Patent ID: 8918663

Claim:
A method for active power management in a Serial ATA (SATA) interface for data transfer between a host and a device, comprising: receiving, by the host, an instruction to enter a power saving mode, the power saving mode having a predetermined data transfer rate at which the host is not to exceed when transferring data to lower power consumption during data transfer; after receiving the instruction to enter the power saving mode, during a SATA stage in which a maximum data transfer rate is established: communicating by the host with the device to determine a highest data transfer rate at which the host can communicate with the device such that the device learns the highest data transfer rate; after communicating with the device to determine the highest data transfer rate, receiving, by the host from the device, a first SATA request to conduct data transfer at a first data transfer rate greater than the predetermined data transfer rate that is less than the highest data transfer rate at which the host is able in actuality to conduct data transfer; in response to receiving the first SATA request, refusing the first SATA request from the device by the host; after refusing the first SATA request, receiving, by the host from the device, a second SATA request to conduct data transfer at a second data transfer rate less than the first data transfer rate and no greater than the predetermined data transfer rate; and in response to receiving the second SATA request, accepting the second SATA request from the device by the host, such that data transfer is conducted at the second data transfer rate without data transfer having been conducted at the first data transfer rate.