Ring buffer

Hello

as in the topic, I want to set up a ring buffer. I have an analog-to-digital card and want to generate a signal to the outputs analog. Now I have two tables and start to fill one of them. When the picture is complete, I want to send to the analog output. In the meantime the second table should fill up.

This process reapeats until the end condition is reached.

I don't know if it is possible with Windows Lab and USB. PCI Express 6364?

Do anyone have an example of code for such a task?

Best regards

Hello

in general, this is not a complex application, you want to implement. In general, use one of the examples expedition DAQmx for CVI as starting point.

We must add the filling of the example tables. You can achieve that by the presence of a loop generting data and put it in the table.

By the way: because the material has a buffer on board, you can also write samples directly to the device, when available. The unit will display the samples in the order they were written on the device.

Best regards

Melanie Eisfeld

Personal sales engineer

National Instruments

Tags: NI Software

Similar Questions

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    See you soon
    Greg

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  • understand the buffer behavior

    Hello

    I'm developing an application with c ++ which uses a voltage of anaolg entry. I develop with a simulated device usb-6210.

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    Hi dan,.

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    I think the same thing would have happened on the fast computer, but it could take hours (4 times more memory), so I don't know about you.

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  • Visa series parallel read with arduinos, data are delayed

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  • Invalid pointer crash

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  • Why 'Read a fixed number of samples' help with the error 200279?

    Hello world

    It is a question about a tip found in the explanations on the acquisition of data error-200279. This explanation it is said: '... ". reading a fixed number of samples instead of all available samples can fix this... »

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    But if I read everything which is available, whenever I read the only way for the buffer fills would be that the time between two readings take more time than necessary fill the entire buffer.

    Or in other words to each reading I will read at least as many elements that it has been filled by writing since the last read, so the only way to fill the buffer would fill completely at once since the last reading.

    This should be a lot safer than reading a fixed amount, because in this case, I'd get a problem if I read it that fewer items than writing complete at the same time, regardless of the number of items that would be and no matter what the size of the size of the buffer that would be.

    What I understand here?

    Thanks and regards,

    Sebastian

    SBach wrote: this VI is a State Machine in queue, the reading part is made in the case of timeout and cases are used as initialization orders, stop and change the outside DAQ hardware.

    That I can't tell when these commands will trigger the time between two readings could not be set. If a strictly fixed amount of data could lead to a buffer to fill.

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  • continuous performance counter data

    Hi all

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    Allard

    Allard,

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    or

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  • external delay time on imaq camera

    Hi all

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    My problem is that I can not manage to externally trigger the example attached "He'S triggered Ring.vi" without getting a timeout error.

    I was acquire images on a Dalsa 1 M 60 camera for a year using finite buffers, externally triggered, but the method of triggering that worked for me this last year is now a failed due to timeout error. I can confirm that my old program acquisition still work and physical relaxation is therefore able to reach the camera very well (g. trigger is identical to what I'm trying with the ring buffer).

    The error number is "1074397150 occurred at extracted IMAQ buffer. I spent the time-out of frame, added structures from sequence flat to make sure that things happen in a correct order separate counter in a separate while loop and has recently launched a campaign of the evolution of the parameters in the hope of getting lucky (I kid, but I get this desperate) randomly. I realize that this is probably due to a fundamental lapse in understanding on my part and I would appreciate anyone who can set me straight.

    Joined the .vi

    See you soon,.

    A

    Hello

    I am pleased to learn that the ring of triggering HL works. It is promising because it proves that the issue doesn't lie not with the framegrabber. I noticed one thing that is the default value, number of buffers in the HL triggered ring example is 10, while the default value is 5 in the low level version. Have you tried to increase the number of buffers in the low level program, and it allows you to run successfully?

  • AI trigger and measure multi channels

    Hi all

    I have a simple problem (using USB-6259).

    can repeat the measurement trigger of AI and measure multi channels, but not both at the same time.

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    Hi Hassan,.

