I have labview 2016b connect to two GPIB devices, an Ethernet instrument, and two serial port devices. These are all done through USB ports and a USB Hub. Also the PC has no Ethernet port and has a USB to Ethernet connection. These devices are read and the data collected is put into an array. The time period between reads is 5 seconds. My program may run several hours but eventually it will freeze. The last time I checked it it was stalled on a vi that was trying to read a GPIB device. There's no loop in this vi. It should pass right through. I had to stop Labview and restart the PC. Could it be that I'm swamping my program with all these devices.
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Labview 2016 Freeze
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Array to Spreadsheet String - no end of line
In the attached VI, I was expecting to get an end of line character at the end of each array element. In the string indicator on the front panel, I get one row instead of three. What have I done wrong?
Thanks.
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multidevice task not supported (DAQmx)
Is there any documentation or specific hardware list of devices that cause:
Error -201426 occurred at StartDAQmx Start Task.vi:7220003
Possible reason(s):
One or more devices do not support multidevice tasks.
Some reasons are obvious (separate chassis...) but I was surprised wnen I added a second PXI-6529 board for digital input to one of my PXIe chassis, and now have to revise the software to add another task. Two 6529s can't be in the same task. I've looked through the board manuals and the NI site but can't find any documentation on why, or what else I might need to watch out for in future expansion with other PXI boards.
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Building LLB failure due to Error Copying File - Discrete Math.mnu
I am trying to build an .llb file using LabVIEW 2014 64 bit version. This error just popped up for me today, and I don't quite understand it. I never modified this file, and when I browse to it everything seems acceptable.
Does anyone have any ideas how I can eliminate this error, or what causes it?
Error copying files.
Source: C:\Program Files\National Instruments\LabVIEW 2014\menus\Categories\Mathematics\_elementary\Discrete Math.mnu
Destination: C:\xx\library.llb\Discrete Math.mnu
Click the link below to visit the Application Builder support page. Use the following information as a reference:
Error 1 occurred at AB_Dest_LLB.lvclass:Copy_File.vi -> AB_Source.lvclass:Copy_SourceItem.vi
Possible reason(s):
LabVIEW: An input parameter is invalid. For example if the input is a path, the path might contain a character not allowed by the OS such as ? or @.
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NI-488: Command requires GPIB Controller to be Controller-In-Charge.
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Test performance Labview project on myRio
Hi everyone,
can i simulate the hardware of the myRio board on my pc to test the performance of my Labview project?
I'm developing a new project but i can't load it on the board because it is used for another one.
Thanks!
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How do I move my block diagram code into sequence structures without breaking all the lines?
How do I move my block diagram code into sequence structures without breaking all the lines? I have a small bit of code that needs to be execute at the very end of a loop, but if I try to move the contents of my loop into a sequence structure all the lines break... and I would rather not have to rewire EVERYTHING again.
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High School Test Stand for Hybrid Rockets, labview and sensors integration
Hello everyone, I am representing a high school rocketry program which is in the process of redesigning and updating our test stand. We run the test stand to validate specific fuel/oxidizer/nozzle combinations before flight of our 100k ft class rockets. Unfortunately, the teststand labview programs were designed years ago by students who neglected to pass on their knowledge, and then edited last year by a class with minimal training. During their edits, they broke the labview program. Therefore, this year we are starting over at either a blank slate, or a former stable version. Unfortunately (again) upon exit last year, the test stand wiring was unplugged. Therefore, it is currently inoperable. We are in need of help to determine how to reassemble the sensor/solenoids, and on tips for refining the labview program in use. This class has so far studied the Labview Core Module 1, and is willing to progress. Attatched is the currently in use program.
Hardware in use
3 Omega Pressure Transducer to measure chamber pressure during combustion (PX309-2KGV)
1 Omega Pressure Transducer to measure Head Pressure (PX309-1KGV)
1 Load Cell to measure thrust (details forthcoming)
1 "MOOG" valve (details forthcoming)
1+solenoids for N2, C02, 02, N20
1Load cell to measure tank fill (details forthcoming)
Possible other sensors, to be determined tomorrow.
Connected to a cDAQ-9174, with modules 2 x 9125, and 2 x 9481
So far all labview code has been edited in labview 2013 on a single sony laptop that is used for the teststand.
Due to school schedules, replies may be delayed somewhat, we will strive to reply as promptly as possible to this thread, more info will be added tomorrow when we have acces to the teststand once more. Thank you for any help, and for your time.
