Abstract: A disk for a disk drive system includes a disk having a track format region including a spoke field region. The spoke field region has a single binary bit to identify angular position of a track with respect to disk head of the disk drive system.

Abstract: A method and a device for write precompensating a data pattern for recording the pattern on a magnetic storage medium at high data rates. A first predetermined write-precompensation delay is applied to the second transition of a burst of transitions of the data pattern. A second predetermined write-precompensation delay is applied to the last transition of a burst. A third predetermined write-precompensation delay is applied to the middle transitions, if any, of a burst. When the burst is a dibit, the application of the second and third predetermined write-precompensation delays is omitted and the first predetermined write-precompensation delay is based on the burst being a dibit. When the burst is a tribit, the application of the second predetermined write-precompensation delay is omitted and the first and third predetermined write-precompensation delays are based on the burst being a tribit.

Abstract: A method and a mechanism enabling the method are described to aid in distinguishing new information from old information on a medium. A new variable called a Master Write Pass Count is created for the medium. The Master Write Pass Count is initialized once, advanced on each occasion that new information is written in the medium, and it is never reinitialized or regressed. During each write session the Master Write Pass Count is copied into a Write Pass Count variable associated with each block receiving the new information. The Write Pass Counts may be stored in the header or trailer of the associated block, or external to the block. When the blocks are read from the medium, the Write Pass Counts may be used alone, or in combination with other information associated with the blocks, such as a block identification number, to aid in distinguishing new information from old information.

Abstract: A digital signal recording apparatus includes an amble generator for generating an amble signal representing a bit-sequence amble pattern. The bit-sequence amble patter can be detected and reproduced by a partial-response detection system “PR(1, 0, −1)” as a detected amble pattern having a period of state inversions which is shorter than a period of state inversions in a detected amble pattern corresponding to a recorded amble pattern of alternation of “1” and “0”. The amble signal generated by the amble generator and a first digital information signal are combined into a second digital information signal on a time sharing basis. The second digital information signal is recorded on a magnetic recording medium. For example, the bit-sequence amble pattern represented by the amble signal has repetition of six bits of “111000”.

Abstract: In a magnetic disk device, a deterioration of performance caused by an environmental variation is suppressed by utilizing an automatic adaptation function in a read/write channel IC. A gate provides a timing for the automatic adaptation of an equalization coefficient, a signal from the gate is given to a read-gate input terminal of the read/write channel IC, and the gate for the automatic adaptation is opened before reading data from a destination sector to be read. The automatic adaptation is started, whereby coefficients for equalization are adapted to signal wave forms before reading data.

Abstract: In tracking control method and apparatus thereof for an image recorder/reproducer, there are provided a method and device which can accomplish a high-performance tracking control by using the variable capstan speed instruction which is reflected by the degree of tracking error instead of using the conventional capstan speed instruction wherein the tracking error is not reflected. For this, a tracking control method includes the steps of obtaining the degree of tracking control by performing a predetermined gain control on the tracking error, and generating the variable capstan speed instruction wherein the degree of tracking control is reflected, and determining the degree of speed error of capstan motor by comparing the capstan speed instruction with the actual rotation speed of capstan motor, and obtaining the degree of speed control of capstan motor wherein the tracking error is reflected by performing a predetermined gain control on the speed error.

Abstract: The present invention provides a magnetic recording apparatus including a magnetic recording medium and a magneto-resistance effect (MR) element opposing to the magnetic recording medium, so that an information recorded on the magnetic recording medium is reproduced via the MR element, wherein if it is assumed that the MR element has a sheet resistance &rgr;s, the magnetic recording medium has a sheet resistance &rgr;s′, and the magnetic recording medium generates a medium magnetic field having a resistance change ratio P, then the values &rgr;s, &rgr;s′, and P are set to satisfy the relationship as follows: &rgr;s′>&rgr;s/P.

