LAN9303 with ESP32-WROVER-IE HELP!!!

[ahmetbasli001]

We made a card design and I am sharing the schematic parts of the relevant circuits.
Our design is as follows;
We connected the "ESP32-WROVER-IE(M213EH2864UH3Q0)" module to the LAN9303I-ABZJ ethernet switch IC over the RMII line. While designing, we made the design by referring to the development card I gave in the link " https://docs.espressif.com/projects/esp ... t-kit.html "( We also provided this development kit). We had previously made a similar design using the same LAN9303I-Switch chip using STM32 instead of ESP32 and managed to run it without any problems. but we are having trouble with the version with ESP. Our problems are as follows.

When the card with ESP32 is energized and run, usually (90%) ESP and LAN9303I chip do not get connected and the RMII connection cannot be established, but the LAN9303I chip works because the devices connected to the other ethernet ports make packet traffic between themselves.

We made ten prototypes, nine of them have these errors, and one has only a power up problem. In other words, if a card of ours is haerbded with ESP32 and LAN9303I at boot, the RMII line does not break afterward..
Components in all cards were checked and measured one by one. They are all the same.

We could not find that the problem was caused by hardware or software. We would be very grateful if anyone could give an opinion on this matter.

[ESP_ondrej]

Hi @ahmetbasli001,

I am not sure if I fully understand to your problem.

usually (90%) ESP and LAN9303I chip do not get connected and the RMII connection cannot be established

Does it mean that the ESP starts properly and the LAN9303I is properly initialized via SMI? And the only thing which does not work is RMII data interface (i.e. you cannot sent or receive any data)?

if a card of ours is haerbded with ESP32 and LAN9303I at boot, the RMII line does not break afterward.

Could you please be more specific what do you mean by this statement?

Thanks
Ondrej