ISSUE WITH DSI MIPI ADAPTIVE COMMAND MODE HP TRANSMISSION

[JP.4]

I am currently working with the STM32U5G9J-DK1 development kit interfacing with a Tianma-based display. I have successfully managed to update the display using adaptive command mode with DSI long and short write commands. However, I am encountering issues related to the refresh rate and switching modes:

1. Issue with Refresh Rate:

• While updating the display using long write DSI commands, I observed that the refresh rate is significantly slow. To optimize this, I attempted to change to High-Performance (HP) mode after the initialization commands.

1. Problem Switching to High-Performance Mode:

• After the initialization commands and sending a pixel memory write command, I disabled the DSI long write command from low power to check if the display would operate in HP mode.
• However, when I disable the low power (LP) mode for long write commands, the display shows nothing. The display only works if I enable LP mode for the long write.

1. Configuration Details:

• I am using FIFO while writing pixels in long write mode.
• I have confirmed that the initialization sequence and command settings are correct, as they work in LP mode.
• The issue arises when attempting to transition from LP mode to HP mode.

Request for Assistance:

Could you provide guidance on:

• Why the display does not work in HP mode after disabling LP mode for long write commands?
• Are any additional settings or configurations required to enable proper HP mode operation?

Your assistance in resolving this issue would be greatly appreciated.

Thank you.

Best Regards,

JAYA PRAKASH P

EMBEDDED MODULE LEAD

EMAIL: jayaprakash_p@aktisengineering .com

[KDJEM.1]

Hello @JP.4 ,

 

What do you mean by High-Performance (HP) mode? Do you mean High-speed mode?

For more information about REFRESH Rate and High speed mode, I recommend you to take a look at AN4860: Introduction to DSI host on STM32 MCUs and MPUs 

Could you please share you project?

 

Thank you.

Kaouthar

 

[JP.4]

HELLO KDJEM.1

                           

Thank you for the clarification and your assistance with my question. Your input has been constructive, and I appreciate your support. Still, we are working on it once we reach some level we will share the project for more review...

Best regards,

JAYAPRAKASH P

AKTIS ENGINEERING SOLUTION PVT LMT

[David George]

Hi JP.4 - did you ever get a fix for your DSI problem? I have exactly the same issue myself - works in LP mode, but not in HS mode.

I scoped the line data in HS mode and the data output is actually different from that I expect, it often misses off the first byte (the ID byte from the Header).