RAK3172 + RUI3: driving a W5500 (or W5100S) Ethernet controller over SPI - any working path?

LPWAN Modules / EVBs
1

Hi,

I’m building a LoRa P2P gateway based on RAK3172 (RAK3272S breakout for prototyping, custom PCB later). It receives packets from battery-powered RAK3172 nodes and forwards them to a server over Ethernet.

I’d like to avoid adding a second MCU, so I want to drive a WIZnet Ethernet controller directly from the RAK3172 over SPI.

W5500 is the deciding factor for us. W5500 modules are roughly 3x cheaper than W5100S ones (about $4 vs $12) and have better specs. If only W5100S turns out to be viable, the saving over simply using a separate ESP32 + Ethernet board is too small to justify the extra work - so we would just use the ESP32 board instead.

Questions:

  1. Is there a working path to driving a W5500 from RAK3172 under RUI3? Has anyone ported a standard Arduino Ethernet library (the W5500-based Ethernet / Ethernet2 library) to RUI3?

  2. In this thread a W5500 attempt using the RAK13800_W5100S library hung at writeMR(0x80) during the Wiznet soft reset: RAK3272-SiP and W5500 Ethernet controller - Since the SPI frame format differs between W5100/W5100S and W5500, my guess is that the library simply does not speak W5500. Is that the right diagnosis, or is something else involved (SPI mode, timing, CS handling in RUI3)?

  3. As a fallback: is the RAK13800 (W5100S) library usable under RUI3 on RAK3172? The WisBlock examples appear to target nRF52 / ESP32 cores.

Setup: RAK3172, RUI3, SPI on PA4-PA7. The gateway is mains-powered, so there is no low-power constraint. Traffic is tiny - a few dozen bytes every 10 minutes from about 6 nodes.

Thanks!

2

I can’t help with W5500 Ethernet controller, but our Ethernet module with the W5100 works fine in RUI3 and RAK3372 (WisBlock version of RAK3172).

Log:

RAK13800 Ethernet HTTP Client example.
------------------------------------------------------
Setup the device with WisToolBox or AT commands before using it
Version RUI3-Ethernet-V1.0.0
------------------------------------------------------
[UPLINK] Start
[UPLINK] Send packet with size 4 over P2P
[UPLINK] Packet enqueued
Initialize Ethernet with DHCP:
DHCP assigned IP 192.168.0.46
connecting to www.google.com...
connected to 142.251.154.119
Current Work Mode: LoRa P2P.
[UPLINK] Start
[UPLINK] Send packet with size 4 over P2P
[UPLINK] Packet enqueued
HTTP/1.1 200 OK
Content-Type: text/html; charset=ISO-8859-1
Content-Security-Policy: object-src 'none';base-uri 'self';script-src 'nonce-7uUey8wX7kMd2Yaqow3Cqw' 'strict-dynamic' 'report-sample' 'unsafe-eval' 'unsafe-inline' https: http:;r
[TX-P2P-CB] P2P TX finished
+EVT:TXP2P DONE

test code:
RAK3372-P2P-Ethernet.ino (8.2 KB)