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Torsional Vibration Analysis (TVA) - NI Hardware/Software
I have an application were I need to perform a TVA on an engine using two encoders. One of the encoders is coming in at 720 pulses/rev (360 tooth disk with sync signal) and the other is coming in at 40 pulses per rev (20 tooth disk with 2 missing teeth). The maximum speed of the engine is 10,000 rpm. Based on my calculations this puts the required sample frequency at over 120kHz. The pulses are TTL level.
I am trying to find out if anyone has any recommendations for this application as far as NI hardware and software tools. Also would like to hear if you have performed this type of analysis before using NI hardware/software.
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Parsing out channel properties of IO Variables
I've got a situation in which I would like to configure the Daq on a cRIO from a configuration interface on a Windows host. In particular, I would like to get IO Variable addresses for all the Scan Engine channels configured on the cRIO. The configuration program runs on the Windows host and cannot deploy any deamon to the RT that could query the hardware. It needs to run as if the cRIO is not present.
The configuration program is part of the same project as the cRIO, so my thought was to parse the project to find the relevant items. Here's a post that does something very similar:
https://decibel.ni.com/content/docs/DOC-16630
However, this has several problems. This example was written in 2011. I'm using 2015. Apparently the properties changed since then. The "Find Children" (which is no longer named "Children []") does not give me the chassis reference on my 9068. Instead, I was able to use the "Owned Items []" property, which gives a bunch of things, and then I search the TypeString of those things until I find one that is "Chassis". Fair enough. Then the Chassis ref gives me the Modules, and the Modules give me the channels. Sounds pretty good. But all I get are the channel names. I can't seem to find any properties that define the module type or the IO direction. E.g. I would like to know if a variable is Boolean or Real, and if it is an input or output channel. You can deduce that from "standard" names, if the project hasn't been edited to give them creative or meaningful names. But it seems like there should be a way to find these properties directly.
Any ideas?
TIA,
DaveT
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Picolog-HRDL.vi (ADC20/24): How to deal with collecting data from several channels?
Hey, I am writing a program in LabVIEW 15, and as part of that I need to measure pressure using the Picolog ADC20/24. The example vi provided by picolog (see attachment below, driver 64-bit LabVIEW : https://www.picotech.com/downloads/_lightbox/pico-software-development-kit-64bit and driver 32-bit LabVIEW : https://www.picotech.com/downloads/_lightbox/pico-software-development-kit-32-bit) seems to do most of the work. What I dont understand is the "channel enabled?"-property. On the front panel, they placed 16 switches, one for each of the 16 channels. From this I assumed that when I only want to record, say, channel 2,7, and 14, I can turn off the other channels. The code in the vi, however, does not seem to do this. It looks like it runs through all 16 channels, regardless of them being turned on or not? Could someone shed some light onto this? Thanks in advance!
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How to use Labview to control motorized stage??
Hi,
I'm new to Labview and doing a project which requires using labview to control motorized stage(XYZ axis). I need to use Labview programming and have no clue at all. Looking for help, Thanks a lot!!
Lei,
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Editing the Physical Channel CDAQ
Is there possibility to change the Physical channel names(a0,a1...a16) of DAQmx device.?
for example Dev1/a0 to..Dev1/10001
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General Labview Programming
Hi Programmer,
I am new to Labview.
I received a "large" program for study purpose.
Large in terms of UI(3x1080pix to fit) and program size (main.vi 2MB in size).
It makes it difficult to read and study, example, selecting "Case" and "Stacked Sequence Structure", need few seconds to load. Any object or line move from diagram screen will need time to refresh.
Saving the program even longer. I am using a 32bit / 4 core I5 Laptop.
My question.
The "Slow" is it due to Large Diagram?
or Huge main.vi program?
Will creating more sub VI can solve the "Slow" issue?
Will placing the tools closer, smaller diagram will help?
Thanks,
Newbie ..
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Disable single stepping
Maybe a stupid question. But in Labview when I tried to run the program stops at a block (unbundle) which starts blinking. Then I can press 'Step over unbundle' and the program goes to next block. I just want to run the program without stops. It is not a breakpoint there (breakpoint manager empty). So how can I disable the automatic single stepping?
