We are having difficulties applying the DAQ Assistant input to our program. The program worked with file input. What other tools are needed to change input from file to the DAQ?
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DAQ Assistant Input and Output
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Ploting Time values
I have a time it takes between cycles. This is in seconds. I want to plot the time it takes between cycles to a graph. In the attached program, it will be the Seconds No Change indicator that has the value I want to plot. You click the Cycle On/Off Boolean to make the seconds reset and start counting seconds between Cycles again. I would like to plot this over time so I can see if the time between cycles is drifting with fluid temperature. This is just a simulation and has to have the cycles entered by clicking the Boolean. So the ending seconds that it took to cycle should be plotted to show history on a graph or chart. Not interested in the in between 0 and time to cycle, only want to plot the time it took to cycle so I could glance and the chart and tell if the time is changing over time.
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Word or phrase selects the proper radio button.
Hi guys,
I am having a difficult time trying to get a word or a phrase to be able to be recognized and select the proper radio button but I can't seem to figure out how to associate it. I placed a 0 for the first radio button but i get a red dot. Is this the proper way to do this?
I apologize for the seemingly simple question but I want to make sure I am doing it correctly.
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Script Error when click on Find Example in LabVIEW Help
Whenever I click on Find Example anywhere in the LabVIEW help, I get the following script error and the example does not open.
"An error has occurred in the script on this page. The value of the property "openProj" is null or undefined, not a Function object"
It works fine on a different computer, so I located the example file and verified that it does exist on the problem computer.
The separate Example Finder tool (Help->Fine Examples...) works ok (opens examples) as well.
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Convert float to interger
Hi,
Stupid question but I can't find the anwser. Where is the function that allows meto convert a float number to a string?
Thank you.
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trasferire immagini da acquisiti da un camera da un while loop ad un altro
Moved to Italian board
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Labview put the acquisition and processing in different while loops that exchange data
Hello,
In fact, I have a vi that works on labview which consists of acquiring data thanks to a register placed on the big while loop and in the same loop, data is also processed(spectrum, display..). Now I have to separate both (acquisition and processing). I would like to put each one in a while loop and link them by the flow of data that I acquired. The problem is that the second one does need the data from the first while loop to be lunched. I had the idea to add flat sequence or even a cadenced loop but the problems are still not solved. So to sum up, the main problem is that the acquisition should stay in the while loop and the data should be transmitted to the second which retrieve it from lunching. The idea of putting the all in a flat sequence with two steps and put it in a while loop is to be banned because I need to keep.the acquisition in a whil loop.
Can you please give your suggestions. Its too urgent. Thank you.
Yasmine
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NXG Style Tab Control
I've noticed a weird issue with the NXG Style Tab Control and wanted to see if anyone else has run into this (using LabVIEW 2018). I have multiple tabs that I programmatically set visibility using the PageVisible property. What I noticed is that during runtime, if I hide tabs, the front panel still shows part of the outline (see vertical lines below). When I replace the NXG Style Tab Control with a System Tab Control, the issue disappears. Not sure if this is a bug or not, but anyone else see this behavior?
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What do you do when you want to store text in a single "cell" of a spreadsheet file?
This is not too deep of a programming question, I just wanted to hear what people do if you want to store a string in a single cell of a spreadsheet but it contains characters that would cause it to span multiple cells (at least in Excel). It seems like end of line, carriage return, and line feed cause Excel to shift to next row, and tab causes Excel to shift to next column (when used as the delimiter). My current idea is to replace with something similar, so I could reconstruct the original string if necessary. For instance "\t" becomes " -t ".
It will probably depend on the application and what kind of data you need to parse out later, but I just wanted to see what other people do!
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Keep Excel opened even though VI is running
Hello,
I'm making some code for Excel manipulations based on Report Generation Toolkit. But whenever I run VI Excel application is always closed. Tried to find where can I set the option but couldn't.
Could you tell me how to keep Excel open when run the VI?
Thanks in advance.
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LV2017 Application builder issue
Hello
I have updated a test application for a device we are producing from LV2013 to LV2017. Now I have trouble, to generate the EXE-file.
The test application contains a packed library, that does the communication over Ethernet with our device with help of a UDP connection. All is working fine in the LV2017 development environment, I could operate all functions of our device with the help of the test VI. Then I generated an exe-file with help of the application builder, and the application does not work. It shows the corrupted arrow, like a VI that does not work. I got also the notice, that a VI is not working, and I need the LV development system to eliminate the error.
Inside the development environment all VI's show no errors, I tried to play with the settings inside the application builder - always the same result, a non operating exe-file.
I also tried it out with LV2018 - same result. The exe-file does not work. I did also a mass compile of all the VI's before the build with no errors.
Does somebody have any idea, where I can start to look what is faulty here? Curently I can operate the
Operating system is Windows 7.
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Xilinx IPCores losing configuration: Absolute path problem?
We are using LabVIEW FPGA 2015.
We utilise quite a few Xilinx IPCores (Multiply adder and so on) but I keep running into problems. After committing changes (and checking out to a different directory on disk), I am often met with the IPCores claiming that their configuration has changed since they were last loaded and when I enter the wizard, the settings are back to default..... The xco files and such are there, I can verify this. Is it a problem that we don't commit the sim folder? Could this be part of the problem?
Does anyone else have experience with this?
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Unbundled class value different to actual class value
Hope someone can help with what looks like an obscure issue. I have a class called 'mcp2210', and one of the private data values is called "Handle". When I create the class, the "Handle" value is created and stored with the class. Everything looks fine up to this point. However, when I then try to access the "Handle" value, the unbundled value is different to the stored value. Putting probes on the class wire and the unbundled value, I can clearly see that the class wire holds the correct "Handle" value, but the unbundled value always reads as 256d.
