摘要:
Patterned-media magnetic recording disks are made from a master template that has nondata regions that contain a pattern of one or more discrete nondata islands and discrete gaps, with the pattern representing a scrambled number. All disks made from the master template, or from replica molds made from the master, will have the same patterns. When the disks are DC-magnetized so that all the nondata islands are magnetized in the same direction, these patterns will include one or more of discrete magnetized nondata islands and discrete nonmagnetic gaps that are scrambled in a pseudo-random manner. During operation of the disk drive the patterns are detected by the read head and interpreted within the disk drive using knowledge of the pseudo-random scrambling function, so that reading and writing of data can occur in the conventional manner. If the disks are copied in an attempt to replicate the master template, the resulting disks will be inoperable in a disk drive because of the scrambling.
摘要:
Patterned-media magnetic recording disks are made from a master template that has nondata regions that contain a pattern of one or more discrete nondata islands and discrete gaps, with the pattern representing a scrambled number. All disks made from the master template, or from replica molds made from the master, will have the same patterns. When the disks are DC-magnetized so that all the nondata islands are magnetized in the same direction, these patterns will include one or more of discrete magnetized nondata islands and discrete nonmagnetic gaps that are scrambled in a pseudo-random manner. During operation of the disk drive the patterns are detected by the read head and interpreted within the disk drive using knowledge of the pseudo-random scrambling function, so that reading and writing of data can occur in the conventional manner. If the disks are copied in an attempt to replicate the master template, the resulting disks will be inoperable in a disk drive because of the scrambling.
摘要:
Patterned-media magnetic recording disks are made from a master template that has nondata regions that contain a pattern of one or more discrete nondata islands and discrete gaps, with the pattern representing a scrambled number. All disks made from the master template, or from replica molds made from the master, will have the same patterns. When the disks are DC-magnetized so that all the nondata islands are magnetized in the same direction, these patterns will include one or more of discrete magnetized nondata islands and discrete nonmagnetic gaps that are scrambled in a pseudo-random manner. During operation of the disk drive the patterns are detected by the read head and interpreted within the disk drive using knowledge of the pseudo-random scrambling function, so that reading and writing of data can occur in the conventional manner. If the disks are copied in an attempt to replicate the master template, the resulting disks will be inoperable in a disk drive because of the scrambling.
摘要:
Patterned-media magnetic recording disks are made from a master template that has nondata regions that contain a pattern of one or more discrete nondata islands and discrete gaps, with the pattern representing a scrambled number. All disks made from the master template, or from replica molds made from the master, will have the same patterns. When the disks are DC-magnetized so that all the nondata islands are magnetized in the same direction, these patterns will include one or more of discrete magnetized nondata islands and discrete nonmagnetic gaps that are scrambled in a pseudo-random manner. During operation of the disk drive the patterns are detected by the read head and interpreted within the disk drive using knowledge of the pseudo-random scrambling function, so that reading and writing of data can occur in the conventional manner. If the disks are copied in an attempt to replicate the master template, the resulting disks will be inoperable in a disk drive because of the scrambling.
摘要:
Methods and/or systems/apparatus using speech for marking and subsequently identifying one or more items having electronically-readable identifiers respectively marked thereon comprise the following steps and/or perform the following operations. First, at least a portion of the electronically-readable identifier marked on an item is inputted. A user then inputs a spoken utterance that corresponds to the item. Next, the electronically-readable identifier inputted from the item is associated with the spoken utterance input from the user. Thus, when the electronically-readable identifier is inputted a next time, the spoken utterance associated with the electronically-readable identifier may be outputted. The present invention may also be embodied as an article of manufacture comprising a machine readable medium containing one or more programs which when executed implement the steps/operations of the invention.
摘要:
A data recording system, such as a magnetic recording hard disk drive, has a recording medium in which the data tracks have pseudo-random binary sequences for the servo information used to control the position of the recording head. A first pseudo-random binary sequence (PRBS) and a second PRBS identical to the first PRBS but shifted by a portion of the period of the first PRBS are located between the track boundaries in alternating tracks in a first region of the servo pattern and between the track centers in alternating tracks in a second region spaced along the track from said first region. A servo decoder has two correlators, one for each PRBS. Each correlator outputs a dipulse when its PRBS repeats. The difference in amplitude of the dipulses represents the head position signal. The dipulses also control the amplifier for the signal read back by the head and the timing of the track identification (TID) detector.
摘要:
A hard disk drive (HDD) minimizes the effects of far track erasure (FTE) by counting the number of writes to the data tracks and incrementing counters based on the known effect of FTE on each track. The extent of the FTE effect is determined for each track within a range of tracks of the track being written, and based on the relative FTE effect for all the tracks in the range a count increment (CI) is determined for each track within the range. A counter is maintained for each track. For every writing to a track, a count for each track within a range of the track being written is increased by the CI value associated with the track number within the range. When the count value for a track reaches a predetermined threshold the data is read from that track and rewritten, preferably to the same track.
摘要:
Secure data is written to a disk during manufacture in such a way that it can be read but not copied. Methods include writing triangular transitions or very slow transitions from positive magnetic to negative magnetic and then erasing the negative parts to yield a code that consists of positive read back amplitudes only. Or, high frequency transitions can be written during servo writing.
摘要:
A hard disk drive (HDD) minimizes the effects of far track erasure (FTE) by counting the number of writes to the data tracks and incrementing counters based on the known effect of FTE on each track. The extent of the FTE effect is determined for each track within a range of tracks of the track being written, and based on the relative FTE effect for all the tracks in the range a count increment (CI) is determined for each track within the range. A counter is maintained for each track. For every writing to a track, a count for each track within a range of the track being written is increased by the CI value associated with the track number within the range. When the count value for a track reaches a predetermined threshold the data is read from that track and rewritten, preferably to the same track.
摘要:
A data recording medium, such as a magnetic recording hard disk, has data tracks with pseudo-random binary sequences for the servo information used to control the position of the recording head in the disk drive. A first pseudo-random binary sequence (PRBS) and a second PRBS identical to the first PRBS but shifted by a portion of the period of the first PRBS are located between the track boundaries in alternating tracks in a first region of the servo pattern and between the track centers in alternating tracks in a second region spaced along the track from said first region. A servo decoder in the disk drive has two correlators, one for each PRBS. Each correlator outputs a dipulse when its PRBS repeats. The difference in amplitude of the dipulses represents the head position signal. The dipulses also control the amplifier for the signal read back by the head and the timing of the track identification (TID) detector.