Ethernet configuration on STM32F746G-Disco

[hbZhao]

Hello, I have one STM32F746G-Disco, which works well with TouchGFX (v4.22.1) and STM32CUBEIDE (v1.13.2).

However, when I enabled the ethernet and LwIP, then set the PHY to LAN8742 in the LwIP, the display does not work as below. If I did not set the PHY, the display was shown well.

After debugging, the application is stuck in the function of low_level_init in the file ethernetif.c.It keeps checking the link statue after pressing F8 to resume the application in the debug mode by STM32CubeIDE. Although the state is LAN8742_STATUS_100MBITS_FULLDUPLEX (2) which is bigger than LAN8742_STATUS_LINK_DOWN (1).

And at the same time, if disconnecting the ethernet cable, the PHYLinkState does not changed.

May I know if there is anything I should set? Thanks.

[hbZhao]

[Deleted]

[jiangfan]

You may do stepping to see what the source is causing bad display. My feeling is that some ethernet operations may change STM32 LTDC clock - hence LCD display is bad.

[hbZhao]

When debugging the source codes, the application keeps in the loop to check the status in the line "PHYLinkState = LAN8742_GetLinkState(&LAN8742);". Although the PHYLinkState is 2, the application cannot run to the MAC configuration.

And I wonder whether ST can generate working codes properly. More ridiculously, there is not working example generated by CubeMX or CubeIDE rather than SW4STM32 in the repo package.

[Piranha · Accepted solution]

Well, the feeling is completely wrong. For Ethernet the RMII 50 MHz clock is external, the AHB doesn't need a specific frequency and the only clock the software configures, is the divider for MDIO interface, which is not related to the LCD.

https://community.st.com/t5/stm32-mcus-embedded-software/how-to-make-ethernet-and-lwip-working-on-stm32/m-p/261456

[hbZhao]

Hello @Piranha ,

Thanks for your feedback. I have read the posts in your link. But no posts can help in this case.

I have spent so much time on this case. So many issues are still open without any solutions.

IT IS SO DISAPPOINT THE STM32CUBEIDE/STM32CUBEMX DO NOT WORK ON STM32F746G-DISCO, EVEN ALL OF THEM ARE FROM ST.

IT SHOULD BE BETTER TO QUIT FROM ST MCU IN CASE OF FURTHER ISSUES.

[Piranha]

I have read the posts in your link. But no posts can help in this case.

Is this some reality denying religion? Fix the code and it will work - as simple as that.

IT SHOULD BE BETTER TO QUIT FROM ST MCU IN CASE OF FURTHER ISSUES.

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The hardware is fine. Instead of using a broken bloatware, write and use a decent code and you will get great results.