A data recording apparatus including: a data reading device configured to read data from a first recording medium and configured to store data and first management data for managing the data by file; a data recording device configured to record data on a second recording medium; a management data producing device configured to produce second management data for managing data recorded on the second recording medium based on the first management data of the first recording medium on which the data recorded on the second recording medium has been recorded; a data determining device configured to determine data unrecorded on the second recording medium by comparing the first management data read by the data reading device from the first recording medium with the second management data recorded on the second recording medium; a control device configured to read the data determined by the data determining device from the first recording medium and cause the recording device to record the read data onto the second recording medium; and a display device configured to display the recording status of data, managed by the first management data read by the reading device from the first recording medium, on the second recording medium, wherein the recording status includes one of recording of data complete, recording of data in progress, and recording of data yet to begin.

According to one embodiment, an electronic apparatus includes, for example, a casing having an opening with a perimeter, and a circuit board including a first surface facing away from the casing and a second surface facing the casing, a first conductor which extends over the opening in the casing and at least a portion of which is located over the first surface, a second conductor at least portion of which extends over the second surface and is exposed to the interior of the casing at the opening in the casing, and a third conductor extending through the first surface and the second surface and electrically connected to the first conductor and the second conductor at a location outward of the perimeter of the opening.

A magnetic disk device includes a magnetic disk that includes a plurality of zones divided in a radial direction, a plurality of tracks in each of the zones, and a plurality of sectors in each of the tracks divided in a circumferential direction, a magnetic head configured to read and write data to and from the magnetic disk, and a control unit configured to determine a setting value of a recording current to be applied to the magnetic head when writing to each of a plurality of sections of a first sector, based on error rates in data read from a second sector that is in the same zone as the first sector and to which a write was performed while changing setting values of recording currents applied to the magnetic head while writing to each of a plurality of sections of the second sector.

According to one embodiment, a magnetic disk device includes a first magnetic disk, a second magnetic disk, a first actuator with a first head which reads/writes data from/to the first magnetic disk, a second actuator with a second head which reads/writes data from/to the second magnetic disk, the second actuator operated independently from the first actuator, a first controller configured to retracts the first actuator at a first time, and a second controller configured to retract the second actuator at a second time which is shifted from the first time by a certain period of time.

When a shingled magnetic recording (SMR) hard disk drive (HDD) performs additional SMR band copy and/or flush operations to ensure that data associated with logical bands that are adjacent or proximate in logical space are stored in physical locations in the SMR HDD that are proximate in physical space. As a result, efficient execution is ensured of read commands that span multiple logical bands of the SMR HDD.

A method of setting an upper limit value of the number of write times, which is applied to a magnetic disk device including a disk and a head configured to write data to the disk and read the data from the disk, includes measuring a plurality of bit error rates in a recording area of the disk upon repeatedly writing to an area of the disk adjacent to the recording area a number of write times, deriving a function that approximates a bit error rate in relation to a number of write times, using the measured bit rates corresponding to at least a first number of write times, a second number of write times, and a third number of write times, and applying the function to determine a number of write times that correspond to a first threshold bit error rate that makes the data on the disk unreadable, and setting the determined number of write times as the upper limit value of the number of write times.

A circuit includes a set of input nodes configured to be coupled to respective ones of the windings of a spindle motor in a hard disk drive to sense the voltages applied to the windings. A set of output nodes is configured to provide output signals indicative of direction of flow of the currents through the windings. Level shifters are coupled to respective input nodes in the set of input nodes and have level-shifted output nodes configured to provide down-shifted replicas of the voltages at the respective input nodes in the set of input nodes. Flip-flops have inputs coupled to respective ones of the level-shifted output nodes of the level shifters and outputs configured to provide the output signals coupled to respective output nodes.

A data recording apparatus including: a data reading device configured to read data from a first recording medium and configured to store data and first management data for managing the data by file; a data recording device configured to record data on a second recording medium; a management data producing device configured to produce second management data for managing data recorded on the second recording medium based on the first management data of the first recording medium on which the data recorded on the second recording medium has been recorded; a data determining device configured to determine data unrecorded on the second recording medium by comparing the first management data read by the data reading device from the first recording medium with the second management data recorded on the second recording medium; a control device configured to read the data determined by the data determining device from the first recording medium and cause the recording device to record the read data onto the second recording medium; and a display device configured to display the recording status of data, managed by the first management data read by the reading device from the first recording medium, on the second recording medium, wherein the recording status includes one of recording of data complete, recording of data in progress, and recording of data yet to begin.

According to one embodiment, a magnetic disk device includes a disk that includes a plurality of tracks, each track including a plurality of sectors for storing data, a head that is for writing data to the plurality of sectors and reading data from the plurality of sectors, and a controller. The controller is configured to determine that a first sector of the plurality of sectors is not able to be read and is a defective sector, determine that a second sector of the plurality of sectors is disposed along a line that extends through the first sector and a defective sector included in a first list of defective sectors, register the second sector in the first list of defective sectors, and reallocate an address corresponding to the second sector to a first alternative sector included on the disk.

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.