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How to trigger analog signal with digital signal using digital edge

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Hi,

I am having trouble wiring my digital trigger to the analog output. I am attaching a portion of the labview program I am modifying...in short, trying to get Dev1/ctr2 to control Dev1/ao1. The top portion does not make sense nor work, but it is my attempt to incorporate the digital edge module.

 

Thank you.

 

Edit - the analog waveform I am triggering is being read from a data file (table) that I've created outside the program. Ultimately, I want a 1 second square pulse wave (digital) aligned with a 3 second custom waveform (analog).


Match Pattern to extract word from text file

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Hi all, I want tried to extract specific word from a text file. For example, I would like to extract "the word" between "<STRING> the word </STRING>". But instead of getting "the word" between them, I get words after </STRING> also. Can anyone help to have a look on my code. Thanks a lot.

 

Best way to retrieve mask info from picture? (also Doom)

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I recently came across this very cool Doom WAD file viewer in the code exchange. It uses IMAQ functions for all its image handling, so requires NI Vision to be installed. I wanted a more pure LabVIEW version, so set about replacing all the IMAQ functions with LabVIEW's picture functions.

 

Pictures are created using Draw Unflattened Pixmap.vi in 8-bit mode from a combination of image data, mask data, and a 256-color palette from the WAD file. The replacement code works and, after adding a little programmatically generated fire, the mask provides a nice 'demon floating over a pit of flames' aesthetic:

labwad.gif

 

The viewer also allows for saving an image as a PNG. I wanted to use the picture mask as the alpha channel for the PNG, and found Darin.K's Mask to PNG Alpha VIs. These work with pixmaps, so the picture (with mask) is converted using Picture to Pixmap.vi. The problem is this VI doesn't extract the mask info from the picture, and a look inside that VI shows a DLL call (PictToPix) doing the conversion, and an empty array constant wired to the pixmap's mask element. So the mask info is lost at this point.

 

If during the pixmap conversion the background is set to a unique color not in the original picture palette, a new mask can be created from the pixmap based on that color using Create Mask.vi. This works and is the method currently implemented, but it feels a bit hacky.

Save Picture To PNG.png

 

Does a VI or DLL function exist for extracting the mask information directly from a picture?

Can messages

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Hi,

I am doing CAN messages testing using NI 9853 card and PCAN device.

when I am transmitting CAN message with ID 0B9BE601H through PCAN VIEW, i am reading 2B9BE601H CAN ID in labview. Can anyone help with this issue?

 

Detecting pills

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Hi

I want to detect broken pills, How can i do that ?Bad Image 2.png

Weibull (shape to life fit), Acoustic Emission

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Hi,

 

I am using acoustic sensor (up to 1MHz) type (8152C), which is connected to the acoustic coupler (5125C), and detected by NI 9223 with the cDAQ chassis.

The acoustic sensor will be placed above ball bearings rotating at different speeds from the inner race (ex.1800 rpm).

I produced  LabVIEW loops to detect and control the acoustic emission but still missing the final processing, after researches i found out that the following 2 is the best for my case.

1)Spectral analysis, analysing acoustical signal into its component frequencies (helps in the defect type).

 

2)Shape To Life theory, where a weibull distribution is fitted to it and the weibull parameters shape , and life can be estimated.

 

It is my first time to use LabVIEW for this project, could I place these 2 types in my LabVIEW VI? are these the best options for my case?

I was planning to capture 5 seconds worth of data for each bearing.

Thanks,

Yasser

Crash of NI Device Manager

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Dear community, 

 

when trying to start the NI Distributed System Manager (LabView Version 2019 SP1), I get an immediate crash message (see attachment). Does anybody know what this means and how to solve it?

 

Thanks in advance

Best 

Format into string converts some whole numbers wrong

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Hi,

 

I stumbled into this issue while trying to write some values to file, which had very small variations centered around 1. I decided to write all my values formatted as %#.16f (hide trailing zeroes, 16 digits of precision). Here is a sample snippet:

Format into string.png

 

 

 

 

Later I found that some whole values were written wrong to file. I noticed then that some ranges of whole numbers get converted to non-whole numbers, written as *.9 periodic. For example, 78 is converted to 77.9999999999999999.

 

The same happens within these ranges:

  • 78 to 99
  • 529 to 999
  • 4225 to 9999
  • 36045 to 99999
  • 298302 to 999999

Reducing the precision, say from 16 to 15, solves the conversion issue for the range from 78 to 99. Decreasing further from 15 to 14, solves the conversion issue for the range between 529 to 999, in addition to 79 to 99. So on, and so forth. This limits the highest number of digits of precision to 11.

 

This happens on LabVIEW 2017 and 2019, 32-bit versions. I am wondering is others have seen this and/or if there is a bug already reported about it.

 

Best regards,

Sergio


comma delimited spreadsheet string into string array

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I have comma delimited spreadsheet string like xxx,yyy,zzz. i want this spreadsheet string into string array like xxx yyy zzz Is there any function available in palette? I will be grateful if anyone give me the solution soon.

Output

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Hi all!

I have one 1D array of string and two 1D arrays of doublee. 

I need to export it in excel or in a txt file.

in the first column i want the array of string and the two arrays of double in the adjacent columns.

Using Ocean Optics spectrometers in LabVIEW NXG

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Hi all,

 

I am struggling to get my Ocean Optics USB2000 and Maya2000 Pro functioning in LabVIEW NXG. The Maya2000 Pro works fine in LabView 2019 and the USB2000 never seems to install correctly regardless of what driver I use.

