摘要:
An apparatus and associated method for detecting head collision with disc media, or other matter, during a write operation is disclosed. The method and apparatus generally monitor the resistance of an MR element on the head in order to detect a temperature increases indicative of a head collision. The resistance can be compared to a pre-selected threshold to generate an output indicative of head collision.
摘要:
In one embodiment of the present invention, systems and methods are provided through which the capacity of a defect buffer in a microcontroller of a mass storage device is determined without regard for the quantity of defects on a recording medium. The capacity of the defect buffer is determined in varying examples, based on the amount of available buffer space and/or the application of the storage device. In one embodiment, the capacity of the defect buffer is less than the quantity of defects on the recording medium, wherein entries in a defect table on the recording medium are swapped in and out of the defect buffer as needed, such as using a most-recently-used scheme. In another embodiment of the present invention, systems and methods are provided through which the defect table is partitioned into a plurality of segments that are physically distributed throughout the recording medium.
摘要:
A disc drive includes a base and a disc rotatably attached to the base. The disc drive also includes a defect management system for managing defective sectors located on the disc surface of a disc within the disc drive. The defect management system includes a controller, and a memory associated with said controller. The controller skips at least a first defective sector and a second defective sector. The first defective sector may be contiguous with the second defective sector or at least one writable sector is located between the first defective sector and the second defective sector. The controller also controls the head to write at least the last two sectors of the plurality of sectors to be written to at least two contiguous sectors located in a pool of spare sectors. A method for writing a plurality of sectors of information to a storage surface on a disc in a disc drive includes determining the start location for writing the plurality of sectors; and determining a number of skipped defective sectors that will be encountered when writing the plurality of sectors. At least two sectors of the plurality of sectors are reassigned and written to at least two sectors in a spare sector pool. The method includes storing the location of the spare sectors within the spare sector pool so that the spare sectors may be located at a subsequent time during a read operation.
摘要:
According to one embodiment of the present invention a disc controller in a disc drive includes a cache memory and a control circuit. The control circuit is configured to identify an operating system of a host computer coupled to the disc drive, select a segmentation level for the cache memory based on the identified operating system, and store information in the cache memory according to the segmentation level. According to another embodiment of the present invention a cache memory in a disc drive is operated by identifying an operating system of a host computer coupled to the disc drive, selecting a segmentation level for the cache memory based on the identified operating system, and storing information in the cache memory according to the segmentation level. The operating system is identified by reading a partition type from a master boot record stored in a disc in the disc drive.
摘要:
True random numbers are generated from position error signals or like signals. The generator is not dependent on a potentially biased reference or threshold, and is capable of quickly generating true random numbers on demand. The present invention can be implemented as an integral functionality of a data storage device to control access to data stored in the data storage device. It can also be implemented in data storage devices for controlling access to host systems or host devices associated with the data storage devices.
摘要:
A data streaming has a data storage device that provides an intermittent data stream to a buffer circuit. The data storage device generates a variable time-to-fill estimate as a function of a sensor output from an environment sensor. The buffer circuit provides a buffer data stream and a time-to-exhaust estimate. A comparator receives the time-to-fill and time-to-exhaust estimates and generates a comparator output. The comparator output couples to the data storage device to control energization of the data storage device.
摘要:
Method and apparatus for generating a random number, such as for use in a security protocol to control access to a data processing system. A processor generates the random number in relation to a back electromotive force (BEMF) value. The BEMF value is preferably obtained in response to application of current to a circuit. The circuit preferably comprises a coil and the application of current preferably induces a relatively small movement of the coil. The random number is preferably a multi-bit digital value, and each bit of the random number is determined in relation to whether the corresponding BEMF value is even or odd. The coil preferably comprises a coil of a voice coil motor (VCM) used to position a transducer adjacent a rotatable storage medium, and the random number is preferably generated while the medium is in a non-rotatable state.
摘要:
In one illustrative example, a bridge connecting a universal serial bus (USB) interface and an advanced technology attachment (ATA) interface may decode a customized small computer system interface (SCSI) command to enable the system to send ATA commands over the USB interface. A customized SCSI command may implement a “pass-through” feature that allows the system to support logical block addresses (LBA) of 48 or more bits, and Self-Monitoring and Reporting Technology (SMART) commands associated with a hard disc drive (HDD). In conjunction with the bridge, the system may send an ATA-command payload, within a wrapper. The bridge may remove the wrapper without substantially altering the payload, and send the ATA-command payload over the ATA bus.
摘要:
A method to improve drive read performance in a disc drive includes powering-up a disk drive, reading reassigned sectors data from a reassign spare pool, and storing the reassigned sectors data in a reassigned cache segment. This method also includes initiating a read request, detecting a reassigned sector within the read request, and determining whether the requested sector can be located in the reassignment cache. If the reassigned sectors are found in the cache, then the method includes transferring the reassigned sector data from the reassignment cache to the read buffer or directly to the requesting host computer. If the reassigned sectors are not found in the cache, then the method includes seeking to the reassignment spare pool to fetch as much reassigned sectors data as the reassignment cache can hold. In another embodiment, the reassigned sectors data stored in a reassignment cache segment is located in a buffer.
摘要:
A method and apparatus for reducing retry redundancy during disc read operations in a disc drive system are provided in which a number of physical sectors to be read from the disc during read operations is first determined. An attempt is then made to read all sectors of the number of sectors during a first disc revolution. Failed sectors of the number of sectors during the first disc revolution are also identified. A retry cycle is then performed on the failed sectors during a second disc revolution following the completion of the attempt to read all sectors of the number of sectors during the first revolution.