摘要:
A measurement circuit is provided to obtain data for monitoring the quality of performance from a digital read channel. Elements of the digital read channel including a sequence detector are incorporated into an integrated circuit together with the measurement circuit. The measurement circuit relates digitized samples of readback data from a magnetic storage device to surrounding samples so that particular samples can be collected in accordance with their surroundings. The circuit includes a programmable time window which can be repeatedly opened for data collection. The circuit is designed to collect various types of data including the bit error rate, sample value, squared sample error, squared gain error, squared timing error, and the occurrences of sample error when it is outside an acceptable programmable threshold. The measurement circuit includes a signal generator for producing a test pattern that is first stored and then read to produce the digitized readback sample values. The measurement circuit also includes a conversion circuit for converting the test pattern to a sequence of expected sample values in accordance with a state machine model of the sequence detector. The sample value error results from a comparison of the readback sample value to the expected sample value.
摘要:
A channel quality circuit, incorporated within a sampled amplitude read channel utilized in a magnetic storage system, for processing and accumulating performance data from the individual read channel components, wherein the performance data is used to calibrate the read channel to operate in a particular environment, to estimate the bit error rate of the storage system, and to detect defects in the magnetic medium. The channel quality circuit generates a test pattern of digital data which is written to the storage system. Then, as the test pattern is read from the storage system, the channel quality circuit accumulates performance data from the read channel components. The test pattern is used to generate expected samples and expected sample errors relative to the samples read by the read channel. Gating logic is programmed to accumulate only the particular performance data of interest. The channel quality circuit computes auto and cross-correlations, squared errors, and threshold comparisons. A defect detection filter detects particular defects in the media. In order to predict the bit error rate of the storage system, the channel quality circuit accumulates noise auto-correlation data, confidence metrics from a sequence detector, and cross-correlation of expected sample errors with actual sample errors.
摘要:
A channel quality circuit, incorporated within a sampled amplitude read channel utilized in a magnetic storage system, for processing and accumulating performance data from the individual read channel components, wherein the performance data is used to calibrate the read channel to operate in a particular environment, to estimate the bit error rate of the storage system, and to detect defects in the magnetic medium. The channel quality circuit generates a test pattern of digital data which is written to the storage system. Then, as the test pattern is read from the storage system, the channel quality circuit accumulates performance data from the read channel components. The test pattern is used to generate expected samples and expected sample errors relative to the samples read by the read channel. Gating logic is programmed to accumulate only the particular performance data of interest. The channel quality circuit computes auto and cross-correlations, squared errors, and threshold comparisons. A defect detection filter detects particular defects in the media. In order to predict the bit error rate of the storage system, the channel quality circuit accumulates noise auto-correlation data, confidence metrics from a sequence detector, and cross-correlation of expected sample errors with actual sample errors.
摘要:
A channel quality circuit, incorporated within a sampled amplitude read channel utilized in a magnetic storage system, for processing and accumulating performance data from the individual read channel components, wherein the performance data is used to calibrate the read channel to operate in a particular environment, to estimate the bit error rate of the storage system, and to detect defects in the magnetic medium. The channel quality circuit generates a test pattern of digital data which is written to the storage system. Then, as the test pattern is read from the storage system, the channel quality circuit accumulates performance data from the read channel components. The test pattern is used to generate expected samples and expected sample errors relative to the samples read by the read channel. Gating logic is programmed to accumulate only the particular performance data of interest. The channel quality circuit computes auto and cross-correlations, squared errors, and threshold comparisons. A defect detection filter detects particular defects in the media. In order to predict the bit error rate of the storage system, the channel quality circuit accumulates noise auto-correlation data, confidence metrics from a sequence detector, and cross-correlation of expected sample errors with actual sample errors.