Abstract: A method of managing information to be stored on a storage disc in a disc drive system to achieve improved system performance. Some of the data on the disc may be mirrored on the same surface of the disc to reduce latency and/or seek time. Compression techniques may be employed to limit reductions in the storage capacity of the disc. In another embodiment, data is preferentially stored on the outer tracks of the disc because system performance is greater when accessing outer tracks. Compression techniques may also be employed with this embodiment to limit reductions in the storage capacity of the disc. Compressed data stored on the disc may be transferred to another storage medium in its raw compressed form to reduce the number of instructions that would be required to transfer the data if it were decompressed before transfer.

Abstract: A disk drive includes a disk having a disk surface. The disk surface has a plurality of tracks arranged in an embedded servo format including servo track segments for storing servo data and data track segments for storing user data. Data from the disk surface is read to produce a time-multiplexed analog read signal that during a revolution of the disk represents analog read servo data during each of a first set of time intervals and represents analog read user data during each of a second set of time intervals. The disk drive further includes a controller and a channel integrated circuit chip. The controller includes a controller port. The channel integrated circuit chip includes an input for receiving the time-multiplexed analog read signal. The time-multiplexed analog read signal is processed to generate data symbols representing recovered servo data and recovered user data.

Abstract: A video signal recording apparatus for recording a video signal on a recording medium comprises a memory for temporarily memorizing the video signal, a synchronizing separating circuit for separating a synchronizing signal from the video signal, a write control signal generating circuit for generating a write control signal used to write the video signal in the memory in response to the synchronizing signal from the synchronizing separating circuit, a recording circuit connected to the memory for recording the video signal read out from the memory on the recording medium, a timing signal generator for generating a timing signal relating to a driving state of the recording medium, and a read control signal generating circuit for generating a read control signal used to read the video signal memorized in the memory on the basis of the timing signal.

Abstract: A method of managing information to be stored on a storage disc in a disc drive system to achieve improved system performance. Some of the data on the disc may be mirrored on the same surface of the disc to reduce latency and/or seek time. Compression techniques may be employed to limit reductions in the storage capacity of the disc. In another embodiment, data is preferentially stored on the outer tracks of the disc because system performance is greater when accessing outer tracks. Compression techniques may also be employed with this embodiment to limit reductions in the storage capacity of the disc. Compressed data stored on the disc may be transferred to another storage medium in its raw compressed form to reduce the number of instructions that would be required to transfer the data if it were decompressed before transfer.

Abstract: Disclosed are a method and a detector for adaptively detecting servo gaps in a timing based servo pattern prerecorded on a variable velocity media. The timing based servo pattern has groups of repeated pairs of non-parallel transition stripes arranged in bursts, the bursts separated by servo gaps whose length is variable. A servo system sensor senses the transition stripes in the longitudinal direction of the media. A group interval detector coupled to the sensor detects the timing interval between the same slope transition stripes of two sequential groups of bursts. A divider divides the detected group timing interval by a predetermined divisor to provide a divided timing interval gap detection threshold. A sequential stripe interval detector coupled to the sensor measures the timing interval between stripes, and a comparator compares the divided timing interval and the timing interval, identifying a servo gap upon the measured timing interval at least equaling the gap threshold.

Abstract: A signal detecting device for detecting a pilot signal component from a modulated digital signal which contains information data and the pilot signal component, comprises a digital converter for performing bit-quantization of the modulated digital signal, a detector for detecting the pilot signal component and a restoring circuit for restoring the information data, the detector and the restoring circuit both using an output of the converter. The detecting device is digital throughout since the pilot signal component is detected by using an output of the digital converter.

Abstract: As described above, according to the present invention, original data that is input as records is compressed. The compressed data is temporarily stored in the buffer memory and then recorded on the magnetic tape. When data is recorded, it is determined whether or not the buffer memory overflows. When the determined result represents that the buffer memory overflows, the value of the counter is dynamically changed. Thus, the buffer memory can be prevented from overflowing. The compressed data is recorded as entities and recorded to each group. The BAT flag that represents the type of the entity is added. When data is reproduced, it is determined whether the last entity of the current group is an entity that continues to the next group or an entity that is completed in the current group. When the last entity continues to the next group, the next group is accessed. When the last entity is completed in the current group, no further accessing operation is performed.

