
I have used labview to pick up a call on a cell phone. It is easy as long as you know the protocol used. I'm sure you can do it with landline phone/modem as well. Joe
Re: Value (Signaling) property and programmatically generate value change event?
Matthew, I was a bit too enthousiastic ... 8-( Your proposal works when the VI is started by the ActiveX client, i.e. an event is generated immediately. However, once the VI runs, the value of the control connected to the Value (Signaling) property (set either manually or via the Active X client) is only transfered from the control into the property (and generates an event), if the control and property are placed in a while loop. This loop contains a wait object, such that the VI does not consume all CPU time. At that moment, the approach tends to be more polling-based than event-driven. Also, the response time depends on the wait value set in the while loop (and the time it takes to perform the actions within the while loop). Another disadvantage is that this approach will generate an event during each iteration of the while loop (generates an event even if the value remains unchanged). Please let me know if I'm overlooking something. Could you also verify what's wrong with the link you provided ? Regards. Frans.
pulse acquisition
Hi! I'm trying to build a project that measure the pulse of the heart. I have succesfully get the pulse signal into the computer through the PCI-card 6014. I have used the example VI: Cont AcqGraph (buffered).vi Now can I print out the pulse in the graph in real time but I also want to measure the frequency as a mean value every fifth second. How do I do that if I set the scan/sec and scans to read a time to 1000. I want to update my graph as fast as possible, not only every fifth second.
Re: VISA Performance
The VISA versions are the same, 6.9.3 but I was going to update it to the latest 7.1. I forgot to mention that this machine used to run NT but the hard drive crashed so I had to replace it. I was having a hard time replacing the NT so in a crunch loaded Win98. If the customer can get some down time I want to reformat again and load NT. Very frustrating!! Thanks for everyone's help.
Re: how does the interface to ADO drivers work?
Sorry, Mike You've gone beyond my immediate expertise. I'm the owner of the Database Connectivity Toolset and am only familiar with the generic ADO interface. So do you call the Oracle drivers from LabVIEW ActiveX functions or are you using the Call Library Node to go through their drivers directly at the C level? Crystal
mouse up event on a slide
it's more a comment than a question. When I clicck on a slide control and keep the mouse down, I keep control of the slide value even if my mouse gets outside the control area.it's ok for me but in that case the Mouse Up event will not work. for the Mouse Up event to work properly, the arrow must remain on the slide control. Any chance to fix it?
Re: ActiveX container disappears after vi saved and recalled
This problem was related to the MS Forms 2.0 scrollbar. After talking to NI they recognized it as a known problem but it was not posted. The solution was to use the Microsoft Flat Scrollbar Control, version 6.0. This is fine except for the time spent looking around. It would have helped if it had been posted originally.
Re: I am looking for a indicator like a FLASH LIGH, just show my sequencies moving on.
Oh I agree with that. Like it said, this is just the quick and dirty way of doing it. You have to lock up the computer to stop the animation (something which we've managed to do a couple of times). A real progress indicator is much better. Instead of just saying Please Wait on screen you can also add an animated GIF. I usually prefer functional programs over cute programs, but then, we don't program for ourselves here, but for customers. Rob
Re: enter new line in text string in saved file when appear carriage return!
Thanks Joe, Edit it is the best, I got it, run good. Regards,Jose.
Re: mouse up event on a slide
It was meant to work that way so that you have a way to abort the event if you feel like you made a mistake when clicking on the control. Just keep your mouse in the proper area.
Re: How do I synchronize two counters?
Stephen, In order to generate two pulse trains on the two counters of your 6115, then you will need to provide a trigger to start both of these counters simultaneously. The counters on the 6115 are controlled via the DAQ-STC counter/timer chip. In order to perform these operations you will need to use the more advanced counter/timer VIs in the LabVIEW palettes. I would recommend taking a look at some of the shipping examples, such as Generate Pulse Train (DAQ-STC), in order to get a better understanding of how a single pulse generation works. Also, please take a look at the following websites to get a little more information as well: Triggering Multiple Counters with a Single Pulse http://exchange.ni.com/servlet/Redirect?id=10358279 Using the Hardware Start Trigger for Single Pulse Generation http://zone.ni.com/devzone/conceptd.nsf/webmain/7B2CAD8DD522049386256802007B8B51?opendocument If you have any other questions then please let us know. Regards, Michael H Applications Engineer National Instruments
Multiple Selection Dialog Box VI Question
I've downloaded the Multiple Selection Dialog Box program and it works great, except when I add *.txt to the 'Files of type' array and then save it. I close the program and then reload it again and the change I made is not present...what am I missing? tks
Re: How to determine the maxium value of scan backlog?
