Transition measurement vi cursors displayed in waveform graph are moving outside of scale

[debugg]

Using a waveform graph to display pressure over time. I wanted to be able to calculate the fall time of the pressure over time so I'm using the Transition Measurement vi. I copied exactly what was in the example for transition measurement inside help and it is correctly determining the falling transition time but I am having a problem with the cursors on the waveform graph. I should be seeing a set of green vertical cursors marking out the fall start time and fall end time like in the picture I've attached (capture2) like in the example. The problem is they both always start at 3.43 (capture1) and after each sample period they increment by one (4.34, 5.34, 6.34) The come right out of the bundle from the transition measurement output as those numbers. The period of the signal I'm interested in is always less than 2 seconds, so I never see the vertical cursors.

I've tried substituting my daq signal with a sine wave generator and it does the same thing.

The block diagram is in the first capture

also I would be interested in finding out exactly how the numbers wired to the active cursor property of the property node for a waveform graph relate back to the actual cursors on the graph. Are they just automatically numbered starting with 0 from the top-down?

Wayland

[J-Barticus · Accepted solution]

Hi Wayland,

The reason the cursors are always apparent in the example VI for the Transition Measurement.vi, is because the signal being generated is always resetting. So, the signal resets to a 'new' signal for the cursors to go over and therefore always remain in the somewhat same location. The Waveform Graph is also configured in such a way that it will not move or continue to show new data coming in, the data cursors have moved onto. So in your case, you will want to right click the graph and make sure "Ignore Time Stamp" is not checked/selected. This will make it so the graph keeps up with your incoming data and the cursors. You can check this in the example file by removing the True Constant going to the waveform generator and changing the time stamp option previously mentioned.

In order to view the available cursors and their numbered position, you can right click on the Waveform Graph and select properties. In the properties window there is a Cursors tab, inside this tab at the top is a drop down menu that lists all of available cursors, indexed starting with 0 at the top.

-Jake B.

[debugg]

ahh, I see now. That took care of it. Thanks for your help