Timed loop works not well

Hi,
how can I get a digital signal shorter than 25 microseconds? I am using
a RT-system, and I am using a timed loop with the internal clock, but I
can't get it faster than 25 microsecs.
Thanks
Tim

Tim,
Sorry I don't know much about RT but you may find a better response to your questions if you post in the real time forum.
http://forums.ni.com/ni/board?board.id=280
Brian

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  • Does two timed loop work together? is it possible....

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    Attachments:
    RT TEK.vi ‏105 KB

    Two loops in parallell is quite easy, you just need two unconnected loops. If there's a wire in between you get data dependency which means the 2nd loop will wait until the 1st one finishes.
    Is that what happening to you? (I cant open the file)
    /Y
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  • Timed Loop timing source - Control Loop From Task is too slow

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    You're welcome!
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    NI Services
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  • Timed loop

    Hi all ! I have a question ...
    I have a timed loop (which run on RT target ) . I  parameter this loop with  1Khz clock and 1 ms period. The aim of my program is to transmitt/send CAN frames. When i parameter my programm to send a frame every 10s, I receive my frames after 9993 - 9994ms ! I also tested my program with 1 Mhz clock and 1000 µs and i still have the same problem.
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  • What is wrong with this (timed loop error)?

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    Attachments:
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  • Controlling processor on the timed loop

    Controlling attributes of a Timed Loop does not seem very straight forward to me! I experience crashing my VI very often when my Timed Loops are featured with controlled period and sometimes processor and offset on their next iterations. Of course there are queues between the Timed Loops, too. Not yet sure of the cause of the frequent crash!

    Hi Siamak,
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  • Timing Loop won't Execute

    I think this is a labVIEW bug, but I'm looking for a work around or a 'gotcha'.
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    eximo
    UofL Bioengineering M.S.
    Neuronetrix
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    Attachments:
    timing loop.PNG ‏9 KB

    The attached image of the first post is the disfunctional version, Attached to this is a segment of the VI with the example disfuctional timing loop at the bottom right.  
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    eximo
    UofL Bioengineering M.S.
    Neuronetrix
    "I had rather be right than be president" -Henry Clay
    Attachments:
    Timing loop not working.PNG ‏68 KB

  • Timed loop not starting - works after closing and opening project

    Refer the image below - a simple timed loop should run when the Run button is pressed. What happens is that the parallel vi runs (see arrow) but the vi inside the loop doesn't.  Both vi's shown run forever (i.e. the timed loop is only used to specify the CPU).  
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  • Timed loop in LabVIEW DLL does not exit nicely

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    LabVIEWTimedLoopDoesntExit.png ‏103 KB

    Update:  I tried the simplest possible "While" loop and it works.  If I replace it with the simplest possible Timed Loop, it doesn't.  (See attachments.) 
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    Attachments:
    Doesnotwork.png ‏43 KB
    DoesWork.png ‏9 KB

  • Why does a CRIO-9004 only provide a timed loop of 1kHz (clock) and not 1MHz?

    I essentially have a compact CRIO-9004 and require a PID loop with update rates around 4-5 kHz. Additionally, I was hoping to use multiple 'timed loops' in the program in order to synchronize certain events. During this coding, the timed while loop will not work with a 1MHz clock rate and I am stuck with a clock rate of 1kHz instead. NI claims that PID loops in conjunction with the CRIO may have up date rates as high as 200 ksps. However, it appears that by employing the 1kHz clock that I can only obtain 1 ksps.
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    John-
    The 9215 has a conversion time of 4.4us when scanning 1 channel (see page 14 of the 9215 operating manual).  This equates to a little over 227KS/s.  The 100KHz value is if you are reading from all 4 channels.
    Link to operating manual:
    http://digital.ni.com/manuals.nsf/websearch/5F2E96​40C1CFE645862573AF007ABAD9
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    Message Edited by Support on 10-16-2009 09:16 AM

  • Timed loop inside a flat sequence not terminatin​g

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    I am a new user for LabVIEW. And I met a problem which really frastre me!!! Hope someone can help me out. Thanks in advance!
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