An example tape drive includes a magnetic tape head, an actuator, and a controller. The magnetic tape head includes a data write element to write a data track including data onto magnetic tape. The data track includes a non-trimming portion and a trimmable portion. The magnetic tape head also includes a data read element to read the data written to the non-trimming portion of the data track to verify the accuracy of the data. The controller positions the magnetic tape head via the actuator to allow (i) the data write element to write the first data track, and (ii) the data read element to read the second portion of the first data track. From the read data, a determination may be made as to whether the data was written to the non-trimming portion of the data track with a threshold level of accuracy.

A magnetic tape apparatus, in which an intensity ratio of peak intensity of diffraction peak of (110) plane with respect to peak intensity of diffraction peak of (114) plane of a hexagonal ferrite crystal structure obtained by XRD analysis of the magnetic layer by In-Plane method is 0.5 to 4.0, a vertical squareness ratio of the magnetic tape is 0.65 to 1.00, a reading element unit includes a plurality of reading elements each of which reads data by a linear scanning method from a specific track region including a reading target track in a track region included in the magnetic tape, and an extraction unit performs a waveform equalization process according to a deviation amount between positions of the magnetic tape and the reading element unit, with respect to each reading result for each reading element, to extract data derived from the reading target track from the reading result.

A magnetic tape apparatus, in which a tilt cos of the hexagonal ferrite powder with respect to a surface of the magnetic layer acquired by cross section observation by STEM is 0.85 to 1.00, a reading element unit includes a plurality of reading elements each of which reads data by a linear scanning method from a specific track region including a reading target track in a track region included in the magnetic tape, an extraction unit performs a waveform equalization process according to a deviation amount between positions of the magnetic tape and the reading element unit, with respect to each reading result for each reading element, to extract data derived from the reading target track from the reading result, and the deviation amount is determined in accordance with a result obtained by reading of the servo pattern included in the magnetic layer by a servo element.

Systems and methods are disclosed for timing servo operations within a channel based on a counter for a disc locked clock. In certain embodiments, an apparatus may comprise a servo channel configured to lock a frequency of a servo channel clock to a rotational velocity of a disc data storage medium, and maintain a counter of clock cycles for the servo channel clock. The servo channel may perform operations to read servo data from a servo sector on the disc data storage medium at a first counter value selected relative to a target counter value corresponding to an expected location of a servo timing mark (STM).

A data storage device is disclosed comprising a head actuated over a disk. A plurality of access commands are stored in a command queue, wherein the access commands are for accessing the disk using the head. A future access command is predicted, and an execution order for the access commands in the command queue is determined based on an associated execution cost of at least some of the access commands in the command queue and an associated execution cost of the future access command. At least one of the access commands in the command queue is executed based on the execution order.

A data storage device includes a first actuator and a second actuator rotatable around a common axis. The data storage device further includes a first electrical connector configured to communicate electrical signals to and from the first actuator via a first flexible circuit. The data storage device further includes a second electrical connector separate from but in a stacked arrangement with the first electrical connector. The second electrical connector is configured to communicate electrical signals to and from the second actuator via a second flexible circuit.

According to one embodiment, a disk device includes a plurality of magnetic disks, a casing, a column, a rotary component, and a screw. The casing includes a base having an inner space in which the plurality of magnetic disks is accommodated, and a first cover attached to the base to close the space. The column with a screw hole, is located in the space and is attached to the base by being fitted into a recess formed in the base. The rotary component is located in the space, surrounds the column, and is configured to rotate about the column. The screw is fitted into the screw hole through the first cover.

According to one embodiment, a magnetic disk device comprises a JIT seek control unit, which uses second time series data of a current indication value of a VCM that sets a slope having an absolute value smaller than an absolute value of a slope of a first time series data in at least one of a monotonically decreasing interval of an acceleration interval and a monotonically decreasing interval of a deceleration interval of a head or an operation acceleration of the head.

A multi-actuator hard disk drive includes a lower actuator with a corresponding voice coil motor assembly (VCMA), a coaxial upper actuator with a corresponding VCMA, and a central support plate positioned between the upper and lower VCMAs and to which the upper VCMA is fastened. Use of a central support plate enables some control over the direct and coupled plant transfer functions, while effectively providing a base support structure for the upper VCMA and enabling use of conventionally-sized fasteners.

According to one embodiment, a magnetic disk device includes a disk, a head, a command queue, a command residence time calculation unit calculating a residence time of each of commands in the command queue, a command information calculation unit calculating the number of the commands and a ratio, a limit time determination unit obtaining a latency limit time corresponding to the number of commands and the ratio, from a latency limit time determination table, and a command selection processing unit selecting a command to be executed, by considering the latency limit time.