Merge with actual request
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Labview 5.0 to 9.0
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Square wave frequency, daq
Hi,
I'm using DAQ mc 1208LS to get square wave(tachometer signal from pump), and for few days I'm trying to some how measure frequency.
Using examples I was able to connect and get strip charts, but I have no idea how to measure(count?) frequency.
Also my knowledge of LabView is extremely low...
Thanks in advance for help
J
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Measurement Abstraction Layer
I am developing a Hardware Abstraction Layer (HAL) for DMM at the moment. The parent implementation (DMM) is empty and has a single Dynamic dispatch member VI for acquiring data from the instrument. The output datatype however can differ such as a Number,numeric array or a waveform. The type of acquisition is configured using a enum early on from Teststand. The child class implementation (NiDMM) also has a single Acquire VI which runs a case structure to determine the type of acquisition based on the enum, and the data is written to the DMM class's private cluster. If I want to use this acquire VI within teststand in a Limit test step, I have to also call an accessor VI with in the wrapper VI to access the saved data at the end of the acquisition process.
Is there a better work around for this?
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TCLK Multiple Channels on Multiple Cards (with independant waveforms for each channel)
I have recently installed NI FGen 18.1 which adds TClk support to the 2x NI PXIe 5123 AWG cards that I am using.
I am attempting to synchronise and trigger the oscilloscope card (5170R) and the two AWG cards (5123) simultaneously, with an independent waveform being transmitted on each of the 2 channels on each AWG card. This should mean that I can trigger the oscilloscope and 4 waveforms simultaneously.
I can currently trigger all 3 cards to work, but I cannot get both AWG cards to trigger BOTH AWG channels as well, only a single channel.
If I configure each AWG channel independently, I can load on the waveform no problem, but when it comes to getting the Session Ref for the TClk Configure Homogenous Triggers VI, the session ref for 2 channels on the same cards will come back identical Session Refs, which will throw out an error.
If I try to use one of the channels to get the session Ref, it won't trigger both channels, even when they both have identical session refs apparently.
To get around this I considered configuring both channels on the AWG together, the same way you would configure the channels on the oscilloscope. So I use ' 0,1 ' as the channel name so I can configure both channels. But what I can't do is work out how to load a separate waveform onto each channel. If I attempt to use ' 0 ' as a channel name to put a waveform on channel 0, I get an error basically saying that the channel name for that is different to the channel name used when configuring the AWG.
So... I basically need to find out how to use TClk to trigger both channels on both cards and the oscilloscope card all simultaneously.
There must be a way to do this, I have checked most of the examples provided for TClk but none of them deals with loading independent waveforms onto separate channels on the same card.
Hope you will be able to help. I have attached my program (in the state in which I configure each channel separately and try to use Session Ref to use TClk )
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Lock-in amplification (1f and 2f simultaneously)
Hello everyone,
I am currently in an internship about frequency modulation spectroscopy. I would like to have a lock-in detection on labview. The objectiv is to obtain signals 1f and 2f simultaneously in a simple manner. I'am a beginner on labview and the internship is relatively short... Can someone help me ?
Thank you in advance for your answer.
Nicolas
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buenos dias , disculpe alguien me podra proporcionar el diagrama para hacer un tacometro con arduino y labview, hice comunicación con Lifa base, y quiero medir las vueltas con un foto diodo y un foto transistor por favor
ESTOY PROGRAMANDO EN UNA PLACA MEGA Y CON FOTODIODO Y FOTOTRANISISTOR
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Question on Serial Communication
I currently have a torque transducer that sends it torque information with RS-485 serial. I have the data protocol and I am wondering if I can take the two data wires from the RS-485 interface and wire them directly onto a BNC connection to acquire the data? I have a power supply to excite the transducer with 12V.
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Very strange: Front panel freezes in while loop and case structure sometimes
I encountered a strange problem: when I run a while loop inside an event structure, the front panel freezes. I have been using similar structure many times, and they all worked fine. So I stripped the program down to bare minimum, and it still doesn't work. But when I stripped down a previously working program, it still works. I cannot figure out what might have happened. I run them on the same computer, same version of LabVIEW (I tried both 2013 SP1 and 2016, and got the same results).
Attached are 2 virtually identical simple test programs. After they are executed, the "Big loop" counter will start running. Then when you press "Run", the program starts the waiting loop until the "SET" is pressed. In the working program, the panel is working while waiting for the "SET" button to be pressed (for example, you can still change the A and B values. In the other program, the panel freezes, you cannot change A and B values, but the wait counter is running.
Any idea why such strange phenomenon happened? Thank you very much!
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Different Pictures in a cluster array
I have a cluster that has one picture box one numeric and two strings. I placed this cluster into an array so I can keep track of some times. I can change the numeric and string for each array element. When I change the picture it changes the picture for all of them. Is there a way to have a different picture for each array element and not have a picture array?
Also why does the picture control act differently than the rest of the controls? Seems inconsistent
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Rotate XY graph to present feedback to user
Hi there,
I am capturing changes in thumb position using an accelerometer. I want the user to create a movement, and to try and match that movement to a target movement displayed on screen.
When I plot my target movement array and the user's movement array they are tilted to the side (with respect to veridical) so the feedback is hard to understand.
