Abstract: A disk drive apparatus mounting socket includes a socket portion which supports a disk drive apparatus, a lead portion which is connected to the disk drive apparatus supported by the socket portion, and a terminal unit which is electrically connected to the lead portion and to circuits on a board. A disk drive apparatus, which is connectable to an information processing unit, includes a connecting unit which connects the disk drive apparatus to the information processing unit, and an interface unit which controls the disk drive apparatus in response to a control signal, a data bus signal, and an address bus signal which are generated by the information processing unit and are inputted to the disk drive apparatus from the information processing unit via the connecting unit.

Abstract: A control method which is used in a RAID1 storage subsystem including a plurality of storage devices, and processes an access request from a host computer with the cooperation of the plurality of storage devices of the storage subsystem is provided. In the storage subsystem, each storage device of the RAID1 storage subsystem includes a unit for sharing an access request from the host computer, and a unit for determining if the storage device should process the shared access request. The storage device further includes a unit for transferring write data, which is transmitted from the host computer to the storage subsystem, to at least a storage device that should process it.

Abstract: A disk drive apparatus mounting socket includes a socket portion which supports a disk drive apparatus, a lead portion which is connected to the disk drive apparatus supported by the socket portion, and a terminal unit which is electrically connected to the lead portion and to circuits on a board. A disk drive apparatus, which is connectable to an information processing unit, includes a connecting unit which connects the disk drive apparatus to the information processing unit, and an interface unit which controls the disk drive apparatus in response to a control signal, a data bus signal, and an address bus signal which are generated by the information processing unit and are inputted to the disk drive apparatus from the information processing unit via the connecting unit.

Abstract: A disk drive apparatus mounting socket includes a socket portion which supports a disk drive apparatus, a lead portion which is connected to the disk drive apparatus supported by the socket portion, and a terminal unit which is electrically connected to the lead portion and to circuits on a board. A disk drive apparatus, which is connectable to an information processing unit, includes a connecting unit which connects the disk drive apparatus to the information processing unit, and an interface unit which controls the disk drive apparatus in response to a control signal, a data bus signal, and an address bus signal which are generated by the information processing unit and are inputted to the disk drive apparatus from the information processing unit via the connecting unit.

Abstract: A magnetic recording and reproducing apparatus includes a R/W signal processor having a write data generator arranged to be of an interleave system and transmitting/receiving data to/from the R/W amplifier via a plurality of signal lines. In addition, the R/W amplifier has a compound circuit provided for the write data of the interleave system from the R/W signal processor and is formed as an integrated circuit, moreover, a ½ prescaler is provided at the output of the write data generator, making transmitting and receiving write data in NRZI CODE.

Abstract: A control method which is used in a RAID1 storage subsystem including a plurality of storage devices, and processes an access request from a host computer with the cooperation of the plurality of storage devices of the storage subsystem is provided. In the storage subsystem, each storage device of the RAID1 storage subsystem includes a unit for sharing an access request from the host computer, and a unit for determining if the storage device should process the shared access request. The storage device further includes a unit for transferring write data, which is transmitted from the host computer to the storage subsystem, to at least a storage device that should process it.

Abstract: A magnetic recording and reproducing apparatus includes a R/W signal processor having a write data generator arranged to be of an interleave system and transmitting/receiving data to/from the R/W amplifier via a plurality of signal lines. In addition, the R/W amplifier has a compound circuit provided for the write data of the interleave system from the R/W signal processor and is formed as an integrated circuit, moreover, a ½ prescaler is provided at the output of the write data generator, making transmitting and receiving write data in NRZI CODE.

Abstract: A magnetic recording and reproducing apparatus includes a read/write signal processor having a write data generator arranged to be of an interleave system and transmitting/receiving data to/from the read/write amplifier via a plurality of signal lines. In addition, the read/write amplifier has a compound circuit provided for the write data of the interleave system from the read/write signal processor and is formed as an integrated circuit, moreover, a 1/2 prescaler is provided at the output of the write data generator, transmitting and receiving write data in Non-Return-To-Zero-Interleave CODE.

Abstract: A reproducing apparatus including a reading apparatus for reading signals recorded on a recording medium, a reproducing apparatus for reproducing data from read-out signals from the reading apparatus, an error detector for detecting an error in the data reproduced by the reproducing apparatus, a phase-synchronizing apparatus for synchronizing signals, for the reproducing apparatus, a characteristic changing apparatus for changing reproduction characteristics of the reproducing apparatus of loop characteristics of the phase-synchronizing apparatus, when the error detector detects an error on any one of a track on the recording medium, and a retry apparatus for retrying reading of a track on which the error is detected, under changed reproduction characteristics.

