The Ethernet function transmits and receives signals on the Control bus. The function implements the media access control (MAC) and complies with the IEEE standard 802.3. The Ethernet function selected for this example is from CoreEl Microsystems. This function supports both reduced media independent interface (RMII) and media independent interface (MII) to the physical Ethernet layer, which is implemented off-chip. The instantiation in this example uses the MII interface and supports a 16-bit host interface.