Ethernet link status for the K64F

Dependents:   JRO_CR2 K64F_EthLink_HelloWorld frdm_test JRO_DDSv2

Simple K64F technique to determine if the Ethernet PHY link is up or down. The routine utilizes the Ethernet MII interface to gain access to the Ethernet PHY which contains the actual link status.

I wrote this because the mbed Ethernet function does not recognize its own "int link();" function with the K64F.