Abstract: This invention is directed to a method and a circuit for determining a relative phase shift between a data transition and a data separator window which are used to decode data read back from a mass storage device. The data separator windows provide a time interval in which a data transition must occur in order to be properly interpreted. This is accomplished by delaying the occurrence of the data transition, thereby shifting it toward the trailing edge of the data separator window, to determine if the delayed data transition occurs late within the data separator window. At the same time, the occurrence of the data separator window is delayed, thereby shifting the leading edge of the data separator window toward the data transition, to determine if the data transition occurs late within the data separator window.

Abstract: An automatic track follower (ATF) system for accurately positioning the read/write head on the tracks of a magnetic tape comprises a pilot signal generator for generating pilot signals from tape pilot marks; a sample-and-hold circuit for sampling the pilot signals from the tracks immediately adjacent a track being read; a comparator for comparing the magnitudes of the pilot signals from adjacent tracks on both sides of the track being read; a correction circuit for centering the read/write head on the track being read; and a processor for digitally controlling the generator, sample-and-hold circuit, comparator, and correction circuit and their functions, the digital control being under programmable control. Three code bit fields are discriminated from the digital data to detect the beginning of the ATF field on the tape to derive the ATF logic, timing, and control functions.

Abstract: In accordance with the present invention, a method of intelligently organizing a magnetic storage medium is provided. The magnetic storage medium has free space and a plurality of files distributed on it. The plurality of files includes volatile files created within a first predetermined period of time. First, the free space is substantially consolidated on the magnetic storage medium. Then, the volatile files are substantially positioned contiguous to the consolidated free space.

Abstract: A process of scanning and evaluating binary data stored on a magnetic track of a magnetic storage card includes a calibration at the beginning of the scanning operation with certain information stored on the card and a determination of a calibrated time interval. A time curve of the output signal in the calibrated time interval is registered and compared to predefined curve patterns in order to determine deviation of the registered time curve from the curve patterns. A curve pattern showing a least deviation from the registered time curve is identified. The curve pattern may be selected on the basis of information obtained from a previously determined output signal curve. Also, the extreme values are detected to obtain information stored on the card.

Abstract: A digital recording system utilizing a magnetoresistive transducer in a magnetic recording head. The system measures the amplitude of an output signal, E.sub.o, from the transducer for various bias currents as a recorded magnetic media passes by the head. The system then determines the bias current for which the output signal, E.sub.o, is maximized and multiplies that bias current by a suitable factor. The system then operates at the calculated bias current level, thereby minimizing the error rate of the system.

Abstract: Compressed audio signal data are recorded on a CD-ROM disc at a data transfer rate higher than the standard rate. Information indicating the increased data transfer rate is recorded on the disc, and the compressed audio signal data as recorded are interleaved on the disc in accordance with; the increased data transfer rate.

Abstract: A peak detector for detecting accurate peaks of pulses recovered from a magnetic disk in the presence of residual magnetism by a magnetic head, but without the deleterious effects of such residual magnetism. The head supplies differential pulses as respective pulse trains to first and second peak detectors, respectively. The peaks detected in the first train of differential pulses are combined with the peaks detected in the second train, and an output signal produced as a function of the combined peaks is indicative of the pulse peaks. The respective peaks, which represent the positive and negative peaks of the pulses, are compared to a set of reference levels and, depending upon the relationship of those peaks with the reference levels, a gain error or an offset error is indicated. If the positive pulse peaks and negative pulse peaks exhibit substantially similar relationships with respect to the reference levels, a gain error is indicated.

Abstract: Information bearing signals are recorded in one of a plurality of record formats on one record medium, such as a magnetic tape, magnetic disk, optical disk, and the like. The format selected may be commanded or based upon record lengths, in bytes. When the record length equals or exceeds a predetermined number of bytes, then one record is recorded in each signal block of the record format. When the record length is less than the predetermined number, then a second format is used which inserts several of the records in one of the signal blocks. The signal block and its packets respectively contain indications of formats such that any one of several formats may be used on one record medium and in one signal block having a plurality of variable length packets. Logical indicators, such as format marks, tape marks, and the like, may separate formats used on the storage medium.

Abstract: If information is to be recorded on and reproduced from a recording medium in correspondence between a code train in the form of a run-length-limited code and the positions of the leading edge and the trailing edge data of a status transition pattern such as pits, recording domains, a sync signal is inserted at regular intervals in the information converted in the form of the run-length-limited code. The sync signal is constituted by a code train capable of deciding that the sync signal includes a code not existing in the conversion rule into a run-length-limited code during reproduction using a leading edge data or trailing edge data relative to the transition pattern.

Abstract: In step S1, the capacity of the area (remaining quantity) of a disk in which information can be recorded is read, and the remaining quantity is displayed in step S2. After a user inputs the recording time of information to be recorded and the recording capacity w for the recording, an average transmission rate R.sub.1 is calculated from expression R.sub.1 =w/t-.alpha. in step S4. The rate .alpha. is the transmission rate for transmitting signals other than a video signal, such as an audio signal, attached to the video signal. Data obtained by applying a DCT treatment to the video data is quantized with a quantization width corresponding to the average transmission rate R.sub.1 and this data is intermittently recorded on the disk.

