Patent ID: 9019651
Filing Date: 2015-04-28
Classification: G11B

Abstract:
1. A computer program product for controlling first head and a second head in a drive to access data on a recordable storage media, the computer program product comprising a computer readable storage medium having computer readable program code embodied therein that executes to perform operations, the operations comprising: reading, with the first head, first and second position information from a servo pattern on the recordable storage media; determining a first difference with respect to a direction of movement of the recordable storage media based on the read first and second position information; reading, with the second head, third and fourth position information from the servo pattern; determining a second difference with respect to the direction of movement of the recordable storage media based on the read third and fourth position information; calculating an offset based on the determined first and second differences; and using the calculated offset to generate an error signal to adjust the first and second heads during read and write operations with respect to the recordable storage media.