摘要:
In a computer disk storage system for recording binary data, a sampled amplitude read channel comprises a sampling device for asynchronously sampling pulses in an analog read signal from a read head positioned over a disk storage medium, interpolated timing recovery for generating synchronous sample values, and a sequence detector for detecting the binary data from the synchronous sample values. The sequence detector comprises a demodulator for detecting a preliminary binary sequence which may contain bit errors, a remodulator for remodulating to estimated sample values, a means for generating sample error values, an error pattern detector for detecting the bit errors, an error detection validator, and an error corrector for correcting the bit errors. The remodulator comprises a partial erasure circuit which compensates for the non-linear reduction in amplitude of a primary pulse caused by secondary pulses located near the primary pulse. The error pattern detector comprises a peak error pattern detector and, if an error pattern is detected, a means for disabling the error pattern detector until the detected error pattern has been fully processed. The error detection validator checks the validity of a detected error event and, if valid, enables operation of the error corrector.
摘要:
The present disclosure relates to methods, software, and apparatuses for correcting reading and/or writing operations in an optical storage medium. The methods generally include reading a region of an optical storage medium to produce a readback signal, measuring timing offsets for a plurality of the data edges (including one or more non-guide edges), and storing an offset correction for at least one of the plurality of edges based on a measured offset of at least one of the plurality of edges relative to a predetermined offset. The disclosure advantageously enables precise measurement of timing offsets in optical storage media and correction of the measured offsets for timing offsets attributable to edge jitter, timing loop drift, or factors independent of variations in the medium and/or write operation characteristics.
摘要:
Methods, software, and apparatuses for reading from and/or writing to an optical storage medium. The methods generally include steps for reading a region of an optical storage medium to produce a readback signal, processing predetermined pattern data to produce one or more measurement instructions, measuring one or more characteristics of the readback signal in response to the measurement instructions to produce one or more measurement results, and further processing the readback signal in accordance with one or more of the measurement results. Thus, the ability to flexibly set test parameters and to quickly and accurately test the write characteristics of a recordable or re-writable optical storage medium is provided.
摘要:
An integrated data storage control system provides, in a single integrated circuit, RDC, servo logic, ATA interface, microprocessor, and other formerly discrete components in one highly integrated system design. The integrated circuit is rendered using a single integrated circuit technology type (e.g., digital CMOS) for all components. Analog and digital circuits are combined in such a way as to eliminate or reduce noise or interference in digital circuits from analog circuit components. Individual elements may have their outputs and inputs MUXed together such that individual elements can be selectively switched (during testing modes) such that the integrated circuit emulates or behaves in the same or similar manner as one of the prior art components. The present invention may be applied to magnetic hard disk drives (HDDs) or other types of storage devices such as floppy disk controllers, optical disk drives (e.g., CD-ROMs and the like), tape drives, and other data storage devices.
摘要:
An integrated data storage control system provides, in a single integrated circuit, RDC, servo logic, ATA interface, microprocessor, and other formerly discrete components in one highly integrated system design. The integrated circuit is rendered using a single integrated circuit technology type (e.g., digital CMOS) for all components. Analog and digital circuits are combined in such a way as to eliminate or reduce noise or interference in digital circuits from analog circuit components. Individual elements may have their outputs and inputs MUXed together such that individual elements can be selectively switched (during testing modes) such that the integrated circuit emulates or behaves in the same or similar manner as one of the prior art components. The present invention may be applied to magnetic hard disk drives (HDDs) or other types of storage devices such as floppy disk controllers, optical disk drives (e.g., CD-ROMs and the like), tape drives, and other data storage devices.
摘要:
An integrated HDD system provides, in a single integrated circuit, RDC, servo logic, ATA interface, microprocessor, and other formerly discrete components in one highly integrated system design. The integrated circuit is rendered using a single integrated circuit technology type (e.g. digital CMOS) for all components. Analog and digital circuits are combined in such a way as to eliminate or reduce noise or interference in digital circuits from analog circuit components. The invention takes advantage of existing circuit design modules provided in the integrated circuit as “hard block” components which are unchanged by integrated circuit design software. Changes in operability of the overall integrated circuit may be readily achieved by altering “soft block” components to customize or tailor the design for a particular hard drive. Individual elements may have their outputs and inputs MUXed together such that individual elements can be selectively switched (during testing modes) such that the integrated circuit emulates or behaves in the same or similar manner as one of the prior art components.