Patent ID: 7194502

Claim:
An apparatus for controlling a physical layer interface of a network interface card, said apparatus comprising: a read only memory (ROM) capable of storing an embedded control program; a random access memory capable of storing a downloadable software control program downloaded from an external processing system; and a microcontroller capable of controlling said physical layer interface, wherein said microcontroller in a first operating mode is capable of executing said embedded control program to thereby control said physical layer interface, and wherein said microcontroller in a second operating mode is capable of executing said downloadable software control program in place of said embedded control program to thereby control said physical layer interface; wherein said microcontroller comprises a plurality of control registers capable of controlling said first and second operating modes, wherein said microcontroller switches from said first operating mode to said second operating mode when said external processing system stores a jump address to said RAM in a first one of said plurality of control registers.