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How do you read in and work with I24 binary data into LabView?

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Hi there,

 

I have a program that is reading binary data in as 16 bits per sample.  I have some binary input files that were saved as 24 bits per sample.  How do I convert my old program to handle this data.  I realize that LabView doesn't have built in I24 conversion - how do I do this myself? I found a post that referred to using a boolean array to create your own 24 bit number - but I don't understand what that means...  Any help would be appreciated!

 

Thanks so much!

 

 


XY Graph plot to infinity hiding other plots

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Hello,

 

I use an XY Graph to draw some limits. These limits are given by the plot 0 and plot 2 which is why I have them set to "Fill to positive and negative Infinity" respectively.

Problem is, I now have another plot (plot 3) to display which doesnt fall within the specified "limits" drawn by plot 0 and 2. The result? Plot 3 is being covered almost entirely by the other plots with the "fill to.." option.

 

TL;DR: Is there a way to make the plot 3 display over its entire length without being covered by the fill to x infinity plots?

 

Current result:

XY Graph Plot to Infinity.png

 

Desired result:

 

XY Graph Plot to Infinity (desired).png

how do start with button myrio

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Hi everyone, who can help me to know how can i starting and ending my VI with the button of myrio 1900 and thank you.

PXI-2514 triggering with TTL signal

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Hello,

 

I'm looking for help regarding opening and closing of the individual relay on PXI-2514 card through use of TTL signal.

I'll appreciate any help.

 

And, as this is my first post - hello everyone, I'm glad to be here :smileyhappy:

cRIO output large waveform

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Hello,

 

I have cRIO with DA converter and I need to output digitalized data. The problem is, it is too large to send the whole waveform to the fpga at once. So I am thinking about synchronizing it with the host and periodicaly send only parts. Does anyone have a better solution or advice about this matter?

 

Thanks 

only read boolean on change.

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Hi, i have a vi thats sends an emal when a LED light turns on. the led is controled by a bunch of other stuff. What im looking to do is only send 1 email when it turns red however the rest of the code must continue to run at all other times. I have 3 LEDs per indicator and about 12 indicators and if more than one of them light up the red LED its going to start spamming emails the way i have it set up now.

 

So to put it clearly i need to detect if a boolean has changes value and then see if that value = true and if both state change and value are true then send email.

Why isn’t active an event structure with a True/False Result Boolean?

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Hi 

Why bellow block diagram isn't work? and Boolean never is True?

 

Thanks.

 

DAQmx task data logging

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Hi,

 

 

Can someone pls kindly help me attached vi?

I have difficulty in datalogging part. I need to read 4 Channels Thermocouple k type sensor from NI9211

Need format of Datalogging in Date , Time and 4 Channels of Thermocouple (each column each channel). Every one min write to .tdms or .xls or .txt file. and Collect data log for 1 day in a file. Front pannel displaying Temp value read every 1 min.

Have some restriction to do my project due to I have to run the project in executable file and can not be used with DAQ assistant..

Can pls kindly help me with datalogging for every 24 Hrs log in a file.. Either in .tdms or .xls or .txt format..

 

Thank you very much,

 

Brian


Using actor framework 2014

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I've used earlier versions of the actor framework just fine. Then I installed LabVIEW 2014, and I do not know how the new framework is supposed to function. Is there some example of how nested actors are supposed to work? I've been looking around but actor examples are strangely absent.

 

Labview + neMESYS syringe pump

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Dear All,

 

I am a beginner in Labview. I understand that I have taken up a tough task in the initial run, but i hope to be helped by you all!!

Ok, let me brief my plan.

 

I have 4 syringe pump controls from NeMesys - Cetoni, which comes up with a neat GUI. But due to some constraints in our application, I feel that it would be better to control those 4 pumps through an independent LABVIEW program. But I have no clues where to start with.

 

1. Do I need any interface or handshake programs to be installed?

 

2. How do I differentiate one syringe pump with the other?

 

3. If am able to identify one of those syringe pumps, would i be able to replicate it for the rest?

 

 

Kindly suggest, all your help is appreciated!

 

 

Regards

Mich!!

Saved file size decreases with time

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Hi all, 

I am using Data acquisition system with  rate 10000 and 1000 sample per channel (exist 4 channels) to acquire analog voltage signals to measure the amplitude in each channel.

Moreover the raw signals are saved as TDM file of 1 minute. The system is running continuously for one week. I noticed that after 3 hours the saved file size is decreased as a function of time.

