hi,
i want to make a chart recorder which display incoming data with a speed of 125 mm/s and 25 mm/s .. so how can i achieve this ?
↧
waveform chart
↧
Embed OpenG into Labview Project?
Hey,
I would like to use OpenG inside my Labview Project because of several advantages. The project is supposed to be installed on some production test facilities, where mainly the build is being run by the operators.
In case of bugs I would like to have the project folder installed on the test facility aswell, to make fast bugfixing. Now the problem is, that making sure to have OpenG installed by the IT on our test facilities is always a great pain and very time consuming. So I am looking for other ways to get the OpenG there. Best would be, if certain OpenG functions could simply be embedded into a certain project.
I have tried this by simply copying the appropriate OpenG VI, but I faced very soon, that the appropriate OpenG Vi has a lot of OpenG subVis that are dependent.
Is there any way to embed OpenG functions or even the whole library properly into a project (just like a Labview Library or something).
The only way I found in the forum is the use of an installer, but that would again need IT support and that could get exhausting again:
https://forums.ni.com/t5/LabVIEW/OpenG-Package-Installer-v0-5-Alpha-Release/m-p/66263
Ok thanks a lot already!
Best Regards,
Jenso
↧
↧
how to automatically stop the VI?
It is an example of running a stepper motor. In the attached VI, after I press run button VI starts. Motor starts moving after I press the "START" button given in the front panel. But I want to stop the whole program after the value in the "CURRENT POSITION" equals the value given in the "DESTINATION POSITION" control. Please tell me how to do it?.
I am attaching the VI.
↧
Trigger event in multiple subVIs
Hi
I have an application that launches several subVIs each containing X-Y Graphs. All subVIs use a event driven Prod/Consumer framework. I would like to be able to syncronize the cursors in all Graphs, so if I change cursor position in one subVI it will change in all subVIs. Because of P/C framework I need to trigger an event in each subVI to make it work. Is there a simpler way of doing this than setting up an User Event in each subVI? I've been hoping that a Global variable could trigger events, but it doesn't look like this is possible.
Regards
Bård
↧
how to read the output of sound card(speaker not micphone)
Background: The headphone jack of my laptop is broken,and I want to use headphone to listen instead of the self-contained speaker.So I want to read the sound of the speaker, and send to cellphone.Then I can listen from cellphone with headphone.
Difficulty: It's easy to read micphohe, but how to use LabVIEW to read the speaker?
Something may be helpful:Loopback Recording
↧
↧
Multiple Analog Outputs on cDAQ
I am trying to output two different analog outputs on two channels on my cDAQ. One output is a square wave and the other is a constant voltage that changes when I press a button on the front panel. I cannot get both outputs to work at the same time. I have successfully outputted two constant voltages but when I try the waveform it does not work. The screen shot I included is basically what I want to happen and I have tried many different settings and used DAQmx vi's as well and nothing seems to work.
I am using a cDAQ 9174, and an NI 9263 AO module.
↧
Wait function alternative
Hello,
I have been using auto indexing tunnels to extract values from an array to be used for further operations. Now the problem is within the program when this auto indexing is being run all the other loops and readings are stopped until this for loop is being executed. Is there any< way to sort this issue?
Thanks in advance,
Safar
↧
Re: Tell us about your large LabVIEW applications!
Hello Joul,
I was looking for a Plugin for UML based Enterprise Architecht and LabVIEW. Can you please share if this plugin is public.
Thanks and Regards.
Ali
↧
Error 74 occurred at Unflatten From String
Good afternoon
I'm having a TCP communication and I'm obteining this error, I always do it in this way and it never report error. Can it be because i'm trying communicate many datas??
Error 74 occurred at Unflatten From String
Possible reason(s):
LabVIEW: Memory or data structure corrupt.
↧
↧
I couldn't find how to integrate CDB with DBL in front panel as a single array
Hello,
I am working with a LabVIEW example 'Matrix Fundamentals' in which I can see both DBL and CDB data types in the block diagram but both are connected as a single front Panel object. How can we make that?... I couldn't solve this. Please help me out. Thank you in advance.
