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Connecting to NI OPC server gives "Access is denied"?

February 6, 2018, 2:59 am
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In the distributed system manager (DSM) I can see that the local OPC1/NI OPC Client Status is Active=true, Connected=false.

When I enable diagnostics I get HRESULT=0x80070005 Access is denied.

 

| |-GetCLSID: ProgID=National Instruments.NIOPCServers.V5, Machine="", CLSID=0-0-0-00-000000 (FAILED, HRESULT=0x80070005 Access is denied. )

 

I have been playing with the settings for both Component Services/DCOM and Services/NI OPC server & NI OPC server AE. People say that I should "run as interatice user". That is now available, greyed out for some reason. I suceeded to set a named local user for both Component/DCOM and Services/NI OPC, but no improvement. Also a working setup on another PC has both users as system=default.

 

Any ideas?

 

Earlier post: OPC server 2012 cannot connect to Labview 2012 most of the times?

 https://forums.ni.com/t5/LabVIEW/OPC-server-2012-cannot-connect-to-Labview-2012-most-of-the-times/m-p/3750828

 

Diagostics from NI OPC server

OPC I/O Server Diagnostic Information

02/06/2018 11:35:19,617[Browse] Browse: (SUCCEEDED)
02/06/2018 11:35:22,268[Browse] Browse: (SUCCEEDED)
02/06/2018 11:35:24,947[Browse] Browse: (SUCCEEDED)
02/06/2018 11:35:27,618[Browse] Browse: (SUCCEEDED)
02/06/2018 11:35:29,697[Connection] SetGroupState (SUCCEEDED)
02/06/2018 11:35:29,697[Connection] Reconnect: (SUCCEEDED)
02/06/2018 11:35:29,697|-[Connection] Disconnect: (SUCCEEDED)
02/06/2018 11:35:29,697|-[Connection] Connect: (SUCCEEDED)
02/06/2018 11:35:29,697 | |-GetCLSID: ProgID=National Instruments.NIOPCServers.V5, Machine="", CLSID=0-0-0-00-000000 (FAILED, HRESULT=0x80070005 Access is denied. )
02/06/2018 11:35:29,708 | |-GetCLSID: ProgID=National Instruments.NIOPCServers.V5, Machine="", CLSID=0-0-0-00-000000 (FAILED, HRESULT=0x80070005 Access is denied. )
02/06/2018 11:35:30,268[Browse] Browse: (SUCCEEDED)
02/06/2018 11:35:32,637[Browse] Browse: (SUCCEEDED)
02/06/2018 11:35:34,968[Browse] Browse: (SUCCEEDED)
02/06/2018 11:35:36,907[Browse] Browse: (SUCCEEDED)
02/06/2018 11:35:37,637[Browse] Browse: (SUCCEEDED)
02/06/2018 11:35:40,287[Browse] Browse: (SUCCEEDED)
02/06/2018 11:35:42,967[Browse] Browse: (SUCCEEDED)
02/06/2018 11:35:45,628[Browse] Browse: (SUCCEEDED)
02/06/2018 11:35:48,287[Browse] Browse: (SUCCEEDED)
02/06/2018 11:35:50,957[Browse] Browse: (SUCCEEDED)
02/06/2018 11:35:53,627[Browse] Browse: (SUCCEEDED)
02/06/2018 11:35:55,387[ReleaseAll]: (SUCCEEDED)
02/06/2018 11:35:55,387|-[Connection] Disconnect: (SUCCEEDED)
02/06/2018 11:35:55,387[Connection] Disconnect: (SUCCEEDED)
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Slow remote debug

February 6, 2018, 3:01 am
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Hello,
I'm experiencing very slow start-up of remote debugging sessions. When I'm on a local network, it takes some seconds to get the control on the application when the main VI starts downloading (21MB). However, I have sometimes to debug applications running on far away sites (from Europe to Asia or USA) and in this case, it takes sometimes about 20 minutes before I'm getting the control on the application. I don't think the internet download time is the only reason for this slow start-up. Is there any configuration or best practice to speed-up the remote debug? 