The size starts with 50 MB/min and after 3hours it became 42MB/min, after 1 day became 11MB/min. That indicated the data was lost , please, what is my programing mistake.

 

Thanks

User event for array of waveforms with attribute

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I have been transferring data in a Producer/Consumer architecture via User Events.  The data consisted of an array of waveforms. When I added an attribute to the waveforms the code breaks with two errors about Create User Event: User event data type is unnamed or has elements with no names or duplicate names, and Contains unwired or bad terminal.

 

From reading the help on user events it is not clear that arrays are even allowed: "user event data type is a cluster of elements or an individual element whose data type and label define the data type and name of the user event."

 

From experimentation it seems that arrays of numerics and arrays of wavefroms without attributes work. A single waveform with an attribute can also be used. But an array of the same waveform with attribute leads to a broken run arrow. It also appears that I can put the array of waveforms with attributes inside a cluster and then create the user event.

 

Is this a bug, an undocumented corner case, or some "feature" that I do not understand?

 

Searching for User Event for Array of Waveforms generates some interesting, but mostly irrelevant results.

 

Lynn

GENser library/VI

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I am very new to LabVIEW and this forum. So please let me know if I should post this question elsewhere. I inherited a bunch of LabVIEW programs from another guy and trying to understand how it works. I'm trying to open a LabVIEW VI with many sub VIs. From what I understand, there is a sub VI called GENser that is missing. When I try to load the VI, Labview keeps searching for GENser config, GENser initialize, GENser open, GENser close. As far as I could tell, this sub VI reads the voltage supply and passes it on. I tried to search for the VI on the computer and it did not show up. Are there any tips to figure out what this sub VI does? Is GENser a generic name for a type of VI?

 

P.S.: The guy who worked on this has moved on and no one else here knows LabVIEW!

 

Thanks

Asade

Why exactly can't I inline this?

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I know that property nodes and such prevent a VI from being inlineable ( or at least I understand why statically-linked property nodes prevent this.

 

I am writing to a FPGA DMA FIFO from my RT application and cannot inline the following piece of code.  (This is all that is in my VI apart from the object terminals themselves.  It's a static VI, not Dynamic Dispatch.

 

Notinlined.png

 

Why not exactly?  Is this just an over-zealous checker saying "Nope, no property nodes allowed" or is there something inherent in the call that prevents it being inlined?  I recall subroutine priority banning ann asynchronoud calls because it could not actually be interrupted.  Is this something similar?

 

I'm using LV 2012 SP1.

How do I inherit from a class defined under "vi.lib"?

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I've been developing a series of reusable LabVIEW packages for my company. Up until now, my strategy for reusing packages has been to convert them into packed libraries when complete and add those packed libraries (and any others it depends on) into a 'lib' folder within the root directory of other projects that would need to depend upon them.

Today I found out that I could use VIPM to distribute my packages a lot easier. I've managed to build and install VI packages for of my bottom-layer packages (the ones that don't depend on anything else). All the files related to those packages are now installed under my 'vi.lib' folder on my local machine. I'm now trying to update a project on the next bottom layer, which depends on two bottom-layer projects.

 

Call this project "Project C" and say it depends on Project A and Project B. Originally, I would have had something like the following:

.

└── lib
    └── ProjectA.lvlibp
    ├── ProjectB.lvlibp

├── src
    └── ...

In Project C, I define a class that inherits from a class within Project A. That works absolutely fine because when I go to Project C's class properties and its Inheritance tab, I can see and select the classes contained with the locally-kept lvlibp files.

Now that I've installed Project A and Project B as packages under "vi lib", it doesn't make sense to keep packed library versions of them under a local 'lib' folder. However, after having gotten rid of them, my class in Project C complains about inheriting from a missing class, and I don't see an option to point it towards the same class kept under "<<LabView>>/vi.lib/My Company/Project A".

How can I create VI packages that contain classes that extend upon classes defined in other VI packages that have been installed on my local machine? How can I refer to controls installed with packages in general, in addition to just VIs?


cdaq 9181 no supported devices found

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Hi, I´m new to Labview and I have a CDaq 9181 with a NI 9201 module in it. I see the device fine in measurement and automation explorer and it gives a good result on the self test but I can not find it by using either daq assistant or by using the measurement I/O. I need help with how I can find the unit in Labview for programming. I have not got any sensors connected to it just now but the device is connected through ethernet to my computer. 

 

Please help.

Axel Sig.

