Pattern generation data interleaved with Z values

[Roche]

Hi,

I configured a simple clock output in WaveForms v3.21.3. The clock frequency is 1MHz and the output type is PP. Hovering the mouse over the generated graph, I notice every now and then that the value is Z, instead of 0 or 1. Looking at the pattern in the export window, I can see that every 4th value in the pattern shows Z. Is this just a tool artifact, or is the output actually being set to high impedance every so often?

Thanks,

[attila]

Hi @Roche

Yes, Z stands for high impedance

[Roche]

Hi attila,

Thanks for the quick reply. What I find strange is that the pattern generator is inserting Z values in the pattern. I created the attached examples to reproduce it. I am using simple clock patterns of 1MHz, and I observe the following:

• Configuring DIOs 24 through 31, inserts Z values in all signals
• Configuring DIOs 24 through 32, inserts Z values in all signals, except on DIO24 and DIO32.
• Configuring DIOs 24 through 33, inserts Z values in all signals, except on DIO24, DIO25, DIO32 and DIO33.

For some reason, adding more DIOs fixes the inserted Z issue on the lower DIOs. You may be able to see it in the attachements when hovering through the signals or opening the export dialog, as shown in my original post.

I am curious if this is just an artifact of how the patterns are displayed/presented, or if the DIO is actually switching to Z instead of 0 or 1 during the transmission.

Thanks,

 

DIOs_24_thru_31.dwf3work DIOs_24_thru_32.dwf3work DIOs_24_thru_33.dwf3work

[attila]

Hi @Roche

I don't understand where you see Z.

Here 24 is PP drives low/high, 25 OD low/Z, 26 OS Z/high, 27 TS low/high/Z
The uncontrolled DIOs (neither from StaticIO, Patterns, Protocol...) are by default in high impedance.
The Patterns preview is just a preview, with high zoom out or certain situations it may not show the signals correctly.

[Roche]

Hi @attila,

On that screen, simply click on File->Export, and you should see the the Z's interleaved with the data. At least on version 3.21.3:

[attila]

Hi @Roche

Thank you for the observation.
Corrected for the next version.

[attila]

Hi @Roche