 

In System Designer I can see the Maya2000 Pro and under errors and warnings it states 'Driver not installed', and in the item panel it states:

 

'NI-VISA support for LabVIEW NXG 4.0

Version 19.5.0

 

NI-VISA

Version 19.5.0

 

Instrument driver not found'

 

I installed the drivers found my searching in NI Package Manager. Any assistance on getting either of these spectrometers to work would be much appreciated!

PXI 8431/16 Read Discrete

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Is there any way for the 8431/16 to just read discrete high/lows and not in 485/serial format?

 

I want to run data from the 6515 and 6528 to be read by the 8431/16.

Plot a 2d string array from csv file

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Hallo Everyone, 

 

I know there are similar Questions About my issue, but I tried everything there is and didn't get the final result.

I want to plot a csv file which is a 2d string Array but I've been running into string Format Problems. The data actually starts from the 16th row, and everything before that are just headers. I tried to convert it to a 2d double Array, but Nothing changed.

If anyone can help me figure out how I can Display my full data, and then plot it, I will be very grateful for ur help.

 

Thanks Peter

How to trigger data acquisition for a limited set of values using DAQ Assistant?

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I am trying to acquire data across 3 load cells and record the 3 curves from a waveform graph as well as record the peak values reached. The module I am using is NI 9237 and program is LabVIEW 2016. In researching how to do it, it seems like I need to set up a trigger to acquire data between the desired set of values and save the sample, but from what I can find it seems that NI 9237 is not capable of setting up a trigger by itself (the trigger options within DAQ Assistant are all greyed out). See the attached file and snapshot below. Any help with this would be greatly appreciated!

 

jpartain_0-1581439115375.png

IXXAT USB-to-CAN CAN open


RT Build and Deploy cRIO - Why Extra VI Compile

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Hi all,

 

We are developing a somewhat extensive embedded application that runs on a cRIO-9049

The project is constructed with

- multiple libraries (not packed )

- no shared variables

- no load from references

- many vis are inlined for performance

- VI have 'separate compile code' option

- the project as about 2000 VI

 

When I build the application with many of the compiler options but not

- remove type_def 

- not remove inline VI diagram

 At the end of the compiler process it saves all the VI... I guess with the optimized compile code.

 

The big mystery is when I come to ' Set as startup', there is an additional compilation of up to 100 VIs ad then the deployment loads in another large handful of VIs.

My questions are:

1. if I have just build an exe why is there more compilation at deployment

2. Why is there extra deployment of VI.  I would have thought that there ALL contained in the startuprt.exe 

3. If we have an extensive library structure in the BUILD config do I need to link the libraries in using the 'Always Include' options

 

thanks in advance

 

 

Can't get LabView to plot a csv file

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I'm a novice at using LabView, and coding in general. For an experiment I'm working with, a data report is generated that I've converted into a csv file with three columns of data. I'm trying to take the first two columns, time and photon counts, and plot them on an x-y plot. It seems like the graph function can't use the csv data directly, so I've tried splitting the first and second columns into separate 1D arrays and plugging those into the graph. But for some reason, only the first column is being read -- when I each array as a matrix to see if they were being read in correctly, the values for the column 1 array scanned in and displayed fine, but the matrix for the column 2 array came out blank. I've enclosed a screenshot of my block diagram. Can anyone tell what I'm doing wrong?

Simple way to delete your pof account ?

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Here are the methods referenced how to delete Pof Account:

1. On any program you like, scrutinize the Plenty Of Fish Home Page.

2. Enter the email/username and enter the mystery word related to the record. By then snap Mail Check.

3. Snap on the Help tab at the upper right of the page just before the "Logout" elective.

4. Under "How might I delete POF account," click "Eradicate account" heading from various choices.

5. You will by and by go to your record's crossing out page. To deactivate POF Account, just snap on this quick association, you can go direct to this page. You conceivably need to enter your username and mystery state if you press this relationship without marking in, by then you will land at the dropping page of your record.

6. You are by and by drew closer to enter various information, for instance, your username, mystery key, inspirations to leave your POF account, what number of dates you have been managing, and whether you will propose POF to others.

7. Other than this zone, you will in like manner be admonished that if you eradicate POF account, you won't have the choice to continually use any data related to your profile.

8. In the wake of embeddings all the data, click the "Quit/Give Up/Delete Account" tab.

9. So now you've found a perfect partner for yourself or you've done web dating things or you've continually dated a wrong one and finished the single one! Or then again you may be discontent with the eventual outcomes of your bounteous fish account.

10. There may be an inspiration driving why on Plenty Of Fish you never again need your profile and you have to acknowledge how to delete plenty of fish account.

Need a trigger based on particular angular position of encoder

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I am completely new to labview and concurrently doing tutorials to understand the layout better. For now I have a quad encoder that I have configured using a simple DAQMX which gives me the position in degrees based on the position. Now I want to send a trigger to an external camera when the encoder is at 30 degrees. How do I go about this?

Need help running programmable power supply with LabVIEW

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My task is to run a programmable power supply (Circuit Specialists PPS 2116A 32V/5A/160W) with LabVIEW so I can choose the current. Currently, I have installed the driver and I used that to build the program (screenshots attached below). I have also included the program. I keep receiving this error: Error: -1073807339, VISA Read in Circuit Specialists.lvlib:Initialize.vi->CircuitSpecialistsDriver.vi 

 

Eventually this program is suppose to be able to take in multiple current values that can run for a given amount of time, so both the time and the current are suppose to be user inputs. Before I was using the Instrument Assistant but I couldn't figure out how to do multiple runs or do it for a specific amount of time with this so I stopped. 

 

I am new to LabVIEW I don't know what this means. I will take any help I can get because I am really struggling with LabVIEW. Thank you.

 

 

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