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Cronometro

February 6, 2018, 3:08 am
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Converting Modbus integer to float

February 6, 2018, 3:56 am
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I'm working on a VI that controls an electric motor through an Emotron AC drive, using the modbus library. I have no problem getting the motor to run and read its speed, however when trying to read the torque i get a problem.

 

It seems the Emotron drive is using its own format for floating point numbers, see attached page from the manual. So when reading the torque in Labview i get a number like 65431 something, how can I convert this to floating point using the method descriped in the manual?

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How to find 'set of pixels' inside each blob of a AVI.

February 6, 2018, 4:57 am
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Hello All!

I want to find the set of pixels inside each blob(in my case: they are circles) in an AVI file/ a image. I am aware that by using IMAQ Particle Analysis VI, I can get the number of particles detected and also a 2D Array of requested measurements of the particles. From there, I can easily exrtract the 'First Pixel X and Y' , 'Centre of Mass X and Y' ,'Area' and also the 'Perimeter' of the particles. But,I also want all the pixel coordinates inside each blob .

Can someone give me a hint or help me out how to extract all the coordinates of the blob? 

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head mounted display

February 6, 2018, 5:47 am
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I have an idea to implement head mounted display in LabVIEW.I saw some videos and have an idea to implement it in labVIEW.Is it possible to do it.

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Collecting Temperature Data Over a Long Period

February 6, 2018, 6:04 am
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I am creating a temp monitoring vi that will display temps in real time on a waveform chart. I have done a similar project before using a thermistor. What is different this time is that it need to log temperatures over the course of a week so I need to limit the number of data point I take. I would like record the temperature something like every 10 minutes. But I don't want just 1 data point collected every 10 minutes. For example, on the 9th minute, I want to start collecting hundreds of data points and then report the average temperature on the 10th minute.

 

I understand the process of setting up the thermistor circuit and collecting the data. I'm looking for the most efficient way to get the timing part right. Thanks! 

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FPGA Referencing Multi Loops

February 6, 2018, 6:24 am
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Hello,

 

I have a simple VI which open's a FPGA Reference (using Open FPGA VI Reference) in dynamic mode, downloads to FPGA and runs it.

This is done before a timed loop starts and then the reference out of the Run invoke node is passed to do operations such as read and write.

All this is fine and dandy.

 

The issue I have is that I have another loop, which is significantly larger visually and the process of passing the reference wires around is a total nightmare. Usually when i come to these in files i put the file reference to a control and then use a local variable to reference it throughout making my code neat and tidy and simple to understand.

 

When i do the same with the FPGA initially it is fine. However when I rebuild the FPGA, which changes interfaces I have to delete the control and re-add it, which means all the local references I have need to be replaced. 

 

Ived tried using another FPGA dynamic reference, which works fine but puts a 75ms overhead on my loop which isnt acceptable.

 

What is the 'proper' way I am supposed to do this keeping in mind I need to quickest possible update rate.

 

Thanks in advance

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Snippets Manager - Drag snippet from LV exe to block diagram

February 6, 2018, 6:58 am
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Hi

I would like to create Snippets Manager which should work like this:

1. You have an app with a list of your snippets (see attachment).

2. You can scroll through all of your snippets and select the one you need for the particular task.

3. You can select the snippet from the list and drag-and-drop to the block diagram of some VI that you work on.

 

I started this project but in couple minutes I realized that I have no idea how to do programmatically attach a snippet to the drag action (that first issue) and then drop that to the block diagram which works in another process (second issue). I thought that this manager should be compiled into the exe.

Does anyone have any experience with such issues and is able to guide me somehow? Included examples with drag-and-drop action are related to transfer between controls inside the same window, so they are not so helpful for me.

 

Alternatively, maybe you have a better idea to manage snippets and mine is not worth any time.