I read a bunch of forums and all I can see is suggestions to A. turn the XY plot into an image, then B. use this VI someone posted to rotate the image as desired.
I have done this and it looks pretty awful - largely because I can't work out how to remove the edges of the graph where you can see the axes all turned sideways. Also I can't quite work out how to take it off the loop to rotate with the slider without it stopping working (sorry, I am new to labview...), I just want a constant rotation of 160 degrees.
Is there a better way to do this that anyone can think of???
(final thing for bonus points, I would love to put extra lines onto this so the 'target movement' line is the top axis (0 degrees), but there is also a 90, 180, 270 line - where the target movement is rotated about its x axis by these degrees. I been trying to use a rotation matrix to do this but am failing miserably)
Harry
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Flashing Arduino file using labview
Hi, I am using ATmega2560 Arduino board and I want to flash a arduino (.ino) file using VISA from labview. but the program returns VISA write timeout (1073807339) error. Is it possible to flash arduino file from labview?. If it is how to flash the arduino file?
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How to retrieve original settings of "Read from spread sheet" VI ?
Accidentally i have changed some settings in read from spreadsheet .vi in my LV 2014. Now i cannot connect choose file path to read from spreadsheet .vi. Actually i changed file path option. Can anyone tell, how to retrieve original read from spread sheet vi from LLB manager? My LV code is shown in following figure.
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NI-DAQmx driver support missing after updating LabVIEW
I used DAQmx with LabVIEW 2016. However, evaluation edition of LabVIEW 2018 cannot find DAGmx 18.0. I removed DAQmx driver and reinstalled but it is still not working. What is the problem?
I attached error message which appears when I open vi using NI-DAQmx.
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count pixel
Hello all ,
i need to find the percentage of Pixels and number of pixels in intensity range in LabVIEW only . as like the "count pixel " function in the NI VISION BUILDER AI .
i tried with the Imaq histogram and imaq get pixel value . pls suggest me a options .
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Unusual problem with application
Hi labview-community,
I will try to explain my problem as simple as possible.
My application contains only 1 string control, 1 time control, 1 numeric control in 1 while loop refresh every 250ms(no events, no other controls) .
When I try to open .exe everything is ok, I can modify the value inside the string control.
The problem occurs when I click somewhere around app(desktop for example), at the moment application stops to react. Wherever I click in the app it doesnt react at all, but works( i can see the increasing value of timer control)....
It happens only in 1 computer station(DELL, Win7 x64), but unfortunately this one is the computer of the service guy.
There is no errors during working, it just doesnt react when someone wants to enter data to string control/ numeric control/ actually any kind.
I tried with other applications wrote by me, and all of them have the same behaviour in this 1 station. User is not able to enter data after click around app, after minimalize it etc..
I assume the problem is outside Labview but no guarantee. Installed all libraries.
Anyone had a similar problem?
Thanks for any help.
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Write in output DIO d-sub db25
Hi to all,
I am using a industrial PC which have incorporates a DIO d-sub db25 port wich has 8 outputs:
How can I program output 1 with labview? I mean open/close de output (0 or 1).
Thanks a lot.
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TCP 2230 no connection
Hi,
I have a Problem with the Touchpanel TCP 2230. We worked with it for 2 months now and have runtime on it. And now suddenly we cannot connect with it anymore. We don't really see indicators for possible errors and are desperate.
One thing that is unusual is that when the touchpanel is started, a NI program is searching for a document. We think that the program is NI Labview Remote Developement but we don't know what it is searching for because it only says: "choose a file" (like in the picture)
Do you know something about this?
Best regards
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Create New Instrumentr Driver Error
Hi All,
I have a temperature forcer that has no driver available. I have downloaded a driver for another manufacturers temperature forcer in hope I can modify it to suit the machine I have.
The driver I downloaded from NI is Temptronic TP04310. When I use the Driver wizard to create a new driver using an existing driver I get the following error message.
Can anyone help to resolve this. The message itself makes no sense. It says to click "cancel" to correct the problem yet there is no cancel button?
I have been into the .lvlib and tired to see if there is anything in there to change but the options section is greyed out.
Using Labview 2017 64 bit on Windows 7.
Thank You
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Data Type is Disabled
Dear All,
I dont know if it is a labview problem or my fail.
I am trying to change the range in a scrollbar but i am having problem. "The data type is disabled".
Please, some one could help me on this issue?
Thanks
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Web Service Problem: "Couldn't connect to server"
Hello,
I have been using the Web Services in some LabVIEW Projects, and everything was working fine in the Development mode and Executable mode. I was publishing a Web Service and redeploying it as usual, when I was confronted with this Error Message: "Couldn't connect to server".
Even I tried publishing the "WeatherMonitor" example and it showed the same error message:
I checked further the Web Service Configuration settings and Previously it used to show all the published Web Services as below:
However, now it's only displaying the following error message, which means:
"The Webservice API key cannot be acquired from server. Make sure, that the server is online or that your User account has the "GetWAPIKey" authorization"
I want to understand what would be the possible remedies for such a problem.
I don't know if something would have been blocked by the IT or from a Firewall??!
Thanks in advance,
Ahmed
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