Responding to a field Digital Input immediatle​y..

In a code for a a test rig ( LV7.1 + Win XP ) I am scanning all digital
inputs once every 50ms inside a timed loop. But there is one input from
a proximity switch that I need to be able to respond to immediatley as
it changes state.
 Any delay  of even a few ms, will add on to the reversal error of a servo drive motor.
 Ideally what I am looking for is a kind off  Interrupt
or  Event Structure for an external field input.  I know this
is not there in LV, but would be ineterested in achieving the same
functionality by some other means.
Thanks
Raghunathan
Raghunathan
LV2012 to Automate Hydraulic Test rigs.

Hello Raghunathan,
It LabVIEW if you are polling your device every 50ms for data, you will only get updates from your device every 50ms. It sounds like you are looking for some sort of change notification or change detection from your board. It is likely that you will get a much better and faster response to this question on the Multifunction DAQ or Digital I/O discussion forums since this is primarily a hardware question. If you decide to post to the hardware discussion boards, it may also be a good idea to list the specific hardware you are using so that people with similar setups can share their experience.
Best of luck,
Chris J
Multifunction DAQ board
http://forums.ni.com/ni/board?board.id=250
Digital I/O board
http://forums.ni.com/ni/board?board.id=70

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    -Dave
    [email protected]

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    Attachments:
    Read Dig Port.vi ‏51 KB

  • How can i connect 24VDC to digital input (usb 6008)

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    There are only two ways to tell somebody thanks: Kudos and Marked Solutions
    Unofficial Forum Rules and Guidelines

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  • How to I connect Sourcing digital output from My Interface Board to NI USB 6501 channel configured as Digital input

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    There are only two ways to tell somebody thanks: Kudos and Marked Solutions
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  • I was given an assingment, but have no idea where to begin. The assingment is to create a text file using notepad with all of my digital inputs and some how make those imputs show up on my digital indicators on my control pannel

    I was given an assingment, but have no idea where to begin. The assingment is to create a text file using notepad with all of my digital inputs and some how make those imputs show up on my digital indicators on my control pannel.
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    StevenD: FYI, I did NOT give you the one star rating. I would never do that!
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    Ow. Someone is grumpy today.
    Well, this is an assignment, so it is probably homework.
    Why else would anyone give HIM such an assigment, after all he has no LabVIEW experience and the tutorials are too hard for him?
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    Message Edited by altenbach on 06-24-2008 11:23 AM
    LabVIEW Champion . Do more with less code and in less time .

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    *** Say 'Thanks' with Kudos ***

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