Hello Jujian, Thank you for contacting National Instruments. The amount of your back log is system dependant. It depends on the computer and the applications running on that computer. To set your buffer size, simply look at your maximum scan backlog and add 100 to prevent a buffer overflow error. In your case, this would be 1000 + 100 = 1100. I hope this helps, Sean C. Applications Engineer National Instruments
Re: Multiple Selection Dialog Box VI Question
br Right-click on the 'Files of Type' array and select 'Data Operations,' and then select 'Make Current Value default.' Save the VI. You'll now not lose this on reopening the VI. iKhalid/i br
Re: Labview for a policy server?
Sheela; Check the bLinks/b page in my website www.visecurity.com. I am compiling a list about security-related LabVIEW products and information. If you (or anybody that read this answer) knows more information to add to this list, I'll appreciate if you let me know. Regards; Enrique Vargas www.visecurity.com
Sequence tunnel error
Im having an intresting problem with sending out data from a sequence. Pls dont give me crap about using sequences cause this one is absolutely necessary for the hardware to work properly. Ok that said heres the problem. I have a sequence loop within a while loop. The while loop has a shift register on it used to remember a data value from one iteration to the next. The data value goes into the sequence struct where it is modified in the second frame and is then passed out through a tunnel in the same frame. Now the sequence completes the remaining frames 4 in total. Now when the data from the sequence should be passed back to the while loop, it has the proper data type (cluster with 2 I32 intergers within) but the data in the second I32 variable has been modified. Actually its been decremented by 24. and if i enter the loop again it exits with another 24 decrement. Now this isnt the only variable i have leaving that sequence but its the only one that is changed when crossing the sequence border. All shift registers are properly inited. I am completely baffled. Im guessing that for some reason the latter frames have an effect on the tunnel value but i no idea why, nothing is connected to that tunnel in the later frames. Anyone got a clue whats wrong? Using labview 6.1 on a Pent 400.
Write hex code to pic with serial port, any example?
Hi guys, i have the hex code to write in the pic16f84 by the serial port. Have anyone a example program?. Or any advise?. Thanks, regards Jose.
Re: Failure: drawmgr.cpp, line 3443, LV 6.1
Hello Miro, Thank you for contacting National Instruments. The following link leads to a Knowledge Base concerning a similar error. It lists four possible work arounds. http://digital.ni.com/public.nsf/websearch/16CF1334D094A4F6C1256BE30074B9FE?OpenDocument If these do not solve the problem, make sure that you are using the current Run Time Engine for your version of LabVIEW. I hope this helps, Sean C. Applications Engineer National Instruments
Re: Range in MAX compared to range on DAQ card?
The input range that the DAQ card uses is based on the range that you specify in MAX for the virtual channels. MAX uses the actual specified range to apply a set gain to the inputs so that it best fills one of the available range configurations on the card. If you refer to the user manual or specifications for the 6052E, then you will see that the card can have a range of 0 to 10V and -5 to 5V. Your signal can then have a gain of 1, 2, 5, 10, 20, 50, or 100 applied to it to best fill one of the two ranges above. The gain chosen is based on that input range that you specify in MAX. Please refer to the following manual and on page 3-4 you will find a table listing the ranges and gains along with the corresponding precision of your device. http://digital.ni.com/manuals.nsf/websearch/4BF830B584C7AC8A86256C5D005C02FF?OpenDocumentnode=132100_US The following links also provide some useful information: http://digital.ni.com/public.nsf/websearch/CBA83550AB782D1C862566210061BEB9?OpenDocument http://digital.ni.com/public.nsf/websearch/DD2B6FF2BFFF216C86256E23007A2532?OpenDocument I hope this answers your question, and if you have any other questions or comments then please let us know. Regards, Michael H Applications Engineer National Instruments
Re: saving and restoring,default controls values(LV7)
If you just need to save the values there are variant based tools for this included in the OpenG toolkit, you can find it on www.openg.org. If you want to save properties as well have a look at the Property Saver Toolkit at: http://www.kshif.com/lv/index.html
Re: Optimizing network throughput over Ethernet with TCP/IP
Adding to my previous; I have gotten good results using VI server technology and using call by reference to get data. I have never attempted to push the trasfer rates you are looking at but I think it is worth a quick try. The beauty of this approach (IMHO) is ZERO TCP DETAILS (sorry) to code. Please briefly outline the solution once you crack this performance nut. I would be interested in hearing how you end solving this challenge. Ben
for hp33120a IVI driver,how to change high impedance?
I am going to use hp33120A to generate a waveform. I also need to control the impedance of it become High impedance.
