Four physical interface types are available for the core:
- GMII
- The GMII is defined by the IEEE802.3 specification. It can provide support for Ethernet operation at 10 Mbps, 100 Mbps, and 1 Gbps speeds.
- MII
- The MII is defined by the IEEE802.3 specification. It can provide support for Ethernet operation at 10 Mbps and 100 Mbps speeds.
- RGMII
- The RGMII is, effectively, a Double Data Rate version of GMII. It can provide support for Ethernet operation at 10 Mbps, 100 Mbps, and 1 Gbps speeds.
- Internal
- The core is generated with no physical interface and is ready for connection to an internal PHY such as the Ethernet 1G/2.5G PCS/PMA or SGMII LogiCORE.
The choice of physical interface determines the content of the example design delivered with the core where the external GMII, MII or RGMII is described in HDL. There is no change in the core HDL between RGMII, GMII, or Internal. If MII is selected, the physical interface datapath is reduced to four bits. The default is to use GMII.