MII管理接口简介

MII管理接口（MIIM，Management Interface），MAC与PHY间的管理接口，可用来控制PHY芯片，在802.3协议中，最多可同时支持32个PHY。它由两根线组成：时钟线-MDC，双向数据线-MDIO。下面是一段从网上摘取的英文介绍：

The MDIO interface is a simple, two-wire, serial interface to connect a management entity and a managed PHY for the purposes of controlling the PHY and gathering status from the PHY.

The two lines include the MDC line [Management Data Clock], and the MDIO line [Management Data Input/Output]. The clock is point-to-point, while the data line is a bi-directional multi-drop interface.

The data line is Tri-state able and can drive 32 devices. 阅读全文 »