Patent ID: 8004988

Claim:
A stand alone Ethernet controller comprising: an interface for coupling the stand alone Ethernet controller with an external processor; a system control unit coupled with said interface, wherein the system control unit receives and decodes commands received from the external processor through said interface; an Ethernet input and output port; a buffer memory for storing data packets received by the Ethernet input port from an external device, wherein the system control unit performs read and write accesses to the buffer memory; a data flow control unit coupled with the Ethernet output port for controlling the data flow to the Ethernet controller; a packet counter; packet counter control logic for incrementing and decrementing the packet counter, wherein said packet counter is incremented when a data packet has been written into the buffer memory and decremented when said system control unit processed a packet read command received through said interface from the external processor; a first register for storing a first watermark; a comparator logic coupled to the packet counter and the first register for sending control signals to the data flow control unit, wherein when a packet counter value is greater or equal to said first watermark, an Ethernet transmission signal is sent to the external device which prevents the external device from further transmissions to the stand-alone Ethernet controller.