RP2040 support

[glennswest]

Looking at RP2040, be nice to have this work there. I could do up to 8 channels for my gateway.
32 bit, and some have on board wifi.

[khoih-prog]

The obstacle for RP2040 and many other boards, using W5x00 Ethernet or WiFi (NINA, etc.), is the Ethernet/WiFi libraries are not designed to support Async yet.

Only some libraries, based on LwIP stack, are supporting now, such as

1. Teensy 4.1 QNEthernet
2. ESP32 WiFi and Ethernet (WT32_ETH01). This is the promising solution for you.
3. STM32 Ethernet using LAN8742A or LAN8720
4. Portenta_H7 Ethernet/WiFi

We certainly have to wait for someone to rewrite those libraries as I don't have enough time / knowledge to finish all of the tasks.
Any help will be much appreciated by all of us.

[khoih-prog]

RP2040W using CYW43439 WiFi, using arduino-pico core v2.5.0+ can be a candidate.

Will spend some time to look at it to see if ready / easy or not.

RP2040 using the same core and lwip-based Ethernet, such as W5x00, ENC28J60, could also be considered whenever this enhancement [Feature Request] Port these libraries lwIP_w5100, lwIP_w5500 and lwIP_enc28j60 from ESP8266 #775 done.