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Reading UsedRange rows from excel yields unexpected answer from a particular sheet

February 6, 2018, 8:20 am
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I am trying to append data to exisiting data in a Excel sheet and I am able to do it. But there is always a huge cell gap between the existing data  and newly written data. I have used ActiveX to read the number of used rows from a worksheet. The workbook has 3 sheets and unexpectedly it reads wrong value from just one sheet (Historie) while other 2(Übersicht and testing) are read correctly. I have checked the Vi (check zip) with other excel sheets and it works correctly everytime except for the HIstorie sheet. Any input is appreciated

 

Excel: .xlsx ; Labview access: ActiveX

RowValue.jpg

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Acquisition and display of a frame given by external triggered camera

February 6, 2018, 8:49 am
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good morning everybody,

I am trying to acquire and then display a single frame from my Grasshopper3 by Pointgrey after that the camera is triggered by a NI USB 6221 DAQ; I don't know how to first "snap" and then to show this image.

I have made several attempts, all leading to some kind of error.

In the picture please find the snippet of my code.

The camera has been correctly initialised and set for triggered acquisition.

The subVI simply calls the DAQ and makes it ouput a digital trigger.

Any help is much appreciated.

Kind regards

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Use Single Process shared variable for control AND loging

February 6, 2018, 9:58 am
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Dear NI friends,

 

I use a real-time application (see attachment) with various VIs running in parallel on a PXI target.

In the Controlling.vi, sensor data are captured and simultaneously actuators are commanded both inside a Timed Loop. Also a Networking.vi is used for interaction with the user, e.g. chart monitoring and update of control setpoints. This vi communicates with the controlling.vi via single-process shared variables and with the user interface via network-published shared variables.

A third, Logging.vi is used for logging data and saving them on the PXI. After the test I can load the text file onto the host pc. My question is how should I log variables that are already used in the controlling.vi. Should I use a separate single process shared variable and basically capture the data twice or can I read the same variables that are used for communication with the networking.vi? I am not sure if conflicts can arise due to the fact that one variable will be read from two separate VIs simultaneously.

 Question_1.PNG

 

Best wishes,

Lysandros

 

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How to filtering signal of voltage data adquisition with "Median Filter"

February 6, 2018, 12:17 pm
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Hi, I am working with a displacement transducer, which I get voltage adquisition and a noisy signal.

I was trying to filtering signal using "Median Filter" but without success. Maybe I have a mistake using "right rank" and "left rank".

So I hope you can help me and get a better signal.

 

Attached the images and VI.

Regards.

 

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Labview NXG 1.0: Hardware missing from hardware tab

February 6, 2018, 12:54 pm
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Hello!

I have a problem getting my hardware recognized when using Labview NXG.
To be clear, i've tried a bunch of things to make it realize it is well plugged, but nothing has yet worked.

The devices i'm using are present in MAX:MAX.png
And i'm able to detect the captor and visualize the output from the MAX test pannel, however i cannot reproduce it using Labview NXG:

 

NXG.png

Here i only get the computer and the NI PCIe-8361 which is not used in my case...

 

 

At this point i guess this error is related to the DAQmx driver not working properly with Labview NXG, however i can't install any updates / driver with the NIPM, i always get this error : Server has closed the connexion prematurely:

 

update_error.png

I've also tried to install DAQmx from direct download, but it does not look like to have changed anything (I've seen a thread talking about a Labview NXG DAQmx related driver but I can't find anything looking like that online)

 

 

If you need any additionnal translation from the screenshot, just ask for it and i'll translate it in english Smiley Happy

 

Other things i've already tried at this point:

- Full uninstall, re-install (from the USB key packed with the hardware)


Thank you for your help and excuse me for any English errors, it's getting late here and i'm getting really upset about these problems Smiley Very Happy

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Should a simulated hardware device be a child or a sibling of the "real thing"?

