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Crashes when calling a Vi

June 13, 2018, 6:29 pm
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Hey guys,

 

I am very new to LabView, be aware. I have a VI (that i did not write) that, when I initially ran it, it worked just fine. I did not change it (to my knowledge) and now it crashes every time I run it. It just asks me to send an error report to NI (which I have done). I am having a hard time figuring out the problem because of course when the program crashes, I can't see what the issue is on the block diagram.

 

Does anybody know what could be the problem here? I can't find anything, but I'm new enough that I could easily miss plenty. Attached is the VI

 

Thanks for any and all help, it is much appreciated

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Probably a bad way to implement a timer...

June 13, 2018, 7:00 pm
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Hi all. I need to implement a timer application that manipulates controls on a VI based on a time protocol. We are controlling a stimulator, but it might as well be an LED for the sake of discussion. The time protocol consists of successive intervals, each of which has a duration and a mode. The mode is either "stim", "no stim" or "alternating".  Alternating intervals have a sub-interval duration. For example, a protocol might consist of a 2-minute "no stim" period, followed by a 30-second "stim" period, followed by a 1-minute interval during which stimulation is alternated on and off at 20-second sub-intervals.

 

We need to be able to pause the timer, and while paused, stimulation will be "off". 

 

My initial solution is attached - I found the pause handler in the forum. For simplicity, I am ignoring the alternating case at the moment. The "Stim on/off" indicator is a stand-in for the stimulation control button in the real application.

 

This appears to work, but I suspect a queued state machine might be a better solution. I can't figure out how to get started on that solution though. Any thoughts?

 

Thanks,

-Jamie

 

 

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ADC conversion attempted before the prior conversion was complete (NI-9219)

June 13, 2018, 9:14 pm
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While measuring voltage using NI9219, it suddenly shows this error and stopped the measurement.

After that, the same error shows up when I try to run the measurement.

Measurement was fine with the setup, so I dont think it is the setup problem.

Please help me, thanks.Capture.JPG

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Setting symbol for conditional disable without using project

June 14, 2018, 1:39 am
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Hi,

 

I want to set new symbol for Conditional Disable structure without having the VI in a project( that is without using project).  Can anyone suggest ways to achieve this functionality?

 

Thanks in advance.

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Issue in moving 32 bit Labview project from 64 bit machine to 32 bit machine

June 14, 2018, 2:13 am
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Hi ,

 

I am trying the copy Labview(32 bit) source code from 64 bit machine(windows 8) to 32 bit machine(windows).

When i opened the project in new 32 bit machine few of the vi.lib files are not recognized and they are all listed in the dependency list. Can anyone let me know what could be the issue.

For example , the below is not recognized by the project.

C:\Program Files (x86)\National Instruments\LabVIEW 2017\vi.lib\addons\database

 

Attached is the reference.

 

Regards,

Anand

 

 

 

 

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plot multiple graphs from excel table

June 14, 2018, 2:37 am
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I want to plot multiple graph which collect data from excel file where X axis is fixed in the range of 1 to 50. I want to compare different 50 data of Y axis. what can I do for this?

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data acquisition for optical set up

June 14, 2018, 3:23 am
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Hi! 
I'm just starting out in Labview with very little programming knowledge. I need to use Labview to control and get data from an optical set up. My set up has 3 main parts that require to be programmed. First I have a laser diode controller. I need to control the current via this system. This is already been done. 
Next I have a rotation mount ( thorlabs K10CR1). The control of this system has already been done using the Kinesis software. Finally I have a power meter, which is thorlabs PM16-120. All I understood about this system is that it comes with a software which displays the parameters when connected. I need to integrate the 3 components. I basically have to control the rotation of the mount (say we start at 0 degree angle), change the current, record its corresponding power. and this process has to be repeated from 0-360 in the rotation mount. Its basically a loop. and this data has to be recorded for analysis. 
However the issue is, I have no idea where to start. I have no technology background and its making it really hard for me to understand what some terminologies mean. For instance, the rotation mount uses .NET, i don't know what that is. and the laser diode current control is through something called VISA. I don't get that either. 
Any help will be appreciated! 
Please be kind since I'm a complete novice. 
Thank you very much. 

