W55RP20 Support Requirements

[min-hs]

Our engineers have made initial progress in developing a driver for the W55RP20, but we've encountered a few difficulties that we would like to address with your team. Below is a brief overview of the situation:

The W55RP20 is a SiP project that integrates the RP2040 and W5500 in one chip. Internally, the dies are connected via general GPIO pins, not the typical SPI pins. As a result, a PIO program is needed to configure these pins for SPI communication.

Our engineers then decided to start from scratch, writing a PIO program and general code to initialize the W5500 through registers. They were able to create a basic loopback server in standalone mode. While this solution works as an alternative, we thought about the possibility of creating a new CHIP_VARIANT for rp2 CHIP_FAMILY. Given our limited resources, we thought of collaboration with Adafruit to further develop the driver.

The link below is to a WIZNet PIO example we created.
https://github.com/WIZnet-ioNIC/WIZnet-ioNIC-Circuitpython

[dhalbert]

There are PIO SPI examples here: https://github.com/raspberrypi/pico-examples/tree/master/spi, but it seems like you are well along in your PIO SPI implementation.

I'm guessing that you had to choose the pins you did due to limitations of the placement of the bonding wires between the chips. Is that correct?

While this solution works as an alternative, we thought about the possibility of creating a new CHIP_VARIANT for rp2 CHIP_FAMILY.

I am not sure what you mean by this. The PIO SPI could be separated out, and then the W5500 functionality could be done mostly in a library and in device-independent code. For instance, see https://github.com/adafruit/Adafruit_CircuitPython_Wiznet5k

[min-hs]

Yes, that's right.
We are currently using PIO SPI due to wiring issues between the RP2040 and W5500.

I've currently made some similar to wiznet5k to control the W5500 with PIO SPI instead of busio.SPI, but I'm having trouble getting it to work with different socketpools, dhcp, dns, and other protocols.

Also, if I do this, I would like to discuss with you how to utilize the W55RP20 library from adafruit to make it available to users in the future.
https://github.com/WIZnet-ioNIC/WIZnet-ioNIC-Circuitpython