Abstract: In a magnetic recording drive that includes a shingled magnetic recording (SMR) region and a conventional magnetic recording (CMR) region, the quantity of validation data that is stored by the CMR region is reduced. In the magnetic recording drive, verification data stored in the CMR region is invalidated under certain circumstances, including when an SMR band is closed, when an SMR band is indicated by a host to be reused, when an SMR band is indicated to be finished, and when a last data track of an SMR has data stored therein.

Abstract: In a disk drive, when an off-track error occurs during a sequential disk access operation that spans multiple contiguous data tracks, efficient recovery is performed. In an embodiment, the disk access operation (e.g., reading from or writing to a disk) is attempted for all sectors of the sequential disk access operation. The disk access operation is then attempted again for sectors associated with any off-track errors that occurred during the disk access operation. In another embodiment, when an off-track error occurs during a sequential write operation in a shingled magnetic recording drive, the data originally targeted to be written to a first portion is written to a second portion of the data track that follows the first portion. Since no additional revolutions of the disk are needed for data associated with the sequential write operation to be written to the disk.

Abstract: A hybrid drive and associated methods provide low-overhead storage of a hibernation file in the hybrid hard disk drive. During operation, the hybrid drive allocates a portion of solid-state memory in the drive that is large enough to accommodate a hibernation file associated with a host device of the hybrid drive. In addition to the erased memory blocks that are normally present during operation of the hybrid drive, the portion of solid-state memory allocated for accommodating the hibernation file may include over-provisioned memory blocks, blocks used to store a previous hibernation file that has been trimmed, and/or non-dirty blocks.

Abstract: In various embodiments, an apparatus includes a processor, a read only memory communicatively coupled to the processor, and a visibility port associated with the apparatus. The visibility port provides information about the processor and the read only memory to the port, with the read only memory including at least a portion of cryptographic information. A visibility port disabler masks the visibility port during cryptographic operations of the processor.

Abstract: Random numbers are generated in a storage device based on the parity bits of successive position error signal (PES) samples. The parity bits of multiple PES samples are concatenated to form a random number having a desired number of bits. The random number may be further randomized by being processed with a deterministic random bit generator (DRBG) included in the firmware of the storage device.

Abstract: A disk drive includes a first flush cache memory location, a second flush cache memory location, and a controller for writing information associated with a flush cache write command alternatively between the first flush cache memory location and the second flush cache memory location.

Abstract: An information storage device is protected from unauthorized access by requiring periodic re-authentication of user credentials. Failure to correctly re-authenticate within a time window results in the automatic locking of the portions of the storage device that have been previously enabled for the user so that they are no longer accessible.

Abstract: A storage device configured with a user-addressable LBA space stores an initial boot image in a region of the LBA space that is outside the user-addressable LBA space. Updates to the initial image are carried out as an unencrypted process when speed is desired. A second copy of the initial boot image may be maintained by the storage device to provide for update flexibility. When two copies of the initial boot image are maintained, one is designated as active and the other is used for updates. When an update to a copy is completed, that copy is designated as being active.

Abstract: Firmware is securely downloaded from a host to an information storage device using an encryption key generated by the information storage device. The encryption key is generated in response to a firmware download request by the host. The host encrypts the firmware image with the encryption key and downloads the encrypted firmware image to the information storage device. The information storage device receives the encrypted firmware image, decrypts the firmware image, and updates its firmware with this firmware image.

Abstract: A hard disk drive, and methods of providing secure access to data on a hard disk drive, are shown. In one example, an access code is sent to a hard disk drive to decipher an encrypted user key stored on the hard disk drive. In one example, at least a portion of the access code is not stored anywhere within the hard disk drive, and is provided from a host.

Abstract: A method for authenticating software for use in a device includes encrypting software to be input to a device with a private key, and decrypting the software presented to the device with a public key retrieved from a memory accessible by the device.

Abstract: A disk drive includes a first flush cache memory location, a second flush cache memory location, and a controller for writing information associated with a flush cache write command alternatively between the first flush cache memory location and the second flush cache memory location.

