RAK3272-SiP and W5500 Ethernet controller
Discussion about using RAK13800_W5100S Arduino library while building RAK3272-SiP-based module with W5500 to handle dual communication channels using SPI.
RAK - RAK3272-SiP Breakout Board
x 1
WIZnet - W5500
x 1
🔎 Context
The original poster wanted to build a custom RAK3272-SiP-based module with a W5500 Ethernet controller to handle dual communication channels using SPI. They tried using the RAK13800_W5100S Arduino library (designed for the W5100/W5100S) but ran into problems: detection works, but the system hangs after Ethernet.begin(), both in DHCP and static IP modes.
🧪 What Happened
1. Initial Setup & Symptoms
The setup includes the RAK3272-SiP connected to a W5500 module over SPI.
The Arduino sketch detects the module (via SPI); if it’s not present it reports “no module”.
However, once Ethernet.begin(mac) is called, the code stalls during Ethernet initialization — seemingly hanging during the Wiznet reset/init sequence.
🔧 Wiring & Pins Discussion
The OP wired only the 4 core SPI lines (MOSI, MISO, SCLK, CS).
They asked whether other pins (like reset or interrupt) need to be connected for the library to work properly instead of just the 4 SPI pins.
🗣️ Community Guidance & Insights
Another contributor warned that pin conflicts on the RAK3272-SiP can occur if multiple peripherals share the same pins — especially when adding custom hardware. Confirming correct SPI and CS wiring is essential.
It was noted that in WisBlock modules (e.g., RAK13800 Ethernet modules using W5100) additional signals like Reset (RSTn) and Interrupt (INTn) play a role, and the equivalent pins should be mapped appropriately when using W5500.
One responder posted the RAK3272-SiP pin definitions from the Arduino core (mapping SPI and general I/O), helping clarify which SiP pins correspond to the SPI signals used.
🧠 Troubleshooting & Outcome
After incorporating advice, the OP attempted further hardware tests using a breadboard to verify wiring.
They modified the Wiznet driver code with additional debug prints and found that the initialization appeared to hang inside the Wiznet soft-reset routine.
At the time of the last update in the thread, the OP mentions no working solution yet and plans to try a W5100S-based board next, suspecting the library might not fully support the W5500 in this context.