Abstract: A data recorder includes a recording unit for recording data having a predetermined data format and a frame address in a recording medium in units of frames each consisting of predetermined amount of data, and for forming a plurality of Partitions each consisting of a plurality of data areas in which different types of data are recorded during recording. The data recorder performs initialization of a length of at least one of the Partitions.

Abstract: A magnetic disk drive apparatus can reduce the production probability of failed sector due to the fact the a decoding start synchronization mark can not be detected in reproduction of data on a magnetic disk and can utilizes the capability of an error correction circuit sufficiently. A plurality of decoding start synchronization marks are provided in each sector of the magnetic disk and when any one of the decoding start synchronization marks can be detected, a decoding circuit can be operated.

Abstract: In accordance with the duplication of bit-patterns on a recording medium of the present invention, presence of gaps as defined by one or more words of predetermined code in data is judged, then with having these gaps as the write-succession points, and placing an unwritable bit-pattern in these respective gaps, data is written in onto the recording medium of the transfer-destination. Thus, the write-succession points can be determined, and the occurrence of bit-shift can be avoided. In addition, transmission of data on the recording media over a long distance become possible.

Abstract: An arrangement (60) for recording an analog signal in a track on a record carrier (82) is provided with an overload detection circuit (78) for detection an overload situation for the analog signal applied to the arrangement. Upon detection of an overload situation, the recording mode is terminated and the record carrier is rewound to the start location of the current recording. Further, the arrangement is provided with a variable attenuator (66). The variable attenuation factor in the attenuator is increased upon detection of the overload situation.

Abstract: An apparatus for damping the ringing effects across the output terminals of a read/write circuit during write operation is described. The present invention introduces a first continuous damping resistance across the inductive load of the read/write head during the write operation, and automatically removes the damping resistance during the read operation. The circuit of the present invention also allows for a second damping resistance suitable for read mode attenuation to be placed directly across the output terminals. The equivalent damping resistance during the write mode is then the resistance of the second damping resistor in parallel with the resistance of the first damping resistor. The damping resistance causes exponential damping of the ringing signal elements, thereby reducing the settling time of the circuit and increasing the operating frequency range.

Abstract: An apparatus and method for generating an index pulse by a data storage tape drive. The tape drive is controlled by a flexible disk controller. A multi-track tape is formatted into multiple data segments per track with erased areas between segments. A digital data signal from the tape signal processor is sampled to detect a lapse in data. Then, the analog data signal is continuously monitored to detect the reappearance of data. When filtered analog signal peaks exceed a fixed threshold, a pulse is generated from the tape drive to the flexible disk controller. In an alternative embodiment, to further protect against false triggering, index pulse generation is suppressed during most of each erased area between segments. In another embodiment, index pulse generation is suppressed if an erased area exceeds a length threshold, such as at the end of the tape. In still another embodiment, index pulse generation is suppressed if digital data reappears without triggering the analog monitoring circuit.

Abstract: A system and method for calibrating amplifier gain and a comparator threshold for use in verification of magnetic media integrity in a magnetic data storage device. Commercially available read data processors are used which have an amplifier with controllable gain and a comparator with an internal indirectly-controllable threshold. An on-board voltage reference is provided for gain calibration. The calibrated gain is used to provide signals with known peak values for calibrating the comparator threshold. In one embodiment, the numeric control value for the threshold is reduced from a calibrated peak value to a specified fraction for media verification. In a second embodiment, the gain is reduced to the industry specified fraction and the threshold is calibrated to match peak signal magnitudes at the reduced gain. The gain is then returned to the calibrated level for media verification.

Abstract: In a rotary head type recording and/or reproducing apparatus having an n number (n: an integer at least 3) of rotary heads for recording or reproducing signals on or from a recording medium, when the recording medium is allowed to travel at a first speed, a signal is recorded or reproduced by using all the n number of rotary heads. When the recording medium is allowed to travel at a second speed which is lower than the first speed, a signal is recorded or reproduced by using only a predetermined m number (m: an integer at least 2 but not exceeding n) of adjacent heads. A distance on the recording medium between tracing positions of adjacent heads included in the predetermined m number of heads when the medium is traveling at the first speed differs from a distance on the recording medium between tracing positions of other adjacent heads included in the n number of rotary heads.

Abstract: A flexible magnetic disc drive apparatus is provided in which access efficiency to a flexible magnetic disc is improved, and which enables rewriting alternate information in the case of alternate registration and allows access even if there is a defect in an ID field.

Abstract: A magnetic record readout circuit and a magnetic recording apparatus. A transistor is located at the output side of a comparator for level slice. If the level slice comparator does not output high for the predetermined time or longer, the transistor remains on. A capacitor is placed between the collector of the transistor and ground. When the transistor is off, the capacitor is charged with a current source connected to the transistor collector. When the capacitor is charged, the level slice comparator outputs high. In response to the level slice comparator which outputs high, one of full-wave rectifying circuits located at the input side of the level slice comparator forces a capacitor for peak hold of a full-wave-rectified waveform to be discharged. As the capacitor is discharged, a given slice level lowers.