ESP32-P4: Internal Ethernet MAC vs external SPI Ethernet controller

[danielm]

What are pros/cons of using internal Ethernet MAC vs external SPI Ethernet controller (e.g. W5500) in case of ESP32-P4?
Obvious difference is in pin count needed on ESP32-P4. Price difference of external PHY (~ 1 USD) and external controller with PHY (~2 USD) is not significant for most of the applications. What about other aspects? RAM usage, CPU utilisation, etc.?

[ESP_ondrej]

The SPI Ethernet is much slower. You can achieve more than 90 mbps for Tx/Rx UDP with internal EMAC. With SPI Ethernet is around 17 mbps.

[danielm]

Thanks for your reply, good to know. Anyway for applications where Ethernet is used for MQTT telemetry and occasional firmware download reduced throughput is not an issue. Do you see any other disadvantage of SPI-based controller approach?

[DrMickeyLauer]

I've used the W5500 in some projects. It's a stable workhorse, but it requires quite some support circuitry and it lacks MDI-X.

[danielm]

Could you please elaborate more on support circuitry? It basically needs crystal oscillator circuit and several capacitors. Similar components are required for IP101GRI PHY which is used with internal EMAC of the P4 evalboard. Am I missing something?