Using LabVIEW to simulatenously control 256 Outputs on FPGA

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Hello,

 

I am a first year graduate student classically thrown into learning LabVIEW, so I would much appreciate some help with the code I am trying to work out. To give you an idea I started watching the tutorials on creating loops in February. For reference I am on LabVIEW 2014 and using a CRio-9066 with 8 modules and 256 total digital outputs.

 

The goal of the code is to 1) generate on/off times for the state of the outputs on the FPGA VI and 2) to communicate this with the FPGA VI in real time. The reason the code is on a computer VI and not contained on the FPGA is because I need to use a normal distrbution function (which has inputs mean and standard deviation and outputs a value accordingly) to determine the timing. This is easily achieved on the computer, but not so easily achieved on the FPGA interface. It is essential that each output follows it's own unique timing function for my purposes.

 

The way the code works is that each output has it's own while loop containing a two-frame timed loop (see attached.) A sub-VI I made (with a sun icon, see attached) outputs a timing value each time it is called, and this value delays the next iteration and during this delay sets the value of the local variable as true or false (on or off.) The state of the local variable is continuously communicated with the FPGA VI using a read/write control elsewhere in the program. The FPGA VI itself is a very simple VI which has boolean switches attached to each desired output.

 

This code works very well for 128 outputs. However, when I try to use it for all 256 outputs it does not work. The VI does not report any errors, however about half of the loops are apparently not executing. My suspicion was that there is a limit to the number of processors that can be simultaneously utilized to execute loops in a VI, so I split the VI into two parts, each with 128 outputs communicating with the same FPGA VI. Again, I had the same issue. I am not sure if this is due to processor overuse or UI latency in labview (since the front panel is rather cumbersome.) Any suggestions would be greatly appreciated.

 

One thought I had to work around this is to create a VI which generates timing values and stores them in an array. Then I could create a simple VI on the FPGA which reads these values and assigns a true or false state to the output accordingly. However, when I pasted the array into the FPGA VI I was returned the following error: "The FPGA module does not support variable-sized array on the front panel of the top-level VI." Any suggestions for working around this would be greatly appreciated as well.

 

Any thoughts, comments or insight would be greatly appreciated. I am new to this so I realize my code is probably inefficient and such, so any tips would be awesome. Thank you.

how to add a control to a Tab

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Hello, thanks for reading my question.

I've been restling with this for several hours. I'm just trying to modify one of the samples provided in LV2014.

1st I can add a control, from the controls window, to a tab similar to the original controls as you can see from Ref[1], I added the extra and gate to AND Boolean Y & Z, tested it and it works fine. This seems to work on any tab, in other words I click the tab I want and select a control I want an it works fine.

2nd I want the control to actually look the same, refer to Ref [2]. I could not figure out how to copy and past the orignal control in the UI panel but was able to copy and paste the control in the block diagram. However, the control is not associated with the tab and is it should be a simple mater of draging on to the active tab but not!

 

Also is there some explaination as two why Boolean z, the one I dragged onto the tab looks different than Boolean Y in the block Diagram window? Is it because the Boolean Y was customized?

 

 

Adding control to tab.jpg

VI Package Manager

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Hi All,

 

I have been given the task of evaluating the VI Package Manager as a means of distributing code to other developers using our hardware. I was using an older 2010 free version and had some limited success & problems. SoI have upgraded to the 2014 version (build 1967) free edition. With the 2014 version came other issues. When I use the package builder to create a package it runs for awhile and then errors out with Error 7 occurred at NI_LVConfig.lvib:Load.vi  (see attached picture). I do have OpenG installed. I have also included pictures of the palletes and source file settings in the package builder.

 

Thanks much!

 

 

Installing an USB driver

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Hei,

 

My goal is to establish USB bulk communication between an USBdevice and Labview. I have been following this procedure: http://www.ni.com/tutorial/4478/en/ and used NI-VIsa Driver Wizard.

 

Everything went fine till I  have to create cat file. This I have to do  because my OS is 8 and in oder to get "allowance" to install the drivers I need to have it digitally signed. Appereantly it should be at location:

C:\Program Files (x86)\Windows Kits\8.0\bin\x86

But I can't  find the in2cat exe nowwhere. I reinstalled the the windows kit where the inf2cat appereatly is couple of times. So,

 

How do I get to inf2cat?

Is there any other "cosy "way to establish USB communication?

 

Any recommendations or advices are also appreciate.

 

thanks for the help

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