I'm currently working on a project involving the STM32H573 microcontroller and the LAN8742A Ethernet PHY. My goal is to implement a simple Ethernet loopback test to verify the basic functionality of the Ethernet interface. Could you please provide if you have anything?
My understanding is that you want to implement an example without any middleware to test Ethernet controller functionality my recommendation is to have a look at the following article:
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The LAN8742A can do internal loopback (without any external connection or cable). See the data sheet, 3.8.10 Loopback operation. This section also explains how to make a connector for external loopback.
