说明：  网络芯片smc91c1113的datasheet. 详细的介绍了网络的mac和phy，如何实现的。同时里面也有驱动编写的demo
(Network chip smc91c1113 the datasheet. A detailed introduction of a network of mac and phy, how to achieve. At the same time, there is also driving the preparation of the demo)