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Tab Control: Chart data resets when changing in between tabs

March 17, 2020, 12:19 pm
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Hey!

 

I've been having some issues with a pair of waveform charts that I'm using as part of a front panel that'll act as an HMI for an application that I'm developing. 

 

As of right now, I have 8 different waveforms built as an array that is connected to a waveform chart (with t0 being the current timestamp of the program and dt being a 1000 ms constant) in one of the tabs:

AdrianDav_0-1584471532627.png

And in another one of the tabs I have a similar arrangement for a chart, except that I have 5 waveforms in it.

 

The thing is, with this arrangement, when there is a change of tabs, the history data of the waveform chart resets and I know that if I don't use waveforms and just bundle the data straight up into the chart, I could see all the plots separately and the data doesn't reset. But the thing is that with that approach, the X-Axis doesn't show the current date/time and I need to have that in the X-Axis.

 

I also know that with an XY Graph, things could be done in a simpler way, but I can't use a Graph because I'm working with properties of the plots of the chart in another part of the code. 

 

Do you guys know about any way that I could still use the arrangement from above and prevent the data reset that I'm experiencing?

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Condense multiple control arrays

March 17, 2020, 2:03 pm
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I want to add more to this but there isn't enough room. This is a small part of a larger program. What this section does is load settings from an excel sheet. The file has many sheets that fill the control arrays, turn buttons on or off per sequence, change voltage current and compliance of meters and switch relays. I am not at liberty to share the whole program. There is a similar save event. We can make changes in LabView and save them or make changes in a spreadsheet and load them. So how can I turn all of those references into an array which would make it easier to add more.

 

Capture.JPG

 

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LabVIEW for Linux Faster?

March 17, 2020, 3:18 pm
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Some of my staff is averse to using 64 bit installs of LabView or TestStand - there are always instrument issues that make them shy away from it. In the meantime, we are continually asked to make our tests faster. I feel that using 32 bit Windows and the RAM limitation will make LabView run slower (you can always optimize to some extent but there is a limit). If I were to use LabVIEW on Linux I would be in a 64 bit architecture. Should I expect some (even if it is minimal reduction in execution time?

 

I have seen TestStand improve over the years where it cleared the memory it used while executing (I am pretty sure anything before 2010 just gobbles up memory). Long executions would slow down as they ran as memory became less available. Does LabVIEW benefit from more bits and working memory?

 

I may see if I can drum up some test cases to see if I can do some benchmarks. However, my limitation at the moment is buying licenses to prove my theories... I can just do it all in python and free up money instead of memory... 

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Issue with Executable and .NET DLLs

March 17, 2020, 5:18 pm
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I have recently noticed different behaviors with LabVIEW and .NET DLLs whether I'm running a VI through a LabVIEW project or if the VI is converted into an executable. In my setup, I have a PPL that contains VIs that use different functions from the DLLs.

 

  • When I have a top level VI inside of a LabVIEW project, everything seems to work as I expect it to. The VI dynamically loads the PPL and is able to successfully make VI calls that are contained in the PPL. All the assemblies are used from the location that I've installed them at.
  • When I convert the same top level VI into an executable, things do not behave the same way as the LabVIEW project example. When I run the executable and I load the PPL, I notice that each .NET DLL is copied over to its own individual AppData folder. When I try to make the same call as in the LabVIEW project example, I get an assembly can't be found error. This is because the DLLs that I reference from my PPL have dependencies on other DLLs and relative directory locations are broken when the DLLs are copied over to individual AppData folders.

 I know one way to resolve this issue is to place the executable inside of the folder that contains the .NET DLLs, but there are 1000+ files in that folder so I'm hoping there's a way to avoid that. Is there anything that I can do to make the executable example behave the same way as the project example?

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March 17, 2020, 5:40 pm
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留学特殊申请（UI文凭毕业证‘雅思’（+Q微）2248162005速办伊利诺伊大学学历证书#UI毕业证书#UI假文凭#UI学位证书/UI文凭丢失补办,学历学位认证使馆认证留信网认证University of Illinois

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March 17, 2020, 5:40 pm
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美国Brandeis假学位+扣微：1151714174#Brandeis假学历#Brandeis假毕业证#布兰迪斯大学假学位Brandeis University

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MAX test panels

March 11, 2020, 9:36 am
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Is there a way to load a full function version of NI MAX (must have test panels) without LabVIEW? Or what is the minimum LabVIEW components necessary to have NI MAX with test panels.
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Generate an array from a boolean indicator

March 17, 2020, 6:10 pm
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Hello, 

 

I have a boolean indicator in my program which changes turns on and off every time a task is successful and unsuccessful respectively. I want to create a boolean array from this indicator such that every time the indicator changes value, it is recorded in the array. Can this be done? Could anybody please suggest a way to do this?

Thank you. 

 

 

 

 

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Serial Number

March 17, 2020, 10:59 pm
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Hello there,

I want to activate LabVIEW 2019 software but I can't find the serial number.

can you please tell me where I can find it.

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PCIe 7821R not being found by LabVIEW

March 17, 2020, 11:31 pm
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Hi all,

 

I have installed LabVIEW 2019 (non SP1) version and have installed the FPGA module.  Also, installed the Multi R devices and drivers.  Lastly installed the CompactRIO drivers and devices.  In NI-MAX, I can see the card.  In Device Manager, I can see the card and the FPGA.  Why wont LabView allow me add the FPGA as a Target in the project?

