One or more magnetic recording disks are coupled to a spindle motor, each of the disks having opposing recording surfaces. Two or more actuators are moveable independently over at least a first recording surface of the one or more disks. A first actuator of the two or more actuators comprises a first write head and a first read head. A second actuator of the two or more actuators comprises at least a second read head and may include a second write head. A controller is coupled to the two or more actuators and configured to write data to a track on the first recording surface using the first write head, and perform a read operation on the data written to the track using the second read head. The controller is also configured to verify that the data was successfully written to the track in response to the read operation. The read operation can be performed within less than one revolution of the first recording surface after the write operation.

A multimedia visual progress indication system that provides a cache bar that is overlaid onto the program material or displayed on a dedicated display. A cache bar indicates the length of a recording session or the length of stored program material and expands to the right when material is being recorded. Index and/or bookmark indicators are displayed next to the cache bar. A position indicator moves within the cache bar and tells the user visually where his current position is within the program material. Numeric time or counter mark of the current position is displayed in the vicinity of the cache bar. The trick play bar and its associated components are displayed for a predetermined time period.

Disclosed is an optical disk drive for wireless power transmission. The optical disk drive in an embodiment of the present invention comprises a tray on which a optical disk is to be seated; a driving unit for rotating the optical disk to be seated on the tray and reading or writing the optical disk; a wireless power transmitting module to be seated on the tray and comprising a primary coil and a transmitting circuit unit; a power supply unit for supplying power; and a controller for controlling the power supply unit to supply power to the wireless power transmitting module when determining that the wireless power transmitting module is seated on the tray

A method is provided for judging whether a double-sided optical disc is placed reversely. Firstly, the disc is loaded. Then, a first optical pickup head emits a first laser beam to a first specified area of the disc and receives a first reflected laser beam. A second optical pickup head emits a second laser beam to a second specified area of the disc and receives a second reflected laser beam. If the first reflected laser beam generates an alternate brightness and darkness change and the second reflected laser beam does not generate the alternate brightness and darkness change, the disc is not placed reversely. If the first reflected laser beam does not generate the alternate brightness and darkness change and the second reflected laser beam generates the alternate brightness and darkness change, the disc is placed reversely.

A method comprises creating calibration data using a first control circuitry of an apparatus, replacing the first control circuitry with a second control circuitry in the apparatus, and operating the apparatus with the second control circuitry using the calibration data. As an example, the apparatus may be a disc drive. The second control circuitry may be substantially similar to the first control circuitry such that calibration measurements using the first control circuitry are applicable to the second control circuitry. The first control circuitry may be included in a circuit board that is replaced with a second circuit board including the second control circuitry. In an exemplary embodiment, the second circuit board may include different and/or additional components relative to the first circuit board, such as integrated video inputs and/or video control circuitry.

An optical disc apparatus includes: a controller configured to acquire information of an access result and access positions on an optical disc when an optical disc drive unit configured to optically access an optical disc optically accesses the optical disc; and a storage configured to store the information acquired by the controller.

An embodiment of the invention provides a phonorecord for embodying an audio recording. The phonorecord can comprise a substrate and a conformal coating disposed on at least a portion of the substrate. The substrate can comprise one or more grooves embodying the audio recording.

A method is provided for judging whether a double-sided optical disc is placed reversely into an optical disc drive. The optical disc drive includes a first control module and a second control module. The first control module includes a first optical pickup head. The second control module includes a second optical pickup head. Firstly, the double-sided optical disc is loaded. Then, the first optical pickup head of the first control module emits a laser beam to a specified area of the double-sided optical disc and receives a reflected laser beam from the specified area. If the reflected laser beam generates an alternate brightness and darkness change, the double-sided optical disc is not placed reversely. If the reflected laser beam does not generate the alternate brightness and darkness change, the double-sided optical disc is placed reversely.

One or more magnetic recording disks are coupled to a spindle motor, each of the disks having opposing recording surfaces. Two or more actuators are moveable independently over at least a first recording surface of the one or more disks. A first actuator of the two or more actuators comprises a first write head and a first read head. A second actuator of the two or more actuators comprises at least a second read head and may include a second write head. A controller is coupled to the two or more actuators and configured to write data to a track on the first recording surface using the first write head, and perform a read operation on the data written to the track using the second read head. The controller is also configured to verify that the data was successfully written to the track in response to the read operation. The read operation can be performed within less than one revolution of the first recording surface after the write operation.

In a data storage device where a data writer is predicted to fail, cold data can be identified and subsequently moved to a data storage medium corresponding to the failing data writer. The data writer may be positioned proximal the data storage medium where data is stored. A controller can predict the failure in the data writer and transition all the data in the data storage medium to a read only status.