Microcomputer system having upper bus and lower bus and controlling data access in network

摘要

An MDIO interface transmits and receives data to and from a host device through an upper serial bus. An MDIO interface transmits and receives data to and from a client device through a lower serial bus. A CPU controls the MDIO interface and the MDIO interface, and controls data transfer between the host device and the client device. It is, therefore, possible that the CPU controls the client device connected to the lower serial bus.