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What is the output of the SENT Driver API
I'm reading the SENT output of a vehicle accelerator pedal on an oscilloscope and with embedded windows 7, LabVIEW, and a cDAQ 9132 and 9205 analog input module. I don't have a FPGA system at this time. When utilizing the "SENT Driver API - National Instruments", what is the output value? Is it a hex value, binary, decimal, array of values? How does the SENT Drive API know how to interpret the serial data from the accelerator pedal, how does it determine the specifications of the signal output from accelerator pedal.
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cRIO, Webservice (RESTful) and Frontpanel
Hi there,
I created some simple webservice VIs for a larger application running on a cRIO. The webservice VIs can be used to send simple commands to the application and give feedback. So far I used a LV frontpanel for interaction with the system, but for several reasons I am looking for an alternative way to do this.
This worked fine in the development environment. After deploying the webservice VIs they communicated with the application as required and I am able to control the system using simple URLs typed in the browser address bar. Later on I will add static content, but for debugging this is fine.
The thing is that now I compiled and deployed the application, and now when I try to open the front panel I get this error message:
"Requested VI is broken and cannot be viewed or controlled."
Previously I did not use the NI-Application Web Server, so I installed it in order to be able to use web services. Are there any conflicts between Application Web Server and Remote Panel Server? Any suggestions on how to proceed?
I am using LV 2012 and NI RIO 12.0
Best regards,
Simo
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How to sort out the rows from the the table which belongs to the same name and save to the .txt file ??
Hello,
I am facing one problem, that I am reading the .txt file which has several rows and columns.
Third column represent the group name, like group 1, group2 and group 3. .txt file attached in the attachment.
I wanted to generate the group wise .txt file, like all raws which has 3rd element name group 1 should be in one .txt file and all the rows which has 3rd element name group 2 should be in one .txt file.
I hope I have explained my problem well.
pelase guide me how can I have solution for this problem.
Thank you very much in advance.
Regards,
Ankit.
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How to use a Timer and an Event case with LIFA/Arduino
Hi everyone,
I feel like my question will sound really stupid, but I cannot find the solution. I want to use my arduino to do two task at the same time. I want to use a while loop with a timer, to read my pins in my arduino. That is really easy. But then, I want to use also an event case to do different type of things. In the example I downloaded, I simply use an event to activate my fan. Once again, I have no problem to use this by itself. But I cannot find a way to use the both at the same time, especially when I want to exit my app. Because I use my arduino inside of my event case, I put it in another while loop. But, I also want another while loop, but which uses the timer. In my example, if you use the Highlight Execution tool, you clearly see that my signal goes to the while loop that contains the event case, but not the other one I want to use as a timer. It's probably because I miss something about the architecture, it's just to give you an idea. I simply want to know what is the smartest way to combine my event case and my while loop using the timer, and how to close them correctly. I'm not really a Labview expert, so it's kinda difficult for me. If what I say sounds obscure, I'll answer all your question without any problem.
Thank you so much for your help, and your attention.
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Change plot color between cursors?
I have been trying to figure this out, but to no avail. Here is what I would like to do:
I use the cursors on an XY plot to read out the information only between the cursors for further data processing (done with property nodes and a basic sub-VI I wrote to print the array of points between the cursors). This works great. What I would like to do (i.e. my boss 
) is to have the color of the line between the cursors change to a different color than the rest of the data trace. I tried a few property node things but nothing worked. Anyone have a suggestion (if this is even possible)? Thanks in advance.
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Test Rig Questions
So i have a new project coming up shortly. We currently have multiple test rigs that are driven by labview on different sites within our company. Each test rig has individual programs created for the part it has to test. Each part is virtually the same.
The plan is to replace this with a generic programme that loads variables from a database dependent on the part number selected.
The equipment will be the same on all test rigs. I know there is a few issues to sort out with networking across multiple sites but the plan is to create the generic test program and have a database with all the input variables stored on the network server. Whent the program is excuted it just pulls the variables required fromt the database.
This means when a software update is made its just gets rolled out to each site seemlessly. I am thinking of using an excel database with each row being a different part number and each colum being a different variable.
Then when the program is finished the results will get saved to another database with the results. As the database is stored on the company server anyone can then go and find the results for any part tested at any of the sites when ever.
I know the decription above is quite vague but im just looking for guidance to see if this is the best way to go about it, Is excel the right tool to use as the database? Is labview the correct software platform to use rather than NI Teststand etc?
The instruments connected to these rigs all have labview drivers and are off the shelf equipment such as keithly voltmeters, oscilliscopes etc.
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