Overview

Secure Pi SP2302 single-board computer now supports dual Ethernet functionality using the WIZ850io module, which is based on the W5500 chip from WIZnet. This enables robust SPI-based Ethernet communication — ideal for industrial IoT, secure networking, and embedded applications.

SPI interface and provides a second Ethernet port, allowing the system to handle dual-network environments. The primary Ethernet interface (eth0) remains native, while the secondary (eth1) is handled by the W5500.

Hardware Connection & Pin Assignment

To connect the WIZ850io module to the SP2302 via SPI, please wire the following pins:

Function	SP2302 Extended 40 Pins	WIZ850io Pin
MISO	SPI2_MISO	MISO
MOSI	SPI2_MOSI	MOSI
SCLK	SPI_CLK	SCLK
CS (Chip Select)	SPI_CS0	SCNn
RESET	GPIO35	RSTn
Interrupt	GPIO34	INTn
GND	GND	GND
VCC (3.3V)	3V3	3.3V

Note: Please fill in the actual SP2302 pin assignments in the table above based on your board’s layout or pinout documentation.

 Firmware Installation for Dual Ethernet

To enable the W5500, you must use the dual-port firmware designed for the SP2302 platform. This firmware includes:

• SPI driver support for W5500
• netplan compatibility
• Udev rules for automatic recognition of W5500 as eth1

Steps:

1. Flash the dual Ethernet firmware to the SP2302 using standard flashing tools (e.g., dd or etcher)
2. Reboot the device after flashing

Post-Installation Testing & Setup

Once the firmware is flashed, follow these steps to verify and activate the second Ethernet port:

1 Check W5500 Device Status Using dmesg

Run the following command to check if the W5500 is detected:

bash

dmesg | grep -e 5500 -e 5100

You should see log entries indicating the SPI initialization and W5500 network driver being loaded.

2 Verify Second Ethernet Interface (eth1)

Check for the presence of eth1:

bash

ifconfig -a

You should see both eth0 (native) and eth1 (W5500 via SPI).

If eth1 is not listed, ensure SPI is enabled, the wiring is correct, and the chip is receiving power.

3 Configure netplan to Use DHCP on W5500 (eth1)

Edit or create a netplan configuration:

bash

vi 01-network-manager-all.yaml

Paste the following:

network:  
    version: 2  
    renderer: NetworkManager
    ethernets:    
        eth1:      
            dhcp4: true

Apply the configuration:

bash

sudo netplan apply

Wait a few seconds, then check for an IP address:

bash

ip addr show eth1

4 Test Internet Connectivity Over W5500

Try pinging Google using eth1:

bash

ping -I eth1 google.com

You should receive replies indicating successful communication through the W5500 Ethernet interface.

 Summary

Step	Task	Status Indicator
1	W5500 detected via SPI (dmesg)	W5500 logs appear
2	Second interface created	eth1 appears in ip link show
3	Netplan configured	eth1 gets IP from DHCP
4	Internet connectivity	Successful pings through eth1

📎 Notes

• Ensure SPI is enabled in the device tree or bootloader settings if needed.
• Use a stable 3.3V power source for the WIZ850io to avoid instability.
• Static IP configuration can also be set via netplan if required.