SN65DSI84: Show occasional snowflakes

Hi,

I would follow the debugging steps in the following e2e FAQ as the first step, https://e2e.ti.com/support/interface-group/interface/f/interface-forum/990480/faq-sn65dsi84-how-to-debug-flickering-video-with-sn65dsi83-sn65dsi84-and-sn65dsi85.

Thanks

David 

Dear David

The customer debugged SN65DSI84ZXHR according to the steps of E2E, but the customer's defect was not improved.

Snowflakes only appear when the desktop is refreshed.

DSI input LVDS output was measured, but no difference was found. The problem of snowflakes was determined, which has nothing to do with timing at present.

This is schemetic:

PCB Layout:

Hi,

So if I understand correctly, there is no snowflakes when the board powers up initially, and the problem only shows up after refreshes?

When refreshes, are you changing to a different resolution? 

What happens to the DSI input when refresh happens?

Does the snowflakes go away after certain amount of time?

Does the DSI84 status registers reported any error after being cleared first?

Thanks
David 

Dear David

As customer said:

1. Only refresh will appear

2. No change in resolution

3. No change in DSI

4, will not disappear

5. No error was reported

Hi,

After refresh, if you reset and reprogram the DSI84, does the snowflake go away?

Thanks

David 

Do you mean to reload the driver of dsi84 ?

From the perspective of the line, you can't reset，Or please provide a way to reset

Hi,

I am trying to understand what is involved with the DSI84 when there is a refresh? And as a experiment, if you reprogram the DSI84, does the snowflake go away?

Thanks
David

HI

1、I know what you mean，But I need to know how to reset the reset method you said，Please tell me the reset method

2、In terms of hardware, if there is no pin that can be reset, how can the software reset