hello friends !
i want to convert to LabVIEW NXG but i have some questions , can i work with same Features for The old generation from labview and can i use the same Libraries and Toolkit like control design and simulation or linx (arduino)
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labVIEW NXG with arduino
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Why some function nodes are gray-ish in color in block diagram?
In LabVIEW 2016 I see that few function nodes are gray tint colored but in the function pallet I see them dark colored. Why does this happen? For example, in below image see that TDMS write from the function palette is dark color where in block diagram it's grayed.
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Waveform chart real time plotting
Hello everyone,
I am a new LabVIEW user and learning the software by following some books and other online stuffs. My doubt is regarding waveform chart, i made a simple program using random number and plotting it on waveform chart. As plot is being generated over a period of time the values on X-axis keep changing. Is there a way such that i can make a program such that my X-axis is always starting at t = 0 and even if run the program for 2 hours the chart should be showing the values from 0 seconds to 7200 seconds.
I know that a waveform graph can show this. But i want plotting in real time
Thank you
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Simple way to fully remove all traces of LabVIEW's serial number from a Windows machine
Hello,
According to https://forums.ni.com/t5/Real-Time-Measurement-and/Recommended-way-to-deploy-to-a-Windows-based-IC-3173/m-p/3671983#M18470 the recommended way to develop an application for a Windows-based NI Industrial Controller is to install LabVIEW on the controller itself. At the end of development, I should deactivate LabVIEW before handing the controller to my customer.
However, deactivation still leaves the serial number in the Windows registry. So, I'll need to either manually delete the serial numbers from the registry, or uninstall+reinstall LabVIEW to overwrite the existing serial numbers.
The manual deletion method is somewhat dangerous, and the reinstall method is somewhat tedious. Is there an easier way to delete the serial numbers?
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How to do finite sample of angle position
I am using a PCI-6601 to do a finite sample of angle position. It must be sampled with an external clock according to Labview help. But I dont know the exact samples I should acquire, and dont know what time the external clock will stop. How can I get all the samples without a timeout error after the external clock stops ?
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Large data Application
Dear Community,
I have a requirement to develop a program with large datasets. Normally when working with small or medium datasets I use clusters that contain all data needed and that are available in each case of my state machine using shift registers.
I am thinking about what alternatives to use instead of shifting clusters with large data sets in the new program. I was thinking about using FGV to set and get data values or even go object oriented. I am new to OOP. One question I am asking myself is:
If I define the class data to be the large cluster data then what is the best way to implement class methods to read and set the values of the class data cluster. Bearing in mind that sometimes i just want to read/update one, another time up to 300 or 400 values.
Appreciate your feedback.
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sampling signal in labview?
How i can to sample a signal in labview?
For example if i have a signal in array of data (dbl) and i want to sample this signal how i can do this?
Thank you .
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Labview 2014 with Labview 2016 License
Hello guys,
I purchased a Labview 2016 students license, but it seems that I have to use Labview 2014 to connect it to my Raspberry Pi via LINX.
Is it possible to install Labview 2014 witch my 2016 students license?
Or is there any other possibility? suceeder of LINX or something similar?
Best regards and excuse my bad english,
Felix
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Indicators change too fast
The numeric indicator changes from a number to 0 too fast for me to see. Is there a way I can store all the numbers? Thanks
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Prepend text in text file
Hey guys
i'd like to create a log file, however i have some problem to display log line by line, most recent first.
how can i add text without loosing previous datas ? Solved thanks to the end of line constant
More how can i add a scrollbar on the right when the text box become too small ? Ok, so just right click -> visible items -> scroll bar xD
nvm, all problem are solved 
Thanks in advance
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How to calculate LDPC minimum distance?
Parity matrix H size is 48X96 at half rate, where k=m=48 and N=96. How to calculate LDPC minimum distance for matrix 48X96 in order to detect number of error bits and correct the number of error bits.
Any source code available?
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Synchronization of VSA and VSG of NI PXIe-5646R results in a fixed non-integer sample delay
I am attempting to synchronize the phase of the analyzer and generator of a NI PXIe-5646R using niRFSA and niREFSG with the following resources:
- http://zone.ni.com/reference/en-XX/help/372058N-01/vstdevices/5646_rfsa_gsynchronization/
I'm using the PXI_CLK10 of the Chassis backplane as the reference clock for both RFSG and RFSA. The center frequency is 836 MHz and the IQ-rate is 160 MHz. The LO_in and LO_out terminals are correctly connected. The RF_out and RF_in are connected with the shortest possible wire (I would reckon about 5 cm).
The LabVIEW code seems to be correctly implemented as succesive measurements result in the exact same phase delay between the output of the RFSG and the input of the RFSA. The phase delay between RFSG and RFSA is however an non-integer number somewhere between 154 and 155 samples (with a sample being equal to 6.25 nanoseconds). The 5cm wire is unable to explain this huge sample delay.
Any ideas on the source of this sample delay? Or even better, on how to negate it without post-processing?
Thank you for your time.
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Levenberg-Marquardt, error
Hello all,
I'm currently trying to implement a nonlinear curve-fit routine in LabView (Nonlinear Curve Fit.vi, Levenberg-Marquardt). I'm trying to find a best fit for a given exponential decay, and the fitting model is passed to the Nonlinear Curve Fit VI through a VI. However, I don't want to implement the model as simple function, but instead I want to describe the model with a Runge-Kutta ODE solver. I do that, so I can later on implement more complex mechanism and models that do not have an analytical solution.
