TPS65982D Related questions

David,

Can you draw a simple diagram showing the connection of the systems and where the DUT is in the system setup?
DUT = Notebook, Dongle = Apple A-B-Y Dongle for power+Video(HDMI or VGA?)+USB, Monitor = Make/Model?

You said "Apple Dock" but I'm not familiar with this product. Can you send me link to product page?

What does "Computer-Only Mode" mean? What does "Duplicate Mode" mean?

From just looking at the waveform, it looks like multiple plugs/un-plugs are happening (either physical or simulated) and the PD traffic is repeating over and over again.

Are you forcing HPD signal with a waveform generator? I do not see any USB PD traffic on the CC line when the HPD signal toggles, so HPD does not seem to be related to your problem.

Hi Brian

Block and apple dock link as below.

world.tmall.com/.../525945488112.htm

 "Computer-Only Mode"  means just notebook display, monitor doesnt display. "Duplicate Mode"  means monitor duplicate what notebook displays.

You mean HPD signal change is not caused by the repeated PD traffic?

Test condition is that: connect as the above block shows and keeo the cable attached always, set to  "Computer-Only Mode" , but several seconds later, it switch to duplicate mode. HPD and CC test waveform as last post shows.

Regards

David

Hi Brian
i think that HPD signal is caused by repeated PD traffic. what is your comment here?
Regards
David

Hi David,

HPD_IRQ will let the DFP_D (DisplayPort Source) that there was some sort of change on the UFP_D side (DisplayPort Sink). A change can be something as a resolution change or a extend screen. This will be done through the AUX channels in DisplayPort. Basically you have the Dongle's display chip and the graphics on the notebook talking directly. The best way to see what is being sent between the notebook and the dongle is with an AUX analyzer. It would be tedious to look through the data but you can check for repeated messages that are not responded to. From my experience the duplicate screen is a default for most graphics on notebooks. When you are in the duplicate mode are you able to adjust the screen resolution?

Jacob

Hi Jacob,

Thanks for your quick response!

In fact, we tend to set it to computer only mode. It will switch to dumplicate mode automaticly. This is the issue. What do you mean by saying "When you are in the duplicate mode are you able to adjust the screen resolution?"?

regards
david

Hi David,

When you go to graphicsleep properties are you able to adjust the screen resolution?

Jacob