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Transition not showing on LabVIEW Digital Waveform Graph when using Tektronix instrument driver

Hi all,
I'm programming a Tektronix MDO4104-6 oscilloscope via USB with the newest update (5.0.1) of the Tektronix DPO MSO 2000 4000 Series instrument driver (http://sine.ni.com/apps/utf8/niid_web_display.download_page?p_id_guid=6E23DB10D9FC2B05E04400144FB7D2...).
I'm using LabVIEW 2011. The first 4 digital logic lines of my scope are connected to an interface that is giving off random digital signals.
I run the example program Tektronix DPO MSO 2000 4000 Series Acquire Multiple Digital Waveforms Example.vi. I've attached the resulting image, "example screenshot". The digital waveform shows the states of the 4 digital lines, line 1 (the red one) transitions from 1 to 0. Yet there is no vertical line to denote the changed state. To see what I mean, take a look at the screenshot created from the attached dig sim VI.vi. Every transition has a vertical line showing the transition.
I wanted to get a wider horizontal timebase and remove the autosetup to better see the signals so I copied the same Digital Waveform Graph from the Example over to a new VI and created the attached "digital working VI.vi". I've also attached the screenshot after running that VI and it shows that several transitions occur but there is no vertical line denoting the transitions. I can also clearly see the transitions on the display of the Tek scope.
I've played around with the Plot Legend, checked the underlying code, compressed and uncompressed the signal, and created property nodes galore from the different instances of the Digital Waveform Graph to determine what's being changed by the signal coming from the Read VI in the driver, but I thought it would just be easier to ask someone. 
Anybody have an idea what's happening? Am I just missing something obvious? It happens...
Thanks!
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Attached are the VIs I mentioned in the post.

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Message 2 of 14
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Hi,

 

Just to double-check, have you tried to just copy and paste the "correct" digital waveform graph into the other VI and use it so both would be showing the correct vertical lines in the graphs? I can't simulate the hardware but another good step would be to double check the properties of the X-axis display formatting on the graph you are having trouble.

 

Right click on the digital waveform graph on the front panel > go to Display Format tab > at the bottom, select "Advanced editing mode" > make sure your other graphs have the same formating your "correct" graph which is currently set with:
 

displayformat.png

 

Let me know if you have questions. I hope this helps!

 

 

Aldo A
Applications Engineer
National Instruments
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Hi Aldo,

Yes, I have copied the graphs back and forth a few times. I checked the properties in the dialog boxes and also the properties by comparing the property nodes.

 

Any other ideas why this may be happening?

 

Brian

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Hi Brian,

 

Assuming that you have the same properties on both graphs and it still doesn't show correctly, how about you create another copy of dig sim vi and just add the channels and visa resource controls?

 

 

Aldo A
Applications Engineer
National Instruments
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Hi Aldo,

Yes, I did that when I copied the graphs back and forth between the examples from the driver and the dim sim VI I made. It doesn't work, the transitions still don't show up. I'm assuming there is something in the underlying code coming from the Tektronix driver that is changing the digital waveform and thus the graph.

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Hi Brian,

 

I'm going to try this out on a 4000 series and look into what might be causing it. I appreciate your patience. Thanks!

 

 

Aldo A
Applications Engineer
National Instruments
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Hi Aldo,

Thank you very much for your help, I appreciate it!

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Hi Brian,

 

Have you tried running a new instance of the instrument driver for the 4000 series Tektronix? Let me know if you have already tried this. 

 

 

Aldo A
Applications Engineer
National Instruments
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Message 9 of 14
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What do you mean by "new instance"? I've opened and closed LabVIEW several times, unplugged and replugged in the scope, and basically restarted everything over the course of a couple weeks. No change. I'm also using the very latest version of the instrument driver.

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