eye diagram

[muhsen]

I have HP 54120A, and Tektronix TDS 210 oscilloscopes. I have downloaded the

Labview driver and they working perfect. My problem is I can’t read the eye diagram on the labview even it is displayed on the oscilloscope screen, the only thing I can see on the labview is a different signal. I have tried to change and modify my diagram but I failed to get the eye diagram on the labview.

Kindly, i'm asking for help to get the eye diagram displayed on the labview

Cheers
muhsen

[mfitzsimons]

Eye Diagrams are created using persistance mode.  That is, the same screen is redrawn many times without clearing the previous data.  You may have to use an XY plot and not clear the data between samples.  My guess is you are seeing the individual samples and not ALL of the data.

Matt

Message Edited by mfitzsimons on 05-08-2006 07:02 AM

[altenbach]

Easiest would be to implement this using either an intensity graph or a picture indicator. Just keep a 2D array in memory and increment pixels as the traces accumulate. Long ago, I made a simple example.

Have a look at my demo VI (MemoryGraph03.vi, LabVIEW 7.0) discussed at the end of this earlier thread.

NOTE: I just noticed that something is messed up with the Z-colors when opened in LabVIEW 8.0 (All traces remain white!). If you use LabVIEW 8.0, you might need a tweak or two to get it working properly.

Message Edited by altenbach on 05-08-2006 07:45 AM

[mfitzsimons]

Cool graph but a poor looking Eye Diagram

[altenbach]

Fix for LabVIEW 8.0 in my example above:

• You must change the number for the white marker from 256 to 255 in the diagram constant in the upper left of the diagram (feeding to the Zscale.MarkerVals[] property node). Apparenty LabVIEW 8.0 chokes if the marker is outside the valid range of the datatye (U8).

See attached (LabVIEW 8.0). Good luck! 🙂

[muhsen]

Thank you very much for you help.
the MemoryGraph03.vi, looks cool, , but i have tried to link it to my file, it didnt work .
could you please ehlp me to find a way to link it to my labview driver.
the driver is attached.
thanks for your help