Q:What do emac and phy refer to?

The chip of the data link layer in the Ethernet card is called the MAC controller, and the chip of the physical layer is called the PHY. There are two common usages of emac on this platform:

  1. Emac is connected to phy through MII interface, and phy is connected to network cable through rj45

  2. Emac is connected to switch through RMII interface, switch can be divided into multiple network ports to realize multi-network port function