    If you use an analog trigger with several analog channels, you will need to use the APFI0 input as source of relaxation. See this KB: Why do I get error-200264 when running analog reference trigger? All you need to do is to connect your analog signal online 0 to APFI0 (Paperback 20 in your case) and set the source of relaxation at APFI0.

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    Best regards

    Peter

  • Buffer problem and cases of ring series

    Hi all

    I had an interesting problem and have a moment that is difficult to find a solution and thought a pair of fresh eyes can help!  I read data during the series using VISA.  That's going well.  I do this continuously and then adding in a string.  This string, I look for new lines and pull them out of the buffer series chain.  I have then look at the lines to see if they have the appropriate orders and, if so, analyze these commands to control a box structure.

    Now, here's the interesting part.  When I started, I wrote a vi to take in an arbitrary multiline string in and analyze data and sentences, and it works as expected, but when I do it with serial data direct and the ring, the case statement buffer does not.  Also, when I probe the parsed string that will control the case statement, it LOOKS right, but the case statement will not accept it.

    Any thoughts would be greatly appreciated, I'm quite confused as to what is happening here.  I have attached the 2 vi.

    Gurus?  Masters?

    Thank you!

    Jim S,.

    I see a few problems.  As previously validated you should use greater or equal? instead of superior?.  The biggest problem is that you have a string constant value '\n', but the constant itself is not configured for '-' code display mode.

  • IMAQ extracted buffer is suspended in an ongoing acquisition with PCIe-1429

    I acquire images of 500 x 500 pixels at 1000 FPS from a camera of the Basler A504k using a PCIe-1429 (LabView 8.6, x 64 Vista). The images are processed online, and all works - some time. From time to time the program and out of just to extract vi buffer never gets. No error is produced. I need to kill Labview and restart it to leave. I read http://forums.ni.com/t5/Machine-Vision/BUG-with-PCIe-1429-Cameralink-full-config-Basler-sprint-lines... and implementation of the proposed solution, but no luck. I followed the lost images and buffer number called and can't find any problems. My VI is attached. The images, go to a queue and treatment by another part of the program. Any help will be much appreciated.

    Thanks Vinod,

    Another thing is that the structure of your program looks a little broken. You are extracting tampons from the ring, put a reference to the image in your queue, and then going back and extract a different buffer. This means that your previous buffer is no longer checked and could be replaced, but your loop else may not have finished processing this image yet.

    While this should be causing your current problem, but I thought it is interesting to point out. I think I have two queues of the source images. One that contains free images and one that contains the populated images. You producer loop of who you've given here would consume the free queue, take in one of these images, and then place it in the populated queue. Your consumer loop would be remove from the populated queue, process the image, and then put the image in the free queue.

    Eric

  • PCI1424 - invalid buffer with the acquisition of memory on-board triggered

    Hello

    I need to capture 2 images in a very short interval using a PCI-1424 and a camera Kodak/Redlake. I have to use the amount of memory shipped to capture images. Using the example

    \National Instruments\CVI\samples\IMAQ\Ring\ring mem.prj on board, I added the following code in "int CVICALLBACK Ring"

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    Concerning

    Roland

    I've found a workaround. I use the function

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  • How to write the raw buffer grabber (table 2D) image to PC memory?

    Hello

    I use a library C++ and NIImaq to save table raw image 2D on PC.

    I have a PCI-1428 acquisition card.

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    Thank you

    Travis

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    Also, you can find more information on how to set up in the developer zone article below Acquisition ring (Versus the system of onboard memory section memory speak your specific question).

    DevZone: Ring Acquisition

    Hope that helps!

    See you soon,.

  • What is a ring of ring/tx rx in router?

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    above market.

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    is there anyone which is a rx ring (ring of tx)?

    Hello

    I would add a little more.

    As well as public and private swimming pools interface, Cisco IOS creates special buffer called rings control structures. Cisco IOS and controllers interface using these rings to control what pads are used to receive and transmit packets to the media. The rings themselves are made up of media-controller-specific elements that point to the individual package also buffers in memory of I/O.

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