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WinWCP files for Electrophysiology

June 14, 2018, 3:33 am
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WinWCP is a free software by John Dempster for acquiring electrophysiology data: http://spider.science.strath.ac.uk/sipbs/software_ses.htm

As it is broadly used in my work, I wrote a set of Vis to read the .wcp files in Labview. The format is quite simple & straight-forward, it seems to work fine but do not hesitate to tell me if you spot any mistake. You can check the file documentation on the website. If you use this reader, please cite the DOI showed in this link: https://www.researchgate.net/publication/323548202_WinWCP_Labview10

The file available here is for Labview 2017, but the file available in the ResearchGtae link is for Labview 2010.

Cheers!

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The compilation failed due to a Xilinx error.

June 14, 2018, 5:56 am
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Hello, 

used hardware: Compact Rio 9035 and NI 9853. 

used software: Labview 2017

When i compile the VI "CAN Signals Transmit FPGA.vi", i have this message: 

 

LabVIEW FPGA:  The compilation failed due to a Xilinx error.
 
Details:
ERROR: [Synth 8-1031] cincorrectmodule is not declared [/opt/apps/NIFPGA/jobs2/VWAs7wP_K2iuqv0/Slot_4.vhd:6637]
INFO: [Synth 8-2810] unit behavioral ignored due to previous errors [/opt/apps/NIFPGA/jobs2/VWAs7wP_K2iuqv0/Slot_4.vhd:6555]
INFO: [Synth 8-2810] unit propertycontrolp1slot_4 ignored due to previous errors [/opt/apps/NIFPGA/jobs2/VWAs7wP_K2iuqv0/Slot_4.vhd:7080]
---------------------------------------------------------------------------------
Finished RTL Elaboration : Time (s): cpu = 00:00:06 ; elapsed = 00:00:32 . Memory (MB): peak = 1014.520 ; gain = 177.285 ; free physical = 28246 ; free virtual = 29434
---------------------------------------------------------------------------------
RTL Elaboration failed
INFO: [Common 17-83] Releasing license: Synthesis
9 Infos, 4 Warnings, 0 Critical Warnings and 2 Errors encountered.
synth_design failed
::RTL Elaboration failed
    while executing
"source -notrace ./.Xil/Vivado-2344-ip-10-0-53-140/realtime/toplevel_gen.tcl"
    invoked from within
"synth_design -keep_equivalent_registers -top "toplevel_gen" -part "xc7k70tfbg676-1" -flatten_hierarchy "full""
    (file "/opt/apps/NIFPGA/jobs2/VWAs7wP_K2iuqv0/synthesize.tcl" line 21)
    invoked from within
"source "/opt/apps/NIFPGA/jobs2/VWAs7wP_K2iuqv0/synthesize.tcl""
# exit
INFO: [Common 17-206] Exiting Vivado at Thu Jun 14 12:43:31 2018...
 
 
Compilation Time
---------------------------
Date submitted: 14/06/2018 14:42
Date results were retrieved: 14/06/2018 14:45
Time waiting in queue: 00:19
Time compiling: 02:49
- Generate Xilinx IP: 00:00
- Synthesize - Vivado: 01:41
 Please, can you help me! 
Thank you in advance. 
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CIFIX 50E-DP slave Driver Handling Problem.

June 14, 2018, 6:00 am
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I also have problem, with handle, the CIFX 50E driver handling in Labview, because for windows 10 driver has changed
significant. I dont know, hogy should i handle pointers, C typedefed structures, values of structures. I dont know, how
sould i read the values of conllex variable (wich defined in dll) if i only have returned pointer in Labview.
I found worhking examples for the old Cif32dll.dll, but for windows 10 the had write the new cifX32DLL.dll (significant
changes).
Should you give me any help, or any example/solution?
I sent informations, driver documentations, and other materials.

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Writing comment to a tdms file during Data Acquisition as many times as required

June 14, 2018, 6:08 am
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Hi everyone,

I am trying to write a comment to a tdms file during Data acqusition at deasired time stamp.(Please find the attached doc).One which I did was able to write the comment only in the first cell of the Comment column.

I searches in the Forum about this Topic and found that qeueing is the solution and found no vi's related to it. Please help with a example to start with it.

 

Thanksa a lot in advance

 

 

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Trigger from digital input - DAQ acquisition time control issue

June 14, 2018, 6:25 am
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I have a digital input from a PLC, that lasts for ~15seconds, i want to log data independent of the trigger state however.  Right now i have the digital input wired to a case structure, although i can time my DAQ loop to collect data for a given time i get multiple DAQ files for any acquisition time less than 15s.  

 

i want to trigger form a lead edge on the digital input signal line only, how do i ignore the state and only focus on the lead edge?

