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cursor triggering waveform

Hi everyone,

I'm trying to do a triggering of a waveform with two cursor one for start and other for finish , so if i get the position of the two cursors ,i want to get a subset of the first graph in another graph ,any idea of how i could do that please ? 

i've joined a picture of what i want to do .

Best regards,

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Message 1 of 22
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Keep the two indices in a shift register and  use "cursor release" events to update the cursor position ("cursor index" from property nodes or "PointIdx" from the event data node), followed by taking a subset for the second graph (sort the indices first). Make sure the cursors are locked to the plot.

Message 2 of 22
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This old example (posted here) should get you started. Just graph the subset instead of taking the mean. Easily expandable for even more cursors.

Message 3 of 22
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Thanks for your reply i'm trying to do the same and instead of the mean i do a graph . but i have a problem how can i get the of block of waveform to get the active cursor and cursor index i don't have the same in property node of my graph .

please find attached my Vi

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Message 4 of 22
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First of all, the cursors need to be locked to a plot (instead of free dragging). All the properties are right there, you just need to select them in the right order. You also probably want to have a small wait inside that loop.

Simply create a property node that has the items as in my example. Make that "active cursor "write" mode, and the rest "read" mode. To get the cursor index, you need to go right from the cursor into a new submenu.

Message 5 of 22
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sorry but what do you mean by the cursors qhould be locked to a plot ,and in which part of my diagram ?

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Message 6 of 22
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Hi nasnas,

 

what about reading the LabVIEW help?

Best regards,
GerdW


using LV2016/2019/2021 on Win10/11+cRIO, TestStand2016/2019
Message 7 of 22
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Thanks GerdW ,now i understand the difference

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Message 8 of 22
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I have a question about the cursors : i'm wondering if it's the same as triggering (like in an oscilloscope apply some impulsion to my signal at a certain threshold) 

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Message 9 of 22
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Hi nasnas,

 

I have a question about the cursors : i'm wondering if it's the same as triggering

A cursor is no trigger…

Best regards,
GerdW


using LV2016/2019/2021 on Win10/11+cRIO, TestStand2016/2019
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Message 10 of 22
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