↧
Non-linear curve fitting for complex data
Hello
I'm trying to do a non-linear curve fitting for complex data in LabView NXG 1.0. My model function is a transfer function of a measuring system and depends on 5 parameters, which I want to optimize.
In this forum post (https://forums.ni.com/t5/LabVIEW/Non-linear-curve-fitting-for-complex-data/td-p/1016568) I found VIs, that do such a non-linear curve fitting with complex data. But these VIs are createt with the "normal" LabView. I tried to convert these VIs to LabView NXG, but it doesn't work, because the used reference to the VI with the complex function doesn't work in LabView NXG. Is there an option to fix this problem?
I also don't found the used Levenberg-Marquardt-Curve-Fitting-VI in LabView NXG 1.0. Is there an equivalent VI for curve fitting in LabView NXG?
Thanks for you help
Basil
↧
Transitioning a legacy program from Stacked Sequence Structure - alternatives?
I am maintaining a legacy instrument control program (in LV 2011, but it was written long before that) which is essentially several nested stacked sequence structures. Each execution loop, the program reads data from external sources as well as several Boolean controls, performs a large number of checks, and finally updates the status of a bunch of external relays.
For this application it's very important that these tasks always be executed, and always in this specific order, so despite the general disdain for stacked/flat sequence structures around here I think this is their intended use case. If I were to simply put all the code left-to-right, not in any structure, the program would be one screen high and 100 screens wide.
However, this architecture makes it very difficult to constantly monitor for events such as the pressing of a button. I'd like to be able to do/check certain things programatically more than once per program loop. I'm not very well-versed in LabView, what alternatives to a stacked sequence should I be looking at? A state machine would be overkill because there's never a need to decide which state to advance to.
↧
Create Occurrence.vi replacement in newer LabView releases
Hello,
I am very new to LabView, so please pardon my greenness.
I recently was tasked with trying to update a vi we use for product testing. Only issue that I haven't worked around is what to replace the Create Occurrence.vi with in the newer releases of LabView. I have searched through topics and have made no progress. At the point now that it may make some sort of sense to install the older version just so I can see what is actually going on. LabView 2014 doesn't include the Create Occurrence.vi, I have tried wait for state with no luck. The '?' in the above vi is my problem. Any direction would be greatly appreciated. Hopefully I posted this in the correct forum.
Thank You in advance,
A Newbie
↧
↧
Linux RT startup.rtexe replacement without Network Connection
I have some systems that are running a 9651 SOM and some on sbRIO that are NOT connected via Ethernet to each other that need to have their RTEXE replaced as part of field upgrades.
We can transfer the files via CAN or Serial to the units when running the existing startup.rtexe but I don't think the running application in Linux can replace its own copy on disk while it is running. Am I wrong and the RTEXE can be replaced on Linux when the application is running?
Any suggestions on how to replace a startup.rtexe without Ethernet connection once the new file has been transfered?
↧
Synchronizing Analog Input and Delayed Digital Output (LabVIEW 2014)
I'm using LabVIEW 2014 with a USB-6363. Since I suspect that my attempt at a solution is much more complex than it should be, I'll separate what I want to do from how I tried to do it.
Objective
Given a set of U8 binary numbers and a certain clock, I'd like to, for each U8 binary number,
- begin recording analog input
- after a small initial delay, write out the binary number to a port on my device
- after a preset number of clock pulses, end analog input collection and append the data to an existing file.
I would like to repeat the above three steps for each U8 number in an array, so I end up with a file with a different series of data for each number in the array.
Implementation
I'm new to LabVIEW, and I spent a fair amount of time trying to figure out the best way to do this. I ended up trying to control each measurement "cycle" of reading, writing, and saving with one clock and handling the measurements with another (but triggering off of the cycle clock). I was going for something like this,
In my implementation, I didn't know how to change CLK 3's low time so that it encompassed a variable number of preset clock pulses in step 3, so I just made it long enough to encompass any number I might choose (1 second). That is likely my first of many mistakes.
