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Southbranch
Senior
December 11, 2022
Question

Fail to configure ETH + LTDC 24bit for STM32H725ZG in CubeMX

  • December 11, 2022
  • 4 replies
  • 1554 views

Hi!

The STM32H725ZG comes in a 144-pin package and configuring ETH RMII + LTDC 24 bits (RGB888) in parallel would seem realistic. But I have failed even though I have tried to move around pin configurations quite a bit.

A single pin (PA2) seems to be the issue.

Thanks for any hints in case I missed something.

This topic has been closed for replies.

4 replies

ST Technical Moderator
December 12, 2022

Hello @Lars Sörqvist​,

It would be better to share your configuration, this will help Community user to understand your issue.

Check the LTDC initialization, ETH clock...

Review this article, it may help you: How-to-create-project-for-STM32H7-with-Ethernet-and-LwIP-stack-working

Check the board User Manual, maybe you have a physical connection issue.

Imen

In order to give better visibility on the answered topics, please click on 'Best answer' on the reply which solved your issue or answered your question. Thanks
Southbranch
Senior
December 12, 2022

Thanks Imen,

But so far it is a straightforward issue about pin configuration only, i.e. no user code or LwIP involved.

These are my steps:

  1. I started STM32CubeMX with a new project from scratch for the MPU STM32H725ZG.
  2. I then trried to configure ETH RMII + LTDC RGB88 respectively
  3. There where pin conflicts (no other features/pins configurated)
  4. I tried to move pins around in STM32CubeMX but still ended upp with conflicts

I was just hoping to get an extra pair of eyes on this in case I missed some pin swapping, thats all.

Kind regards

Piranha
Principal III
December 13, 2022

Consider using LTDC in 18-bit mode. Take a note that most LCD panels are 18-bit anyway, even those with 24-bit interface.

Southbranch
Senior
December 13, 2022

Thanks, yes that it possible.

However, I have a specific 24-bit screen in mind but I assume I would need to move up to a chip with more pins then?