Abstract: Systems and methods in accordance with embodiments of the present invention can be applied to determine the position of a ramp relative to an actuator. In one embodiment, a system in accordance with the present invention includes a rotatable medium having a first track assigned to a track located a distance from the ramp, rather than a distance from an average acquire track, thereby maximizing the size of a data region. A track density can be reduced for a given hard disk drive capacity, or alternatively the hard disk drive capacity can be maximized for a given track density.

Abstract: The present invention comprises an implementation of a variable data TPI hard drive system. In one embodiment, the system is implemented by configuring a group of servo tracks in a radial direction for a hard drive media. The group is comprised of an integral number of servo tracks that is constant throughout the drive device. The number of data tracks in a group is also an integer but will vary for each surface according to the head used for R/W operations for each media surface. Group boundaries coincide with media surface R/W zone boundaries. The groups are accessed in hard drives having multiple surfaces in a serpentine manner. Data tracks per group are reduced from what is achievable to produce desired target capacities.

Abstract: The present invention comprises an implementation of a variable data TPI hard drive system. In one embodiment, the system is implemented by configuring a group of servo tracks in a radial direction for a hard drive media. The group is comprised of an integral number of servo tracks that is constant throughout the drive device. The number of data tracks in a group is also an integer but will vary for each surface according to the head used for R/W operations for each media surface. Group boundaries coincide with media surface R/W zone boundaries. The groups are accessed in hard drives having multiple surfaces in a serpentine manner. Data tracks per group are reduced from what is achievable to produce desired target capacities.

Abstract: The initial attempt to servowrite a wedge in the final pattern may fail due to disk defects and a retry of servowriting the failed wedge is usually attempted. The current invention shifts the position of the final wedge during at least one such servowriting retry attempt. Since a final wedge position different from a previous self servowriting attempt is adopted, potential defects on the surface of the media can possibly be avoided and the success rate of the servowriting retry attempt can be improved. In practice, this involves carrying a count of failed wedges during the servowrite process and if it exceeds a threshold level, then the wedge pattern is shifted in position and the servowrite process starts again. This can be repeated for many shift positions. This description is not intended to be a complete description of, or limit the scope of, the invention. Other features, aspects, and objects of the invention can be obtained from a review of the specification, the figures, and the claims.

Abstract: Methods and computer program products for determining accurate estimates of coil resistance are provided. Current differences between pairs of current values are determined. Additionally, voltage differences between pairs of actuator coil voltages (corresponding to the current values) and angular velocity differences between pairs of angular velocities are determined. Coil resistance is estimated based on the current differences, the voltage differences and the angular velocity differences. These coil resistance estimates can be useful for accurately estimating actuator coil, actuator arm and/or head velocity.

Abstract: Methods and computer program products for determining accurate estimates of coil resistance are provided. Current differences between pairs of current values are determined. Additionally, voltage differences between pairs of actuator coil voltages (corresponding to the current values) are determined. Coil resistance is estimated based on the current differences and the voltage differences. These coil resistance estimates can be useful for accurately estimating actuator coil, actuator arm and/or head velocity.

Abstract: Methods in accordance with the present invention can be applied to reduce frictional effects in a bearing of a rotary actuator on the motion dynamics of the rotary actuator. In one such method a disk having a first magnetic servo pattern on a surface written, for example, by a media writer, is rotated at a first frequency. The first magnetic servo pattern is read using a head. A second magnetic servo pattern based on the first magnetic servo pattern can be written to the surface by the head such that the second magnetic servo pattern is defined by the oscillation of the head at a second frequency. This description is not intended to be a complete description of, or limit the scope of, the invention. Other features, aspects, and objects of the invention can be obtained from a review of the specification, the figures, and the claims.

Abstract: Ramp arrangements and methods in accordance with the present invention can provide the position or velocity of an actuator assembly in a rotating media data storage device while loading or unloading a head connected with the actuator assembly from a disk. One such arrangement comprises a conductive ramp electrically coupled to a conductive suspension lift tab such that a closed circuit is formed when the head is unloaded from the disk. As the suspension lift tab slides along the ramp, the resistance of the circuit changes. By measuring multiple positions at multiple times, a head velocity can be determined. This description is not intended to be a complete description of, or limit the scope of, the invention. Other features, aspects, and objects of the invention can be obtained from a review of the specification, the figures, and the claims.