How to configure LAN8720 RMII Ethernet on STM32F407VET6?

[c0ncua109]

Hi,

I am trying to use grblHAL STM32F4xx with:

• STM32F407VET6
• LAN8720 PHY
• RMII interface
• STM32CubeIDE

I would like to enable Ethernet support and use networking features such as Telnet/WebUI.

I have some questions:

1. Which board configuration should I start from for STM32F407VET6?
2. How do I enable lwIP and Ethernet correctly?
3. How should LAN8720 PHY be configured?
4. Is there an example configuration for RMII + LAN8720?
5. Which files should be modified?
6. Is an external 50MHz clock required for REF_CLK?
7. Are there any example projects using LAN8720 with STM32F407?

Currently I can build the project, but Ethernet is not working yet.

Thanks!

[c0ncua109]

I already tried enabling Ethernet by changing:

#define ETHERNET_ENABLE 1

but the project fails to build.

../Src/enet.c:33:10: fatal error: lwip.h: No such file or directory
33 | #include "lwip.h"

[terjeio]

1. stm32f407vet6_dev_board.h - Ethernet is working for this board, with a DP83848 PHY
2. - 7. A driver is required for the LAN8720 PHY, not sure if one is provided by ST. The schematic for dev board mentioned above could be a pointer, perhaps also the schematic for the Nucleo F756ZG dev board which uses a LAN8742 PHY.

The reason it failed to build is likely that the project is not set up to include the necessary parts - the Debug F407 25MHz ETH build configuration is (for the DP83848 PHY).

[c0ncua109]

LAN8720 is basically a lower-cost variant of the LAN8742 and they are largely register-compatible for RMII operation.

What would be the correct way to build grblHAL using the existing LAN8742 Ethernet configuration?

Should I just use the existing Debug F407 25MHz ETH build configuration and keep the same PHY driver setup, only changing the PHY address if required?

My hardware is STM32F407VET6 + LAN8720 in RMII mode.

[terjeio]

You have to get (or write) a LAN8720 driver and create a build configuration using it. Copy this and change the two last include paths:

Perhaps the F7 LAN8742 can be used as-is or as a base if no driver is available for the F4. To check if a driver is available previously I added a new project and edited the .ioc file - but the latest IDE version tell me to install stm32cubeMX to do so, which I have not done yet.