When i try to run the optimization the Levenberg-Marquardt algorithms runs a few times, and then returns "Error -20041 Analysis: The system of equations cannot be solved because the input matrix is singular."
This error seems to occur quite often, but the other topics here couldn't solve my problem unfortunately.
Any suggestions on how to solve the problem are highly appreciated ![Smiley Happy]( "Smiley Happy")
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FPGA I/O question
Is there a performance difference between reading several channels on a C-series module from a single FPGA I/O node, versus sending an array of I/O channel constants into a FOR loop where each I/O is read once per iteration (disregarding the FOR loop overhead - I am more concerned with scanned channel / read timing on the module)?
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draw flattened pixmap - strange colors after some image manipulation
Hi there,
I have some unexpected results when plotting a 2D-Array as a flattened pixmap. The problem occurs in two selfmade sub VIs and a test VI I made, to do some basic image processing with a video signal I get from a IDS camera. In detail, I an averaging function over some frames and I also want to be able to downsample each frame.
The averaging:
I store the luminance* values for each frame in a shift-register and summarize over N frames. After that, I divide by N to calculate the averaged luminance values.
The downsampling:
My major goal is the implementation of a gaussian pyramide, but for starters, I have to smooth the image before downsampling it. I therefore convolve the 2D-Array of the image with a low-pass filter.
In both cases, the image looks something like the attached file "pinhole_after.bmp". Note: "pinhole_before.bmp" is the blank output image I get from the camera; "pinhole_after_sharpening.bmp" is the output, when I don't convolve with a lowpass filter but a high-pass filter.
For my understanding: The low and high-pass filtering has a strange behavior. The lowpass makes trouble but the highpass not. I don't understand why.
Up to now I looked into the IDS VI and got a better understanding of the color depths: The camera has a ~10bit output (may be something else) but the IDS VI does something and I gives me a 24/32 bit output. (the pixel values are stored in a 1D-picture array). With further code from IDS I get a 2D-Array, wich should have 24-bit color depths.
Then I looked into the "flatten pixmap.vi" and got looked into the code. It looks like the VI splits the luminance value of the 2D-Array into RGB, then does something **magical** and gives me values, which are not identical. (Note: In a 24-bit image, each RGB value has to be equal to get a shade of grey, but this is not the case. The output looks something like this: 24, 201, 231 but it should look like this: 24, 24, 24 or 201, 201, 201, or 231, 231, 231. If I look at the same values for the original image from the camera, I really get the expected identical values, but not after I do some math).
So, my question is, where is my mistake? If someone is interested in helping me, I can deliver more screenshots of probes and also the VIs, but at the moment, I described everthing I know. Thanks for reading.
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Why does receive CLFN only return the first data in the buffer, but not the second?
I have two separate loops in LabVIEW. The IPv6 server loop is running at 50 Hz and the IPv6 client loop is running double the rate at 25 Hz. This means that on average, the client calls my send subVI twice, every time the server calls the receive subVI.
When I run my program, the server always only receives the first message that the client sends and not the second message. However, what I do not understand is that the server's receive subVI then says that it has received a total number of bytes equal to Client message 1 + Client message 2.
For example:
Client sends message 1 = Hi
Client sends message 2 = Bye
Server receives message = Hi
Server number of bytes received = 7
What's going on here? I'd like to just receive the string 'HiBye' so that I can parse out separate messages with EOL characters.
Thanks.
Here are some screenshots of my LabVIEW program and C shared object library. Let me know if any other screenshots may help.
C Library Code:
Main VI (Server top loop, Client bottom loop):
Receive subVI:
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Feedback Control Advice
I'm trying to create a closed loop for my system, but I'm having some trouble figuring out how to implement it. Currently, I'm just doing something simple where I command a current (gets transformed to voltage by a linear relationship), and sends this to the power suppply. The power supply then responds with a current. For example, if I give it an input of 1A, I will read 0.97A from the power supply. I have also added a range to check whether the output is within 1% of the input. If not, then I update the input with the error term to send it more current (i.e 1A actually sends 1.05 to get closer to the 1A output as expected).
I'm having some issues figuring out how to do this properly, as I want the user to be able to manually change the input current and my control system to respond accordingly. Currently, I believe my control system and input current are interfering with each other causing unstable results as they are "competing". Please let me know what you suggest I change. Thank you
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Conversion
Please help me to convert this file from LabView
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How do you write a block parameter value in Fieldbus
I'm trying to write a LabVIEW interface to communicate with Fieldbus devices. I have figured out how to navigate down the chain of interfaces to devices to blocks to whatever else is between me and the data I'm trying to get and now that I can read the parameters, I want to be able to write them. I took my best guess, but when I call the FF write block object (by name), the vi generates some internal error for which there is no description. I've attached a picture of the code. Anyone know what I'm missing?
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Wire error stating FIFO Data type is 1D array
I have a Host to FPGA DMA FIFO with data type defined as U32. On the Host, when I try to wire a U32 constant to the Data field in the Invoke Method block for the FIFO write, I get a wiring error stating that the sink type is a U32 1D array. Why is this happening when a FIFO can't use arrays as a data type? Attached a screenshot of this error.
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