Hi ST Team,
First of all, I would like to thank you for your support on my previous project based on the STM32MP255D series, which has now successfully moved into production.
First of all, I would like to thank you for your support on my previous project based on the STM32MP255D series, which has now successfully moved into production.
Currently, I am working on a new project that is entirely focused on Ethernet-based communication. Below is my design requirement and a clarification request:
Project Requirement
The system requires three Ethernet interfaces in total:
Ethernet 1: Operates in standalone mode (independent network).
Ethernet 2 and Ethernet 3: Should function as switch ports, supporting STP (Spanning Tree Protocol) for loop prevention.
Network Topology and Data Flow
Ethernet 1 is used for independent communication (standalone).
Ethernet 2 connects to Device A, which is daisy-chained to Device B.
The last device (Device B) connects back to Ethernet 3, forming a potential loop in the same network domain. can i send some data from Ethernet 2/3 to devices
In this setup, I expect that when the loop is detected, STP should automatically block one of the switch ports (either Ethernet 2 or Ethernet 3) to prevent network looping.
Clarification Needed
On the STM32MP257-EV1 board, which has three Ethernet ports, can Ethernet 2 and Ethernet 3 operate simultaneously in switch configuration mode while Ethernet 1 remains standalone?
When the switch configuration is enabled, how can application-level data be transmitted through Ethernet (e.g., sending or receiving packets to/from devices connected via the switch ports)? Should the traffic be handled via the CPU Ethernet interface or directly through the switch fabric?
Your guidance on configuring and managing this Ethernet switch setup — especially with respect to STP functionality and application data routing — will be greatly appreciated.
