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Capture on trigger fast into array. Create curve for user slower appart from Data acuisition.


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Hello everyone i am relative new to labview and currently i am bit stuck need help...

i want to capture data with a digital trigger on my chassis PFI0 (9178), the pulse is 20ms long and occurs on my straingauge 9237 module.

The pulse comes in 10 times in a row with couple of miliseconds between it, can i measure it every time and push it inside an array like a "last in first out" memmory to evaluate it slower for the user?


I am currently struggeling with the loop dividing into more then one loop approach.



How to breach out from accquire->store->plot in one loopdone right with good performance? I don't know how to shape the cure because there is a dependency from loop time to datapoints with the daqmx task inside of it :-/

Capturing should always be possible and run in background and the user just uses the frontend to play around with filters (me learning what filter shape the cure in which way)


It would be nice if someone can share their knowledge towards realizing multiple graphs from a pulse that comes in and is stored in a graph.

I know my program is not pretty right now but with progress it will be nicer, function first to learn!



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I don't fully understand what you're wanting to do, but as a starting point it sounds like you want to use the producer-consumer pattern where the daqmx code is a continuously-running data producer and your UI is a data consumer. They communicate using a queue (eg a first in first out buffer, as you suggest). There are sample projects included in labview (eg "continuous measurement and logging" here http://www.ni.com/product-documentation/14031/en/) which may give you a better starting point than a blank diagram.

It also sounds like you may need some assistance with how to trigger and fetch your data -- it sounds like you need something like this (https://forums.ni.com/t5/Example-Programs/Finite-Acquisition-with-a-Software-Retriggerable-Reference/ta-p/3530011) but you might also read through this: http://www.ni.com/tutorial/4329/en/

Also, depending on how much you want to do or how far you want to go, it may be worth the money to just buy an application like FlexLogger: https://youtu.be/hoNoJjMsuGI You can download a demo and see if it does what you want http://www.ni.com/en-us/shop/data-acquisition-and-control/flexlogger.html

Edited by smithd
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