Hello,
In the attached VI1, I am trying to pass the cluster from VI1 to VI2, but the cluster elements doesn't update. Can you offer some insights as to how I can go about updating the cluster from VI1 input to VI2?
Thanks,
hiNi
↧
Update cluster in subVI
↧
Using C-series DIO module in SCTL with slower clock than top-level [FPGA]
Hey all,
I'm running into a problem that I've not had much success searching online.
I've got a 9030 chassis with an FPGA built in, top-level clock 40MHz. I've got an NI-9401 DIO C-series module plugged into it and set to be managed by the FPGA target. I need to count some linear encoders at exactly 10MHz, no more, no less. They are clocked and give an output in such a way that if I oversample or undersample, I get garbage.
If I create a SCTL and set it to a derived timing source of 10MHz, I get a code generation error that:
"The Read FPGA I/O Node for DIO3 is used in a clock domain that it does not support. The supported clock domains include: the top-level clock and any clocks that have a rate that is a multiple of 40 MHz, such as 40 MHz, 80 MHz, 120 MHz, and so on."
I tried a few ways to get around this; first I tried just using a while loop with a loop timer set to 4 ticks, but it then takes 9 clock cycles to execute the counting for some reason (though this code can compile in the SCTL with no problems). I then tried using the SCTL with a "true" constant wired to STOP as a hack for a "timed sequence" frame, and that definitely did not work.
Are there any strategies or techniques or settings somewhere to get around this limitation on the DIO that I need to sample at exactly 10MHz? I would love to do this quickly in software and get this rolling ASAP.
An image of the relevant section of code is attached, I'm happy to provide more stuff upon request.
Many thanks!
Maia Bageant
↧
↧
Why won't loops execute after assigning processors for timed loops?
I have 256 two-frame timed loops in my code. When I execute the code without assigning processors only 128 of the timed loops will execute simultaneously, however when I assign a different processor to each one (0-255) then only 4 will execute at once. Why is this? How can I make them all execute simultaneously?
Attached: two snapshots of code. 1 shows a small portion of the timed loops, and the other is the part of the code that communicates with an FPGA VI that controls the state of outputs (using a CRio-9066.) For the timed loops, the little sun icon is a sub-VI that generates values for the dt time delay of the timed loops.
↧
Unable to deploy my RT vi code on cRIO in scan mode
Hi,
I have been working on NI cRIO for past some time. Today I faced a peculier problem. I was able to make necessary changes in my RT vi and deploy it on the cRIO. Everything was working fine but somehow I started to get the message of " Unable to connect to RT Target ". I was able to ping my cRIO and connect to it initally but as soon as I started running my RT vi on it , the connection was getting broken. I was even unable to ping my cRIo.
I searched a lot on net and even tried to reinstall the software on my cRIO. THe error code was pointing toward the SVE, but I had installed the required software for network variable engine on my crio. I am attaching the screenshots of my project and the error messsages.
Please let me know how can I run my RT code again on crio .
THanks.
↧
incremental encoder on cRIO
Hello, I'm working on compactRIO 9012 and I want to calculate the angular position from an encoder, I have the NI 9505 as acquisition module, is there any predefined function on labview that calculate the angular position, I have seen some exemples that only uses DAQmx to do it.
help please.
↧
↧
Ocean Optics Spectrometers under LabView - Ocean Optics OmniDriver
Hi all,
I am trying to summarize most of the Tech Support questions in this thread that i have seen in the past months.
First things first:
The OmniDriver is made for coherent bit Versions of operating system, Labview and OmniDriver. This is regardless of the OS and valid for Windows and Linux OSes.Prior to getting LabView talk to any piece of external equipment, please ensure that you can talk to the equipment under the tools provided by the manufacturer. This is important not only for OceanOptics instruments, but in general. For OmniDriver, the verfication of the installation process can be verified by running the SpectrumTest32.exe or SpectrumTest64.exe (for Windows, please mind the OS bit version) from the OOI_HOME subfolder of the Omnidriver installation folder with a spectrometer connected. Please ensure here that the instrument is properly identified and no driver issues are occuring on OS level, prior to running the spectrum test calls. This should open up a window where a short program is executed that connects to the instrument and returns a table of data on your screen. If this is working then turn to LabView.
I have seen that many users use 32-bit versions of LabView on 64-bit operating systems. This creates issues with using native 64-bit architectures like OmniDriver 64-bit. The common error message here is a .NET error code 1074 in the .NET interface of the wrapper call under LabView. There are two options to solve this issue. The first would be to contact NI for a 64-bit version of you LabView suite which depending on the age of your license and license model may create costs or not give you a solution. If you really want to use a 32-bit version of LabView with the OmniDriver on a 64-bit platform you need to install the 32-bit version of the OmniDriver in a 32-bit simulated environment. Under Windows this is quite easy as you can select to run programs in compatibility mode of for instance WinXP SP3 32-bit. This correctly registers the 32-bit/64-bit interface layer of the operating system to not create buffer over-/underflow in the driver call.