Abstract: An apparatus and method for performing real-time, closed loop write verification in a disc drive having a rotatable magnetic disc and a head having read and write elements. During a write operation, the disc drive generates a write current signal indicative of input data to be written to the disc. The write current signal is applied to the write element, which generates a time-varying magnetic field to simultaneously induce a readback signal in the read element through magnetic coupling of the read element to the write element, and to magnetize the disc to write the input data to the disc. The readback signal induced in the read element is used to reconstruct a set of output data which is used to verify accuracy of the input data.

Abstract: A method and apparatus for monitoring the quality of the readback signal of data written on a magnetic recording disk in a disk drive and for limiting data loss due to physical damage at a slider/disk interface. The amplitude of a read signal is continuously monitored in the read channel, either by directly measuring the read signal amplitude or by monitoring the amplification level of the automatic gain control (AGC) circuit in the read channel which is inversely proportional to the read signal amplitude. If the amplitude of the monitored read signal decreases below a chosen level, the location of the data on the disk track is flagged as possibly damaged. The data is rewritten at the same location and then reread to see if full recovery of the degraded data is possible. If the amplitude read signal of the rewritten data is greater than a chosen level, the disk track is judged to be usable and normal operation continues.

Abstract: In a data recording system utilizing multiple channels and data blocks wherein the data blocks are read subsequent to being written so as to check for errors, the data blocks are rewritten according to a method to provide for rewriting only the defective data blocks. The blocks may be rewritten on other than their original channels. Channels for rewriting are determined by selecting a channel with a highest current block number so that data is rewritten in a channel which has been able to write and verify the most of its original blocks. Error checking is continued in a channel even after finding of an error in that channel. Data blocks of the frames may be skewed between the channels at a beginning of the frame. A ring counter output is applied to break a deadlock where a block is continously rewritten on a failing channel.

Abstract: A disk drive includes a disk having a disk surface, the disk surface having a plurality of tracks arranged in an embedded servo format. The disk surface includes a plurality of radially-extending user-data regions and a plurality of radially-extending servo-data regions. Each user-data region has a plurality of data zones in each of which user data are stored in a plurality of track segments at a data channel frequency particular to that data zone. Each servo-data region has a plurality of servo zones in each of which servo data are stored in a plurality of track segments at a servo channel frequency particular to that servo zone. The servo channel frequency differs from the data channel frequency for at least one track.

Abstract: A storage media is disclosed and comprises a storage body and a readable indelible mark formed in the body such that portions thereof are indelibly altered. The mark is read by writing first data to the body in the region of the mark, and reading second data from the body in such region. The written first data is not accepted where the portions of the body are indelibly altered. Accordingly, the read second data corresponds to the written first data with segments thereof missing. The missing segments of the first data correspond to the portions of the body indelibly altered. In a preferred embodiment, the storage media comprises a magnetic rotatable disk having a substantially planar substrate and a magnetizable layer deposited thereon. The reading and writing are therefore performed magnetically.

Abstract: A method and apparatus is disclosed for reducing electrical noise from noise spikes in an electrical information signal. The invention can provide protection of a data storage system from soft errors rate due to noise spikes appearing in the signal from the input transducer. A cancellation signal for the low frequency component (i.e. in the system bandwidth) of the noise signal is generated. The cancellation signal is derived from a frequency band that appears in the noise spike, but does not appear in the system bandwidth for the information signal. The cancellation signal is generated in the preferred embodiment by a cancellation signal generator comprising a high pass filter and a mixer. The mixer generates a cancellation signal by processing the high frequency portion using a waveform above the normal high frequency cutoff to reconstitute the low frequency component of the noise spike in the normal frequency band.