Patent ID: 8681448

Claim:
A data storage system, comprising: a magnetic head; a drive mechanism for passing a magnetic tape over the magnetic head; and a controller electrically coupled to the drive mechanism, the controller being configured to: determine a reference velocity at various intervals; receive or determine a secondary velocity based at least in part on a parameter associated with a motor of the drive mechanism; determine a value representative of a difference between the reference velocity and the secondary velocity; adjust a speed of the motor of the drive mechanism for minimizing the difference between the reference velocity and the secondary velocity; receive or determine a primary velocity based on reading information encoded on a magnetic tape; at a switching point, make the reference velocity about equal to the primary velocity; after the switching point, determine the reference velocity at various intervals; after the switching point, determine a value representative of a difference between the reference velocity and the primary velocity; and adjust the speed of the motor of the drive mechanism for minimizing the difference between the reference velocity and the primary velocity.