STM32连接Marvell交换芯片88E6176的PHY

​​​http://xinzero.com/explain-phy-configuration-in-lwip.html​​​
​​​https://www.amobbs.com/thread-5521899-2-1.html​​​
​​​http://bbs.21ic.com/icview-158331-1-1.html​​