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I am testing the Digital Trigger with DAQ device

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When running an waveform measurement task using digital trigger to acquire Finite Samples with DAQ device, I receive the following error.

 

Read: Error -200278: Attempted to read a sample beyond the final sample acquired. The acquisition has stopped, therefore the sample specified by the combination of position and offset will never be available. Specify a position and offset which selects a sample up to, but not beyond, the final sample acquired. The final sample acquired can be determined by querying the total samples acquired after an acquisition has stopped.

 

Below is block diagram. I gave 5V DC to the PFI0 pin as a trigger. How can it be resolved? 

20220321_214757.png

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Very much guesswork here.  Sounds to me like the task didn't see the trigger, so the finite task never even started acquiring data.  Thus the attempt to read the whole buffer failed because you were requesting data that hadn't yet been acquired.

 

One tip in case you didn't know: triggers need to be digital *transitions*, not digital states.  To see your PFI0 5V signal as a trigger, you need to start your task while PFI0 is at 0V, then *transition* PFI0 to 5V.  That will trigger your task.

    If PFI0 is already at 5V when you start the task, it'll never see a transition and never start acquiring.

 

 

-Kevin P

CAUTION! New LabVIEW adopters -- it's too late for me, but you *can* save yourself. The new subscription policy for LabVIEW puts NI's hand in your wallet for the rest of your working life. Are you sure you're *that* dedicated to LabVIEW? (Summary of my reasons in this post, part of a voluminous thread of mostly complaints starting here).
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I appreciate your quick reply and also advice for my future career, sir!

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Accepted by topic author Medschool

I'm going to be modifying my signature.

A. It implies a little more than I *really* mean

B. NI may make a change that would help

 

As things stand now, my actual advice would be more nuanced but follows these thoughts:

1. LabVIEW will be around a while

2. Higher continuous costs would make it more of a specialist's game

3. It can take a while to figure out whether you want to be one of those specialists, and cost quite a lot along the way.  It's far from obvious that it'll be a worthwhile tradeoff for the majority of occasional users, many of whom *won't* get to the point of "thinking in LabVIEW" naturally.  So I wouldn't steer someone toward it.  (I also wouldn't pull someone away that shows both the knack and the interest.)

 

But keep listening, just in case some changes come from NI.

 

 

-Kevin P

CAUTION! New LabVIEW adopters -- it's too late for me, but you *can* save yourself. The new subscription policy for LabVIEW puts NI's hand in your wallet for the rest of your working life. Are you sure you're *that* dedicated to LabVIEW? (Summary of my reasons in this post, part of a voluminous thread of mostly complaints starting here).
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