February 6, 2018, 1:14 pm
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I'm just now getting started using the Actor Framework and am coming up with some "architectural" questions I hadn't really considered beforehand. Part of my code involves using various hardware devices, which need a custom simulation option- for example, a popup where a user can manually enter the values for an analog input.

 

What I'm wondering now is what the best practice would be for simulated hardware from an LVOOP standpoint. My first go at this had a "Data reader" actor (what I believe is called the "hardware abstraction layer") which had two child actors, a DAQmx one and a Simulated one, where a window would let the user enter the values. This works well and is all fine and good, but when I started working on my second one I started thinking if I should do a Simulated DAQ as a child (override) of the specific DAQ that it's simulating. My gut tells me they should be siblings, but I couldn't find much information on this (searching "child sibling object hardware" just gets me a lot of Google results about toys, haha).

 

As I'm not the first person to need this I am assuming this is mainly a "solved problem" and would love to hear what the best design pattern is for creating simulated hardware devices.

 

Any tips?

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NI-XNET and logging CAN messages to TDMS file

February 6, 2018, 1:50 pm
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Trying to follow the documentation trail provided by NI and feel like I am going round in circles.

 

I thought logging CAN messages to a TDMS file would be a bit straight forward! Our issue is we don't yet have .dbc files so want to log the CAN messages anyway (undecoded if you like) and decode them later when we do get the dbc.

 

From what I can gather you set up the NI 9862 module in MAX and you can assign alias's and things and then you refer back to this set up from the VI you make.

 

In the VI do you go for creating a session (so Frame Input Stream mode session) and then wire that on through to the XNET Read.vi (CAN Frame). That, according to the manual, would look like it would spit out an array with msg ID, time stamp, message payload etc. Is that easy enough then to feed into a TDMS writer?

 

Would Frame Input Single-Point mode be better so I could sample all CAN messages at a set interval (instead of just having them come as and when, obviously on a vehicle CAN messages are transmitted at different rates, usually dependent on how important the message is). 

 

Many thanks in advance for any advice proffered. 

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TTi CPX400 Driver Install

February 6, 2018, 4:00 pm
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I'm having some trouble with the drivers to remotely control a TTi CPX400 Dual Power Supply. I downloaded the first two drivers from this and from this link. MAX can find the instrument. I have successfully "Mass Compiled" the library, but it still won't come up on the functions palette. I noticed that there wasn't a LabVIEW Library Project in the folder, but I'm not sure how to go about making one at this point. 

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Graphing Data that was created by Daq card and placed in excel.

February 6, 2018, 6:18 pm
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I used a daq card and had the data put into excel. I was trying to graph it in excel but I am not sure what to graph since I have input (-10 to 10), output( -5 to 5), change voltages by .5, and then get the actual voltage. But what is it I graph out of all this information given to me from labview. 

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Regexp: how to get random string matching to specific RegExp?

February 6, 2018, 7:18 pm
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I work on labview application which needs to scan various bar-codes and match them to regular expressions from database. For testing purpose I would like to solve opposite task - be able to generate some random strings which are matching to my specific regular expressions. Strings are kind of long, up to 16 characters, various length, so dirty brute-force in while-loop until match found does not look like a good idea. Are there any better ideas?

Below is a sample of my regular expressions: [0-9A-F]{8}[0-3C]{1}[0-9A-F]{4}A:[0-9A-F]{1}

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[LabVIEW] Send CRLF as Termination Character in Serial Port

February 6, 2018, 7:53 pm
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Hello All,

Good day.

 

I am now facing the termination character problem when using serial port to send commands to instrument.

When I study the example(Example>Hardware Input and Output>Serial>Continuous Serial Write and Read), there is only one byte termination character(CR or LF) can be sent in every time. However, I need to send CRLF (\r\n) to make sure instrument can receive the command correctly, but it seems that LabVIEW doesn't support it. 

Could somebody give me some suggestions where I can find more information about this?

I had searched a lot of pages in community about CRLF, but I still can't find out the solution. Thank you!

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