I was trying to update the excel File continuously. The excel file opens and updates without any problem when i don't click any of the cell in the excel sheet. while during the excel update When i click any of the cell it is skipping few rows or columns in the update process. why this scenario is occurring. when it is checked for the error it is stating error -2146777998. Can anyone clarify.
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Excel error -2146777998
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Labview Video processing
Hii,
I am trying to subtract background to the image frames of a real time video. The video consists of a human and I only want the human image after the background subtraction. Can anyone please suggest me a method to do it.Thanks in advance.
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Writing data to a string using case structures
Hello Guys,
i' ll try my best to clearly explain my problem and code. I am reading a couple of RFID tags, either at the same time or 1 by 1. to do that i created a dummy array to compare my original array to determine weather a new tag was discovered or not. if it is discovered then i enter a description of it using a pop-up and i re-append the original array to the dummy one. My problem is writing the user input'ed data to a string array, now because of the case structures i have to write a value in the true AND false conditions. However, i do not need the false condition to write anything to my array. what can i do to have labview ignore that false case? and just write a value when the true case is indeed true?
I attached a snippet of my code, it has descriptions all over it, so it should be pretty clear.
Thank you in advance,
Fadi
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Temp reading with optris cs lt
Dear Labview community.
I have a problem regarding the temperature reading in labview using the optris cs lt sensor.
the sensor is set to burst mode. (meaning it only sends data) using a string like the following example: \AA\AA\04\D3.
\AA\AA are 2 synchronisation bytes and the rest is temp data.
the vi i provided you with is working and sometimes reading the correct temp but most of the time it's off. because on every other turn it takes one or both \AA and thus after converting the temp is something like 4000 °C...
do you have any idea whats wrong or how i can get rid of the wrong reading?
best regards
octaris
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HC-SR04 with Arduino and NI-USB
Hello,
I am trying to measure water level in a tank using HC-SR04. First, I tried using Arduino UNO but it always showed a constant value (48). After that, I tried NI-USB 6009 and NI-DAQmx. It also showed error. I have attached both VI here. Would any one help me to solve the problem, please?
Thanks in advance.
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New to Labview and struggling
Hello,
I am sorry if I will come off as ignorant or just plain dumb because of this easy problem. I just started using Labview last week and I don't get the grasp of it yet. I started with simple applications and I wanted to build a temperature converter from K to C and F, and F to C and K, C to K and F, but I cannot seem to find a way to connect two wires to one thermometer (by doing two different arithmetical operations), maybe I need to go deep down into programming, but I am not sure. If any of you could help me and give me a little push so I can get this done, I'd be very grateful to you.
I made the basic conversion from F to C from one of the NI tutorials.
Hope my explanation wasn't too difficult to understand. Also, I am using LabView 2015.
Thank you a lot in advance and have a nice day!
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Communication between 7852R and BNC-2121
I am trying to use the RMIO port to interface with a BNC-2121 box from a PXI-7852R. I have an adapter cable, 189588A-01, that should allow me to use the devices together based on the datasheets. However, when I connect them through Connector 0 (RMIO) I do not get any response; even the PWR light on the BNC-2121 is dark. Do I need to activate the system in some way? What am I missing here?
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Using LabView to controll a Heat Exchanger
I believe i've made a correct working program in LabView to control a heat exchanger but have been unsuccessful running the machine in remote mode. I'm sending a 24V signal from a power supply through a NI 9482 electromechanical relay and can't seem to get it to turn on. I'm measuring the correct voltages to the correct pins at the equipment plug but nothing happens when I turn them on and off. Does anyone have an idea of what could be going on?
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Is there a work around for not having access to conditional symbols in build?
This idea relates to a very common IDE feature that allows you to set symbols per build. Strangely, Labview only allows you to have one project configuration you must manually change, unlike say Visual Studio. It does produce different builds. But it doesn't connect the two by allowing you to specify project symbols in the build.
There apparently was a work around in this idea exchange above, but it both doesn't seem to exist anymore and according to one user doesn't work post 2013. Does anyone have a new work around for this, perhaps with pre-build actions? Seems like you'd have to use a VI to clone the project and update the symbols in the new project. Run the project and run the build. I dunno, seems cumbersome. We have 10 or so symbols each with 2-3 values so manually updating them is not optimal, especially since the conditional symbols don't use a drop down to select. You have to manually type their values. I'm using 2016 at the moment.
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Programmatically Control Latching Boolean
Hi,
I am relatively new to labview without foundation, so please understand my shallow knowledge.
I am working with an example VI that was provided with the hardware, which is a dual syringe pump.
The example VI has a big case structure with different boolean controls and each structure dictates what action to take when the boolean is selected on the front panel. All the boolean controls are latch mechanical action.
So, what I want to achieve is to programmatically control one of the boolean controls that when one control is selected on the front panel, it will execute the program written in that corresponding case structure and also turn on another control to carry that function as well. Basically, the first control would be used to initialize the values in the second control.
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Keithley 27XX Error 170, 101
Hello,
I work with Keithley Libraries 27XX. We have to connect the list with channels, like string separate by comma (like in 1LV attacment. I mean we have to chose string constant from palete, and type manually), but if I connect like indicator, there is a error (170 and 101, 2LV). I suspect, it can be problem with strings formats. If I would copy from indicator, and would paste to constant, It would be no problems. Do You have any ideas? Thanks in advance.