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FPGA with cDAQ board?

June 14, 2018, 6:32 am
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 Greetings,

 

 I'm using NI cDAQ-9189 with NI 9402 module for digital I/O, but I found that FPGA may be useful for my application.

 

 However, I'm worried about cDAQ-9189 does not support FPGA. Do anyone know about it?

 

 

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Missing File for cRIO Acceleration and Strain Sample Code

June 14, 2018, 7:00 am
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Hi all,

 

I recently downloaded an archived file (cRIO Acceleration and Strain Data Logger Reference Example (Archived)) from the ni website and ported it to my cRIO 9024 (with a 9113 chassis) and it appears a file is missing. It loads everything and asks for Burton.lvproj_FPGA Target_FPGA VI.vi.lvbit. This then messes up my RT and FPGA vi's (see the attached image below ), rendering the code un-usable. Does anyone have this file, or know where to find it? I have all of the components (9233 and 9237 cards) and a project file with the files from the downloaded added under the cRIO.

 

I'm running LabView 2014 SP1 and the cRIO is updated to 14.5, for reference.

 

I looked through the source code from the download link and it was not there.  

 

Thank you for any information you can provide!

 

FPGA and RT Error message.PNG

 ^error message received in the FPGA and RT vi's after deploying all^

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How to remove noise from the acquired signal?

June 14, 2018, 7:45 am
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Hi,

 

I am measuring the output of 4 strain gauges. NITB-4330 front block mounted on NIPXIe-1073 chasis has been used as DAQ device. I am getting some weird signals. I want to know is there noise present in the output? What would be the possible source of noise? How can i distinguish between noise and actual signal?  And how can i remove noise? Does noise has anything to do with sample rate? I have attached output of strain gauges for two different sample rate. I am new to LabVIEW and concept of noise.

Thanks in advance,

JP

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XY Graph: Visible Data Only

June 14, 2018, 8:59 am
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Is there a way to directly retrieve only the currently visible data (within X and Y scale limits) from an XY graph, perhaps from a property node? I couldn't find any documentation on XY graph's properties from NI.

 

Alternatively, what's the best way to conditionally index an array in LabView? I can only think of inelegant ways to accomplish array conditional array indexing in Labview, but surely there must be a good way to do this.

 

 

In python I would do:

    y_visible = y[(x > 3) & (x < 9)]

where the X axes limits are 3 and 9. This line gets the subarray of y where x is between 3 and 9.

 

Thanks!

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Filling array with indexes of non-zero elements

June 14, 2018, 9:07 am
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Hello,

 

Applying 8 digital waveforms, I'm trying to create 8 arrays of index where bit = '1'.

For simplicity in the code below I process only 7-th (last waveform).

The lenght of array should be less than waveform length , because the number of '1' is less than waveform length.

The output is a little bit strange.

If i-th bit is '1', its index is added to array ... it's OK.

But what is wrong - if i-th bit is '0', nothing must be added to array, but in my case 0 value is added.

Thanks in advance.

Pavel.

 

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Export restrictions (ECCN/EAR) for custom labview programs?

June 14, 2018, 9:25 am
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Hi all,

 

New here. My company has been asked to develop some custom labview code to measure medical device performance.  Does anyone know if any sort of export license or restrictions exist to send the code from the United States to China?

 

Thanks.

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Acquiring data for multiple UUT that is triggered from an external instrument through GPIB

June 14, 2018, 9:57 am
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Hello,

I am using Labview 13 to create an automated system that measures the voltage of multiple pressure transducers (at the same time) at various pressure values. I have: PXIe-8102 embedded controller

NI PXI-4065 DMM

NI PXIe-2527 Multiplexer

PXIe-1075 chassis

The pressure controllers I am using are connected through GPIB and communicated with through GPIB commands. (Mensor 8201, DHI PPC3)

 

I want to trigger the voltage measurements of the UUTs with a signal from the pressure controller saying it has changed pressure values, take measurements of the UUTs, wait until pressure controller has changed values and then get triggered to take another measurement and so on...

 

My understanding is that I can use NI SWITCH and NI DMM using handshaking to take measurements of multiple channels and parse these measurements to assign them each to their respective channels for display. However, I'm not sure how to use the GPIB to trigger the measurement.

 

I'm fairly new to LabView so I'd love to know if I am on the right track.

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Simultaneously Reading and Writing problem NIDAQmx.h

June 14, 2018, 10:52 am
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