摘要:
A method for registering a defect map within a hard disk drive is disclosed. A hard disk drive includes a recording disk, a head assembly, and a controller. Multiple sectors are formed on the recording disk, and the head assembly includes a head for reading/writing data from/to the recording disk. The controller, which controls the head assembly to read/write data from/to the recording disk, includes a defect sector positional information holding device and a sector identification device. The defect sector positional information holding device holds positional information of a defect sector disabled to read/write data therefrom/thereto the recording disk. The positional information includes the number of the defect sectors continued in a circumferential direction and in a radial direction of the recording disk. The sector identification device refers to the positional information of the defect sector so as to identify a target sector from/in which data is to be read/written when a read/write command is received from a host computer.
摘要:
An error recovery procedure (ERP) in a storage device such as a rotating magnetic hard disk drive is executed to the last step regardless of the established time-out period for an instruction, thereby more reliably recovering from errors. In accordance with one embodiment of the invention, when a disk drive receives a reset instruction from a host during the execution of an ERP, it executes the ERP until the error is recovered, or to the last step without interrupting the ERP. Further, in accordance with another embodiment of the invention, when a disk drive receives a reset instruction during the execution of an ERP, it stops execution of the ERP and holds the number K of the step which was completed immediately before stopping, and when receiving a retry instruction after that, sequentially executes the ERP from the K+1-th error recovery step.
摘要:
An improved magnetic recording medium is disclosed, particularly a magnetic tape suitable for sound recording and video recording, which comprises as a recording element a mixture of cobalt-containing iron oxide magnetic particles consisting essentially of ferromagnetic iron oxide particles containing cobalt and optionally a divalent iron in the most outer layer thereof, and .gamma.-ferric oxide particles in the ratio of 10:90 to 50:50 by weight, said mixture of cobalt-containing iron oxide magnetic particles and .gamma.-ferric oxide particles being applied to a substrate (e.g. a polyester film) with a binding agent. The magnetic recording medium has excellent electromagnetic transducing properties and improved charging properties and is useful for conventional magnetic recording apparatus used at normal position with high sensitivity in wide range of frequency.
摘要:
To decrease the number of read errors of a storage device due to bus noise when data is transferred between a host apparatus and the storage device. When a read error due to bus noise is detected, transfer of data to a host apparatus is temporarily stopped when executing rereading to eliminate bus noise which is a cause of the read error. In a preferred embodiment bus noise errors are distinguished by looking at the frequency of errors and the retry count for the previous error. The error is detected as a bus noise error if the frequency is above a threshold and the retry count is below a threshold. Data transfer can be restarted when a buffer becomes full or when the reading of the data is successfully completed.
摘要:
Cobalt-containing iron oxide magnetic particles having a high coercive force and a small surface electrical resistance which are useful as a recording element for a magnetic recording medium, and a method for the preparation of the same comprising reducing acicular .gamma.-Fe.sub.2 O.sub.3 particles in a reducing gas or liquid until the iron oxide reaches an intermediate oxidation state between .gamma.-Fe.sub.2 O.sub.3 and Fe.sub.3 O.sub.4, dispersing the resulting iron oxide particles into an aqueous solution containing a cobalt salt and optionally a ferrous salt and an alkali of one equivalent or more to the metal salt(s), and heating the mixture at a temperature of higher than room temperature up to a boiling point of the mixture under an atmospheric condition such that the divalent iron is substantially not oxidized. The cobalt is thereby predominantly incorporated into the most outer layer of the acicular iron oxide particles.
摘要翻译:可用作磁记录介质的记录元件的具有高矫顽力和小表面电阻的含钴氧化铁磁性颗粒及其制备方法包括还原针状γ-Fe2O3颗粒的还原性 气体或液体,直到氧化铁在γ-Fe 2 O 3与Fe 3 O 4之间达到中间氧化态,将得到的氧化铁颗粒分散到含有钴盐和任选的亚铁盐和一当量或更多的碱金属盐的水溶液中 并在大气条件下在高于室温的温度下将该混合物加热到混合物的沸点,使得二价铁基本上不被氧化。 因此,钴主要并入针状氧化铁颗粒的最外层。
摘要:
A magnetic recording medium which comprises a first magnetic layer on a base and a second magnetic layer over the first magnetic layer, the second magnetic layer containing magnetic particles having an average particle length (long axis diameter) of not more than 0.35.mu. , with a coercive force of from 660 to 760 oersteds, and the ratio of the coercive force of the upper or second magnetic layer to that of the lower or first magnetic layer being 1.1/1 to 1.6/1. The resulting magnetic recording medium has excellent sensitivity and frequency characteristics over the entire frequency bands with less noise.
摘要:
A magnetic recording medium which comprises a base and a magnetic layer of a magnetic coating composition comprising magnetic particles and a binder provided on said base, characterized in that the magnetic coating composition further comprises a dialkylsulfosuccinate.
摘要:
A hard disk drive (HDD) according to an embodiment of the present invention uses three primary defect map (PDM) formats: a single-sector entry format; a multi-sector entry format; and a two-dimensional sector entry format. Methods of registering defective sectors in each such format are illustrated. Defects can be appropriately registered in a limited RAM capacity by selecting an appropriate format according to states of the defects on a magnetic disk.
摘要:
Embodiments of the invention provide a disk drive capable of preventing the deterioration of performance. In one embodiment, a disk drive includes a disk medium; a head capable of performing a read/write operation for accessing the disk medium to read information from and to write information to the disk medium; a head controller for controlling the position of the head so that the head describes a substantially spiral trajectory relative to the disk medium; and a controller capable of controlling the head controller, of performing a read/write operation for reading or writing information with reference to an identifier table associating sector identifiers identifying sectors on a specified track with logical block addresses, and of creating an identifier table for a track to be accessed next during the read/write operation.
摘要:
A disk drive has an error recovery procedure with a plurality of ERP steps. An unused capacity of an alternate area on a disk for reassigning data is determined. While executing the error recovery procedure, an execution condition for reassigning data is changed based unused capacity of the alternate area. Data is reassigned to the alternate area in response to the execution condition. This prevents the early loss of the alternate area.