The next thing is getting the .NET interface in LabView up and running. There was a change in the syntax of the .NET interface going from the .NET framework 3.5 (using .NET 2 syntax) to the .NET4 framework (using .NET4 syntax). This change rendered a lot of .NET functions unusable. . Depending on how current the .NET framework on you machine is this may cause an error in the .NET interface when trying to create .NET constructor nodes under LabView. On many LabView versions .NET2 syntax is initialized by default and thus the .NET interface in LabView and the .NET framework on your machine speak dialects that the other does not understand. The typical .NET error code for this is 1072.
The solution in forcing LabView to initialize a .NET4 syntax interface. This rather simple and needs a .exe.config file to be placed in the same folder as your LabView.exe and is explained in the knowledge base article (http://digital.ni.com/public.nsf/allkb/32B0BA28A72AA87D8625782600737DE9).
The .NET errors are all summarized in the table found under this link: http://zone.ni.com/reference/en-XX/help/371361J-01/lverror/misc_lv_error_codes/
Another common error is the .NET error code 1172 which is related to the location of your dll and the assembly trust concept. When using third party drivers, please ensure that you trust the driver. More on this can be found in the following knowledge base article on sine: http://digital.ni.com/public.nsf/allkb/B15CE9F2715434C386256D3500601878
↧
How to synchronize image refreshing and camera? (stroboscopic setup)
Hello everyone,
I have an experimental setup, which consists of a projector and a camera. I control the camera snapshot timing with LabVIEW VIs from the manufacturer. The projector is installed as an additional screen, so I can use WindDraw VIs from Vision to update the outputted projector image.
During one cycle of my program (duration: 2seconds) I want to take an image with the camera of a default projector image (0.4s) and then set a different image (for 1.6s).
My problem is that the camera does not take the snapshot immediately when issued (apparently there is some overhead, so I need to include wait times) and during the exposure, the projector image changes. I could increase the cycle length, but I would prefer to keep the measurement frequency high. Especially I would not like to increase the cycle length due to slow VIs.
In addition the output image is refreshed later than I anticipated. I read up on that and found that the LV GUI is not updated in real time.
So I wonder:
1) Is there an example VI that illustrates how control a stroboscopic setup?
2) Can I use LabVIEW for image refreshing or should I reprogram the image output with OpenGL?
Previously I have used Matlab for a similar purpose and did not encounter such problems. I would really like to stick with LabVIEW though, as the interface is more intuitive for users.
Kind regards,
Jan
↧
Comment enregistrer des données à l'aide d'un bouton?
Bonjour,
Je souhaiterais pouvoir enregistrer les données que je récupère via une carte NI. Il faudrait que l'enregistrement débute seulement quand j'appuis sur un bouton. Pour l'instant j'ai réussi à enregistrer lors de l'éxécution du programme.
Merci d'avance pour vos réponses.
↧
simple way to pass a signal between independant VIs
Set-Up: I am using one VI (modfied version of http://www.ni.com/example/29872/en/) to output a voltage signal to a speaker using the NI 9263 module. This VI runs independantly and simply allows me to adjust amplitude and frequency as I acquire data. I am then using a second VI to read/save data from an array of 8 pressure transducers, this is a standard VI which uses DAQmx components to sample from two NI 9215 modules.
Question: Is there a way to pass the waveform from the signal generating VI to my data acquisition VI? I would like to save it along side my data for processing later on. I could of course T-off the voltage signal and send it back into the input module, but this seems like a dumb solution. Thoughts? Simplest solution wins!
I can gladly obtain screenshots if people would like, but our lab PC is offline so I havent taken any yet. These really are simple straight forward codes right now, I'm hoping to make minimal modifications.
(I know I don't have any posts on here, but I will give Kudos/Select Answer)
EDIT: Even if you could just suggest functions/methods to look into, that would be helpful. I have the feeling I'm not using the correct vocabulary in my searches.
↧
↧
Fitting Gaussians with similar Means but different amplitudes/standard deviations
Hello All,
I'm trying to figure out how to fit my data with a summation of Gaussian curves some of which may be hidden by others. I have played with the 'Non-Linear Curve Fit VI' but I run into a problem when I feed it data that has the addition of two gaussian curves with similar means and different amplitudes/standard deviations. Has someone figured out a means of deconvolving similar gaussian peaks into their summated parts?
