Patent ID: 8565269

Claim:
A method, comprising: transitioning a bus between a media access control device and a physical layer device from an active mode to an energy saving mode, wherein during said energy saving mode, a first part of a media access control device interface that is coupled to said bus and a first part of a physical layer device interface that is coupled to said bus are powered down; and while in said energy saving mode, operating a second part of said media access control device interface and/or a second part of said physical layer device interface in a powered mode that enables generation of an adjusted clock signal that is transmitted across said bus, said adjusted clock signal being used to maintain synchronization between said media access control device and said physical layer device, wherein said adjusted clock signal is generated by reducing a duty cycle of a clock to a non-zero duty cycle that is lower than a duty-cycle of said clock when said bus is in said active mode, wherein said adjusted clock signal has multiple periodic cycles in a first time period having a reduced frequency and/or amplitude, and a second time period where no clock signal is generated.