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Problems meassuring rmp
Hi!
I have to measure the rpm of a propeller using a Brushless RPM Sensor, and I have two questions:
1- I have a NI 9401 which allows me to measure it, but I wonder if I could measure it with another NI 9205, and the PF0 pin that it has, I can configure it but it doesn't work, I am selecting the daq_ctr0 as counter, and the 9205 PF0 as frecuency terminal.
2- I get a graph where I can see the pulse train who is generated by the rpm sensor, but I can't get the frecuency, I haven't found any tutorial about how to get the frecuency of a pulse train. I also have problems with the number of samples, because if I select a low number, it doesn't work when the propeller is at maximum P, and if I chose a bigger one, it doesn't work with the lowest rpms.
Thank you very much, I have attached the code.
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vi loading problem
i have a labview VI that i have been using for a few years and i just got a deployment error (see attached .JPG). can someone direct me on how to solve this problem?
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Send and receive a signal using daqmx and asynchronous call
Hi to all,
I have attached a vi to send and receive a signal from data acquisition device, however i can control the sampling rate or i can send a signal to the call vi but i can't receive the reading signal back i don't know why?
is that somebody can explain about this?
Thanks in advance,
Regards,
Dinesh
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captions
I was wondering if possible to write to a caption while vi running? Asking because thought convenient way to save/change comm commands associated with that object. Thankyou
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Remote Control for Labview
Hi,
I am looking for a remote control device which can be used in Labview. What I will need is something similar to TV remotes. I am planning to define events on the buttons of remote and do the corresponding actions in my VI.
There are some remotes which are used for presentation purposes like this one: https://www.amazon.com/Logitech-Wireless-Presenter-Presentation-Pointer/dp/B002GHBUTK
It would be very helpful for me if there is anyone who tried similar thing. Is there any device which you can suggest me for this purpose or how can I interface that kind of presentation pointer with Labview?
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Filtering an Analog Input via a Timing System?
Hi all - LabVIEW newbie here. I am working on a photodetection system with three alternating LEDs all being detected by one photodiode. I was able to configure the alternating lights by creating a system where I can control the duty cycle and frequency of flashing for each of them all on the digital output of my DAQ. The problem I am having is separating the signals as they come in to my single photodiode. I have it hooked up to read the incoming voltage as an analog input, but want to be able to split the data output by time segments (to correlate/synchronize with the flash of each light). In the end I would like to have the readings from each LED separate from one another, but I cannot find a filter that can be manipulated via time or duty cycles. Please let me know If you have any suggestions!
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OLE VARIANT from COM ActiveX to LabView Variant
Hi there!
I have an ActiveX COM method (written in C++) which consists of the following definition:
HRESULT GrabToArray( [out] VARIANT* output_array );
The method allocates a two-dimensional array of type VT_UI8, ie. 64-bit elements. I can confirm the OLE VARIANT is passed out correctly, containing the 2D array, using a C++ test program. However I'm struggling to do the same in LabView.
I am using the Variant to Data function in LabView. The type parameter is an array constant of two dimensions of type U64, and the output parameter is an array object of two dimensions of type U64. It looks like this:
The Variant Indicator reports VT_EMPTY, which I don't understand:
And then the Variant to Data function obviously fails and reports a type mismatch.
I'm confident the VARIANT should contain the array, as I can debug the method in Visual Studio and see it successfully passed out in C++:
This makes me think I'm doing something wrong in LabView - where am I going wrong?
Many thanks,
Paul
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Data Acquisition with DAQmx Read in a parallel loop does not write all samples after first run
Hi everyone,
So I've got my valve timing pattern in a state machine and then I want to read/write pressure (and eventually add more channels in an array) in a separate loop. There aren't any race conditions so it should be fine its own parallel loop constantly reading/writing data the entire time with a wait time of 100ms.
For some reason the read/write only functions properly in the first run, writing about 90 samples in 20 seconds which is enough for now. If you re-run the program it only writes one sample to the next file for some reason.
This might have something to do with the way the analog read is setup, but I can't quite figure out why it doesn't "reset" on the next run even though I have it being cleared. Please let me know if the reading is set up wrong and how I should go about setting it up for a continuous read/write the entire time the program is running.
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Writing TDMS to CSV, how to define data type
Hello,
(customary I'm new-ish to LabVIEW intro paragraph)
I'm working on updating the current program to output a CSV. The original coder exported the data via a TDMS file, and I'd like to preserve this so all I want to do is read from the TDMS to make a CSV. The TDMS is nothing fancy. It's two different tabs (worksheets), and then in each tab, a metric ton of data in about 10 different columns.
I tried working through this forum post in order to do so, but I got stuck. https://forums.ni.com/t5/LabVIEW/Convert-TDMS-to-CSV/td-p/2735395
The largest problem I'm currently having is how to define the data type for the TDMS. Obviously, I need to output the data from the TDMS Read into a 2D array for the CSV Write, but I'm not sure how to tell the TDMS write function how to do so. Even though this won't show much here is a snapshot of what I currently have.
Also, to answer your question, no I can't post my entire code because it's proprietary; however, all that really matters here is that I want to take the data that is in the TDMS after all is said and done, and move it over to a CSV for easy analysis.
I appreciate your help. Thanks much.
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