↧
problème acquisition sur PCI 6032E
Bonjour, je suis actuellement en stage de fin d'étude et il m'ai demandé de réaliser l'aquisition d'un thermocouple. Nous pouvons utiliser qu'une carte PCI 6032E directement et le logiciel labview. Nous avons beaucoup de perturbation et nous ne comprenons pas pourquoi l'aquisition est instable meme en filtre le signal avec un passe bas avant d'enlever les bruits à 50 Hz.
Avez vous une solution?
D'avance merci
↧
Question about the accuracy of the Gaussian Fit
Hi all,
I was having some doubts on the accuracy of the gaussian fit performed by LabVIEW and implemented the code in attachment to test it.
I made a distribution and made a Gaussian fit to it and extracted the average and standard deviation.
Then, I used the same distribution and padded it with zeros to the left and right and did a gaussian fit to the overall distribution.
I was expecting the average to change but the standard deviation to be the same, since the difference in the distribution are the zeros...
The thing is that neither the average (the average is a fractional value) nor the standard deviation are the expected.
Any hints on why this may be happening?
Thank you very much in advance!
Best regards.
↧
embedded sequence
I have a two-frame stacked sequence structure inside of a while loop. I want the sequence structure to execute repeatedly, but when I run the code it executes once and then the while loop goes off without executing the sequence again (see attached image.) Note this is on FPGA
↧
↧
Device Drivers Download Installation Issue
I am unable to download and then install device drivers from Feb 2013 or any of the newer ones for that matter.
When I download and try to execute the file
dcd_feb_13_1.exe
The self extracting zip file (with an icon 7z SFX) extracts and promises to launch the installer, but it does not.
The downloaded file then dissapears.(This part I cannot believe. It is sooo annoying!)
When I go to look at the unzipped image all is there except the root install setup files (huh?)
Why is this still happening since 2012?
I have been unable to get access to device drivers since Aug 2012 and I have had this issue on two different machines.
Does anyone here have a clue?
Thank You
↧
correct connection in max but error in labview
i'm trying to connect tegam 1830a power meter to labview using usb-serial port
the device act correctly in max, but in labview the read visa function gives timeout error
i send order *iDN? to the device , and its work in max but not in labview
↧
labview matlab tcp ip error when closing connection
Hi!
I have been working with tcp/ip where Matlab is the server and Labview is the client and now I am facing a problem related when closing the connection of Matlab before Labview.
The idea is that if a problem occurs while capturing data from the Matlab, lets say instruments of other functions,and the program is interrupted and the conexion is closed (from Matlab side), Labview does not handle it well into a point that continuosly poops up an error dialog and does not let me do anything more with Labview, until I literally shut it down with the window task manager.
Can someone explain me why? and how can I fix this please ?
Thank you
↧
How to realign elements of an array? Working with old Dynamic Data consumers
Hello,
I've got some code which was written with DAQ assistants years ago. I'm trying to use tasks and arrays for my producer now for speed and efficiency, but I'm stumped on one thing.
The consumers were written to have the data in a certain order - there's even a VI in there that selects certain elements and sends them to specific outputs. I previously took care of this with a simple VI that split the dynamic data, wired them to different order terminals, and then set it back to dynamic; Screenshot attached.
Is there a structure like this for array where you can break out all the array elements, reorder them and insert constants, and then put them back into the array? What this ends up feeding is a subvi that's an array builder which converts the DD to array and then reroutes it. Seems almost like what I'm trying to do could be done there, but it's a bit confusing to me.
Thanks in advance.
↧
↧
Open Web page errors
Hello,
My simple open a web page logic used to always work up until recently, but now I am getting the following LabVIEW errors when I run it and my application never opens Internet Explorer:
"Error -2147467259 occurred at Unspecified Error ..."
"Error -2146959355 Active X error"
LabVIEW 2012 August
Windows 7 32-bit
I am wondering if there is a Windows or LabVIEW service that was mistakenly turned off. I had some sluggish network performance and I ran the following recommended batch file:
http://digital.ni.com/public.nsf/allkb/814FEF952915137686257B6B006C5F4F
What service would cause this problem? I know it is related to Active X.
RobL
↧
Stretched Cluster Constant Bug
I found this on my diagram:
I don't suppose this is intended, but it is definitely cute.
Double-click on it back and forth and it reverts to the standard icon size:
How did I obtain this?
This is my quizz of today.
↧
Using comparison function where 2 arrays of different data type
Is there a way to use the comparison function in Labview where you're comparing 2 arrays of different data types (e.g. boolean and double precision)?
↧