 

I create a blank project, right click on "My Computer", select New->Targets and Devices.  I get the prompt to search for attached devices, but nothing is populated. If I try to add an FPGA manually, LabViews says that I can not.  

 

Anyone else seen this problem?

 

Thank you in advance for any hints!

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Please help me convert LV4.0.2 to LV14.0.1

March 18, 2020, 12:41 am
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FESTO CMMT driver DC mode issue with Crio 9039

March 18, 2020, 1:06 am
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we use crio9039 as ethercat master to control FESTO CMMT driver, we can only process into freerun mode, can not change into DC mode. Can you help us about it?

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Two different sampling rates

March 18, 2020, 1:38 am
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Hi guys, 

i am using cDAQ 9189 and want to measure voltage and current (to calculate the electric work) on different electric motors. I made a VI using NI 9225 and NI 9227 and it seems to be working (VI_01.vi). But i need to add motors and don't have another NI 9225. So i am forced to use NI 9219, which only can do 50 S/s. 

So I am going to have two different rates for voltage and current (1613 Hz and 50 Hz), but i need have the same amout of samples synchronised in time. 
Question: What can I do? My idea is to divide 1613 with 32 and build an average of those 32 samples and build an average, but is this physically correct? I am not sure... 
Or is there any elegant solution how to do that? 

Thank you very much for your help! 
Jani 

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(Hex 0x4A) Memory or data structure corrupt. Class could not be loaded.

March 18, 2020, 2:50 am
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Hello!

I have a problem with my LabVIEW code...

The code was running normally, until I tried open it on the next day.

If i klick on the class -> load -> LabVIEW: (Hex 0x4A) Memory or data structure corrupt. The file "... .lvclass "could not be loaded.

 

The only difference between the working and the not working code was:

some new VI's and TypeDefs - no changes in the class.

 

 Another strange thing:

in the dependecies is the control of the class - is this normal?

 

Maybe somebody is known with this kind of error and might have some ideas.

 

Greetings!

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XNET Read Waveform Issue

March 18, 2020, 3:30 am
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Hi, I have a problem reading CAN signals after power down the bus participant. I configured the XNET as "Signal In Waveform" with a resampling rate of 50kHz. The participant is switched off and I receive the standard signal value (defined in the database). After switching the power supply on I receive the correct value, BUT after switching the power supply off again I still receive the last value - not the default value. Does somebody has an idea?

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LabVIEW restarting COM port?

March 18, 2020, 4:00 am
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Hi guys.

 

I have app on ATmega and when comes request from Labview app, ATmega starts sending data throught UART/USB (FTDI chip).

So i use VISA in Labview:

Yaamamoto_0-1584528726494.png

 

I notice when i run labview app its always reboot my ATmega. Its the same if i just disconect and conect USB to ATmega .

If i run Labview continously i can read data one more time and then is mega rebooted.

 

Its HW or SW fault?

 

If i use HyperSerialPort app i can smothly send comand to ATmega and then see comming data.

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LabView 2018 and 2019 crash when "Select .NET class" is clicked

March 18, 2020, 5:14 am
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I have a .NET dll which I am calling from LabView. This has been all working fine for long time now. But when I want to change the class of a .NET reference, LabView crashes immediately:

 

bna08_0-1584533346598.png

 

bna08_1-1584533584013.png

 

This happens in both LabView 2018 and 2019.

 

Any idea how I could work around this? It makes it impossible for me to complete the task I have been working on.

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calibration DAQ assistant

March 18, 2020, 6:10 am
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I'm trying to calibrate a LBS200 Futek load cell using the DAQ assistantin LabView 2016. However, once selected Acquire Signals-> Analog Input->Voltage  and selected the connected channel (ai0), the DAQ assistant display only settings and not calibration. How do I solve this?

 

 

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Synchronizing FPGA FIFO samples and XNET CAN signal

March 18, 2020, 6:56 am
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Hi,

 

Sorry for double posting, but I can't find an option to switch the categories...

 

I have a cRIO 9047 with AI modules (e.g. NI 9229) and a CAN module (NI 9862). The AI samples (one signal!) will be acquired within a FPGA-VI (2kHz) and buffered in a FIFO. Within a RealTime-VI the FIFO will be read out (100Hz) and stored in a RealTime-Variable.

 

In another RealTime-VI the CAN signal (one signal!) will be read out with NI-XNET Signal In Single-point (~100Hz) and stored in another RealTime-Variable.

 

On my host computer I would like to plot the data in one graph. How can I synchronize the AI and CAN data? The variable with AI samples contains a timestamp and an array with many samples due to the slower FIFO read out rate. The variable with CAN signal contains a timestamp and one single value. The timestamps should be synchronized(?!), but how to plot the different datalengths? Or is there a better way in general?

 

Thanks for replies!

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LabView class is loaded in multiple application instances

March 18, 2020, 7:16 am
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I have a PC labview project. I added a new class, then set the inheritance to be a child class. The class icon shows it is locked. The "Why is the library locked" shows "This Labview class is loaded in multiple application instances."

 

The project build spec does create 2 different applications. However the class that I added is part of only 1 app, none of its VIs are contained in the other app. The code seems to run ok. Is this an issue with locked icon? Any idea how to unlock it?

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