I ended up with the following VI (which I've also attached):
which uses three DAQmx tasks, three DAQmx Assistant clocks, and a circular buffer. The circular buffer is sized to accommodate exactly one recorded signal's worth of samples, and it saves whenever one of the DAQmx tasks (CLK 3's terminal fed into an analog input on my device) detects a falling edge.
I know this is likely far too complicated for what I'm trying to do, and probably contains many mistakes. However, I figured I should ask for advice about better, simpler, or more effective methods of solving my problem before attempting to further complicate and debug my own. This is far from my first attempt, and each time I feel as if the best method of doing it completely escapes me.
Please let me know if there's anything I can clarify.
↧
Modify Event Structure to Have Continuous Data Acquisition Shown on Graphs
Hi Everyone,
I have asked a similar question before with the same VI I wrote, and it seems like I didn't frame my question correctly. I will explain it more clearly, and I am attaching my VI below.
So when I am running my VI, the graph updates every N samples. Let's say I set "Samples per loop" to 10000 and the "sample rate" to 1000, the graphs will update every 10 seconds, and the x is a 10 seconds frame. I want the graphs to be continuously updating and x (t) will increase all the time. Because I am building my VI on the basis of an example, the event in the event structure is "Every N samples acquired into buffer". And I think this is exactly why the graphs only update when it has "N samples".
Is there a way to restructure the "Event structure" to make the graphs update continuously, not every 10 secs even with a large "samples per loop"?
Thank you very much.
↧
Question about PID in FPGA
Hello guys,
Now I use PID function in FPGA to control the feedback value of my system. I only need PI, so I set D to 0. Now there is problem that after running a long time using PID, the system will be out of control. I think the reason might be the integration works from the start and keeps integrating errors, and if there is a shift for the feedback value, the integration still use the integrated value from past to now to do the control and it might get messed up? Then I try a way: reset the control output every certain time. This will prevent the integration accumulate too much, but it will cause a sudden change to the feedback value.
So now I really don't know how to deal with this.
Thanks
↧
↧
Opening separate windows for waveform charts
I'm using the Continuous Measurement and Logging (DAQmx) template to create a multichannel voltage measurement system. At the moment, I'm trying to implement having a separate window appear to display the data coming in. I'm pretty new to the queued message handler design pattern, and I'm struggling somewhat. The idea is that the user will be able to click a button in the main front panel, (like "Show Graphs"), which will then open a separate window displaying the graphs, one for each enabled channel. I've tried modifying the existing waveform chart by turning it into a Type Def, and by creating a separate SubVI, but niether has worked out.
Any help on how to achieve this would be greatly appreciated.
↧
Validating a continuous transfer function outside the simulation loop
Hi, I am quite new to labview. I have 2 questions.
1) I am modeling a certain transfer function and I would like to test it with Real signals.
I tried using putting DAQ inside the simulation loop and use the transfer function.
Result is the processing time is so slow. Is this normal? Or is there any other way to simulate a transfer function with real inputs?
2) I also tried making the CD model into System Model and validate it through SI Model Simulation.
But it seems it is not possible to construct a continuous System model by just stating its coefficients.
So my question is, is there any way to construct a continuous transfer function using the System Identification toolkit?
Please help. I am really stuck and cant move on.
Regards,
setsu
↧
Chroma 61503 Delay Problem in Labview
Hi guys,
I am trying to solve a problem related with Chroma AC Source and Labview. I want to set chroma using parameters in the excel file then I am going to measure chroma paramaeters. At the final, I want to graph measurements. But it requires 3.5 seconds for one sample and I did not use 3.5 seconds delay. I think, the source of this problem is chroma's set and measure blocks. Is there anyone who face with this problem ? This is my lecture project.
Thanks for your time and concern in advance.
↧