Some other points of info:
1. Before I run this test VI, I can edit the block diagram. However, after I run the test VI just once, the cursor changes to the 'hand' symbol, and I can't edit it anymore.
2. On one occasion, for no obvious reason, the test VI ran fine, i.e. the unbundled value was correct. The it reverted back to the non-working state.
3. This code is part of a library which has been running fine for 12 months. However, I had to do a rebuild of the library to fix something else unrelated to this issue, and the fix got a bit complicated, requiring lots of mass compiles to get right. This issue has only surfaced in the new library.
4. LabVIEW version is 2016 32-bit.
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communicate with multiple SPI devices(ADXL355)
HI Labviewers:
I'm new to Labview,and now I'm using NI-8452 & ADXL355 to get the acceleration and Temperature data.
This VI is working properly.
Now,however,I need to communicate with multiple SPI devices(ADXL355) simultaneously.
I thought that I need to change CS line continuously ,but when I put two ADXL355 in parallel (as drawing)
I couldn't get the right data .
Could someone teach me how exactly should I do,thanks for your patiet.
(I know this VI is very Messy,sorry about that)
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Factoring of Integrers
I am trying to create a subvi to factor an interger and save all of its factors in an array. Im not too familiar with the math node but I tried using it to no avail, I can also solve this using pure labview as well but i can't figure out where to start on that end. Attached is a image of my math node code which doesnt run due to an error on line 2 apparently. Any suggestions??
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Controlling a fan with PWM and a counter using NI 9482
Hi all,
I am very new to labview and am currently attempting to control a fan using the Ni cDAQ-9178 chassis and a NI 9482 Module (electromechanical relay).
I am connecting the fan up to a separate power source and then have the one PWM connection connected to CH0a. When I run the program the module makes a clicking noise that changes frequency when I change the duty cycle which makes me believe the program is working, but I can not get the fan to turn on change speeds. (I know the fan works because I can bypass the PWM to get it to run at full power).
The fan should be running at 100 HZ and at a 15-90% duty cycle. One thing I also read is that there is an internal pull up resistor and that I should have an open collector output (I am not 100% sure what this means).
I feel like I am missing something simple here as to why I can not get this to work. Any help would be greatly appreciated.
Thanks,
Devin
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average collected data
Here is my project
It has 4 sensors, 2 displacement sensors, 1 temp, 1 proximity sensor.
The proximity sensor detects a steel plate (10cm long) on a moving table and counts a table passes (cycles) and gives a true signal for during table passes acquiring data, after passing I need the average data from the 2 displacement sensors during the 10cm.
Seems my example does not capture the right data. I use the collector but I am not sure if it collects only the proximity sensor is true.
Best
cpalka
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Stop/Start DAQ-mx acquisition with boolean
Hi Folks,
Newbie with a question here.
I have written an application to drive a simple actuator.
The actuator goes in and out as expected but I now need to measure the current needed to drive the unit.
As the actuator isn’t in constant operation I just want to acquire data when it’s being driven.
I’m using DAQ-MX but I’m struggling to stop and start the acquisition. The control program can generate a Boolean to start and stop things which seems logical but I need some advice on how to proceed.
P.S. Actuator travel time isn’t constant but it’s between 4 – 12 seconds
Thanks for you time
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Virtual Bench incorrect example code (for DC FGEN output)
Hi,
I am using the example code from here: http://www.ni.com/example/52072/en/ for a virtualbench 8012. It can generate arbitary waveforms just fine, however when I ask it for a DC signal it runs without error but without actually applying a DC signal to the FGEN output.
Has anyone else experienced this or have a solution?
Thanks
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Create and fill an array with IMAQ images for group averaging
Hello,
I have been struggling on a problem for a couple of days now, and I am looking for a bit of help on a "simple" aspect of NI LabVIEW and NI Vision.
First, I will just give the context of my problem : I have a camera (set on a microscope) which is grabbing images from my sample. I need to record the raw images directly obtained by the camera (so without any pre-processing) because I have some routines of post-processing to apply on them. However, while and in between recording, I need to move in my sample and either look for event or track them (manually). So I need in the same time to pre-process the signal and display it, so I can have a good visualization of the sample.
For this, I am required (by the different natures of the samples I usually work with) to switch between two types of pre-processing for visualization: (i) correction by the subtraction of a constant background image (taken in a blank part of the sample). This part is already done and working perfectly fine. (ii) correction by group averaging on N frames. And this is the part I have trouble with.
So the second type of correction is pretty simple in its description: (1) I collect N frames, (2) I average them (using the IMAQ Compute Average Image.vi so far), (3) and then I take the N+1th (raw) frame and divide it by the average computed just before. Then I restart from (1).
Using the examples and other topics ( for example here ), I have managed to make this running with a For Loop and a Ring acquisition.
The problem is that, until the foor loop is completed on the N frames, the program does not do anything else. Which means it does not display or record the raw frames anymore. So my frame rate becomes (true FPS) / N, which is terrible for my application.
I have tried several ways to do it, by adding pixels values of images and finally dividing them by N (with IMAQ Add.vi and so), but it does not work at all (I only got a black screen on display).
I feel like I could do this with a very simple way, by inserting directly the N IMAG Images in an array, processing it with the IMAQ Compute Average Image.vi on the Nth frame and re-initialising the array at the end. After all, IMAQ Compute Average Image.vi is designed to work with Image array (cf Online description). However, I cannot find anyway to create such array of images than by using a For loop (which is slowing my acquisition down drastically).
So how can one create an IMAQ image array without using a For loop (such as in the example given above)? Could it be done with a While loop and a shift register for example, so the display and acquistion of my raw images are not impacted by the group averaging?
Best
PS: I do not include a VI because I don't think it would be really relevant regarding my question, but I can send my test one if needed
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