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:
The present invention provides a method of describing defects that requires less memory space than conventional methods. Entries of a first defect table are sorted according to the type of track layout, or zones. They are then grouped into clusters. Each cluster is characterized by a set of new parameters, including a starting sector, a scratch parameter, a span parameter, and an angle parameter. The new parameters are stored in a second table, replacing the corresponding entries in the first table. In this manner, a single entry in the second table replaces one or more entries in the first table with one entry in the first table.
摘要:
A method of storing values that involves splitting each value into a n-bit value and an overflow value, and storing, in a main table, the n-bit values in order of increasing magnitude of the values. For each overflow value, the position of the smallest n-bit value is stored in an overflow table. To retrieve a value, the position of the corresponding n-bit value is compared to the positions stored in the overflow value to determine the overflow value of the n-bit value. The actual value is then obtained from the n-bit value and its overflow value.
摘要:
A method of and apparatus for generating a reader-to-writer offset for a head positioned over a track on a disc in a disc drive having a plurality of tracks is disclosed. A reader and a writer are mounted on the head in a non-overlapping manner with a gap between the reader and the writer, which is known as the reader-to-writer offset. A disc drive controller is operably connected to the reader and the writer. The disc drive controller determines the reader-to-writer offset of the head for each track by computing the difference between a first head position x1 and a second head position x2. The first head position x1 is an optimal head position for writing information on the track and the second head position x2 is a midpoint of an off-track capability (OTC) of the head. The OTC is a portion of a track pitch over which the reader is expected to read information that is free of an incorrigible bit error such that the writer-to-reader track misregistration (TMR) is minimized as the head is radially displaced the reader-to-writer offset to read information written on the track or to write information on the track.
摘要:
An apparatus and method of predicting functional capability of a data storage device having a plurality of information tracks, comprising performing a DC erase on three adjacent information tracks, writing a predetermined bit pattern on a middle track of the three adjacent information tracks, providing a first signal from the bit pattern to a variable gain amplifier to generate a first value of the variable gain amplifier, performing DC erases on the information tracks adjacent the middle track, reading the bit pattern from the middle track to provide a second signal to the variable gain amplifier to generate a second value of the variable gain amplifier, and operating on the first and second values of the variable gain amplifier to provide a track mis-registration value for use with a predetermined threshold value to determine the functional capability of the data storage device.
摘要:
A method of, apparatus for, and means for controlling pitch of a servowritten track on a disc in a disc drive are disclosed. The disc drive has a head for traversing over a surface of the disc. The head has a read element and a write element separated by a head element offset &Dgr;. A servowriting controller operably connected to the disc drive creates a track k by writing servo information on the disc. The servowriting controller then calculates the head element offset &Dgr; at the track k, [&Dgr;CALC(k)] and determines a skew angle &thgr; at the track k, [&thgr;(k)]. The servowriting controller adjusts a track pitch correction factor based on the &Dgr;CALC(K) and the &thgr;(k) such that the track pitch correction factor is utilized to servowrite a next track.