Re: Sequence tunnel error
Sound like you may need to add a sequence local to pass data to the second frame? Cheers JoeDoe [EMAIL PROTECTED] wrote in message news:[EMAIL PROTECTED] Im having an intresting problem with sending out data from a sequence. Pls dont give me crap about using sequences cause this one is absolutely necessary for the hardware to work properly. Ok that said heres the problem. I have a sequence loop within a while loop. The while loop has a shift register on it used to remember a data value from one iteration to the next. The data value goes into the sequence struct where it is modified in the second frame and is then passed out through a tunnel in the same frame. Now the sequence completes the remaining frames 4 in total. Now when the data from the sequence should be passed back to the while loop, it has the proper data type (cluster with 2 I32 intergers within) but the data in the second I32 variable has been modified. Actually its been decremented by 24. and if i enter the loop again it exits with another 24 decrement. Now this isnt the only variable i have leaving that sequence but its the only one that is changed when crossing the sequence border. All shift registers are properly inited. I am completely baffled. Im guessing that for some reason the latter frames have an effect on the tunnel value but i no idea why, nothing is connected to that tunnel in the later frames. Anyone got a clue whats wrong? Using labview 6.1 on a Pent 400.
Re: How can I do second derivative for X and Y arrays
Thank you so much for your helpfulness. I'm so impressive for your modified vi. Do you have the vi that suggest me to use it to differentiate the new waveform 2 times? Thank you again.
Re: 60MS/sec- is this possible?
Three different units are being measured simultaneously, which is why 3 boards are necessary (they don't all start or stop at the same time, but they could all be on at the same time). Why not use one board continuously acquiring data on 6 channels an 10MB/s and just discard the data not needed (i.e. when a unit is not active)? Lewis Drake Process Automation Corporation Belle Mead, NJ 908 359-1011 www.processauto.com
RE: 60MS/sec- is this possible?
I have been interested in this thread - it is pretty normal for people (managers/clients) who don't actually use LV or DAQ to ask for something that doesn't make complete sense. Then the questions when quoting may be: Do I quote it straight up, even though it is kind of stupid (trying to re-address the actual problem with more sensible solutions later, and risking losing the job to someone who gets a dialog going early)? OR Do I risk irritating them by trying to make it make sense from the start (and potentially convincing them that I don't understand their application)? OR Do I make assumptions that they really don't know what they want and would appreciate a pared down solution that is both economical and effective? This one looks classic. What could possibly be the point of taking data at 10 S/s and then averaging it down to 2 seconds? Is there a Nyquist reason for this? Are there intermittent bursts of data at a frequency of 1MHz that will not be resolved at lower sampling rates? Either the spec is all wrong or something kind of odd is going on. I suppose giving more specifics abouit the application is out of the question? Mike -Original Message- From: E. Blasberg [mailto:[EMAIL PROTECTED] Sent: Tuesday, February 10, 2004 9:30 AM To: info-labview Subject: 60MS/sec- is this possible? Hi All, This may sound naive, but I have a customer who wants to sample up to 6 channels across 3 boards (2 channels/board) at a sampling rate of 10 Megasamples/sec/channel (i.e., 60 MS/s in total). Three different units are being measured simultaneously, which is why 3 boards are necessary (they don't all start or stop at the same time, but they could all be on at the same time). Currently the system measures 50KS/s/channel with no problem (plus up to 2 channels of AO). The data is averaged each second and put into a FIFO buffer which is usually 2 minutes (120 samples) long. Every 2 seconds, the FIFO is averaged (to get a running average). I should add that a GPIB data logger is read every 2 seconds for slower data. My NI rep has suggested the PCI-6115 whose specs could certainly handle this. What I'm worried about is the computer keeping up with averaging 60MS/s. Anyone have any experience using these data rates over an extended period of time (measurements can last WEEKS). Much TIA, E. Blasberg iDAQ Solutions Ltd
RE: Associate a type of file with a LV7 app
yes. In windows, hold down the shift key and at the same time right click on the file. Choose open with and then set the program that you always want windows to open your file with. I hope this is the info you were looking for. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of Dany Allard Sent: Wednesday, February 11, 2004 10:07 AM To: [EMAIL PROTECTED] Subject: Associate a type of file with a LV7 app Hi, Is it possible to associate a type of file, like *.txt with Notepad.exe, with a LV7 app. I know that LV7 have a new feature that permit to retrieve the command line used to call the app. But I don't think that would be useful for what I want to do. I want to Double-Click on my file and my LV7 app start automatically and the file is read and displayed. Thanks Dany Allard [EMAIL PROTECTED]