Abstract: A magnetic disk recording and reproducing apparatus comprising a unit for inserting an error correcting code related to control information into said control information on data; a recording control unit for recording in a plurality of sectors formed by dividing the recording area of a magnetic disk, each sector having an ID area for recording said control information and a data area, provided adjacent to and behind said ID area, for recording said data; and a error correcting unit for correcting said control information of said ID area by said error correcting code before data is read from said data area corresponding to said ID area or data is recorded in said data area corresponding to said ID area.

Abstract: A magnetic disk recording and reproducing apparatus comprising a unit for inserting an error correcting code related to control information into said control information on data; a recording control unit for recording in a plurality of sectors formed by dividing the recording area of a magnetic disk, each sector having an ID area for recording said control information and a data area, provided adjacent to and behind said ID area, for recording said data; and a error correcting unit for correcting said control information of said ID area by said error correcting code before data is read from said data area corresponding to said ID area or data is recorded in said data area corresponding to said ID area.

Abstract: A disk storage device includes a data transfer control device for transferring data from a higher rank device to a storage medium and transferring data from the storage medium to the higher rank device, an identification device having identification information for determining whether it should be permitted or inhibited to write data into a predetermined recording area of the storage medium, and a data transfer command device, responsive to a data recording command given by the higher rank device, to order the data transfer control device to write data into the storage medium according to the identification information of the identification device. In response to a data write command given to the storage medium by the higher rank device, the data transfer command device collates a state of the data write command with the identification information possessed by a predetermined sector of the storage medium.

Abstract: A disk drive apparatus mounting socket includes a socket portion which supports a disk drive apparatus, a lead portion which is connected to the disk drive apparatus supported by the socket portion, and a terminal unit which is electrically connected to the lead portion and to circuits on a board. A disk drive apparatus, which is connectable to an information processing unit, includes a connecting unit which connects the disk drive apparatus to the information processing unit, and an interface unit which controls the disk drive apparatus in response to a control signal, a data bus signal, and an address bus signal which are generated by the information processing unit and are inputted to the disk drive apparatus from the information processing unit via the connecting unit.

Abstract: A disk type recording and reproducing apparatus includes a disk type recording medium having a plurality of tracks and having stored on each of the plurality of tracks a position signal indicating positions on the tracks; a drive section for rotating the disk type recording medium; a dual head separately incorporating a reading head for reading from the disk type recording medium and a writing head for writing into the disk type recording medium; a head drive section for moving the dual head; means for controlling the head drive section by a controlled variable in compliance with a position signal read from the disk type recording medium using an object track and the reading head; and memory means for storing quantity information used to correct the controlled variable of the means for controlling the head drive section.

Abstract: A disk drive is mounted to a circuit board by directly connecting a disk drive apparatus with a circuit board by using a DIP, PLCC, QFP, or PGA mounting method. The disk drive apparatus has an interface for controlling a disk drive in response to a control signal, a data bus signal and an address bus signal outputted from an information processing unit so that the disk drive apparatus may be connected like a memory card of the information processing unit.

Abstract: A disk type recording and reproducing apparatus includes a disk type recording medium, and a dual head including a reading head and a writing head. A center of the core of the reading head is shifted in the radial direction of the disk type recording medium relative to a center of the core of the writing head. The disk type recording medium has a plurality of recording tracks each having a plurality of sectors. Each of the sectors has an ID division provided ahead of a data division disposed in the circumferential direction of the disk type recording medium. The ID division has recorded therein identification information identifying the sector. A center line of the ID division is shifted in the radial direction of the disk type recording medium relative to a center line of the data division by a distance equal to a distance by which the center of the core of the reading head is shifted in the radial direction of the disk type recording medium relative to the center of the core of the writing head.

Abstract: The recording and reproducing apparatus comprises an Small Computer System Interface (SCSI) controller, an optical disc device, a magnetic disc device, a disc controller which controls the optical disc device and the magnetic disc device, connectors which connects directly the optical disc device and the magnetic disc device, and a selector which selects one of the optical disc device and the magnetic disc device. A Copy or Verify command is carried out within the apparatus without an SCSI bus, and data are transferred through the connector. Therefore occupation of the SCSI bus and overhead of the SCSI protocol are eliminated, and the apparatus is miniaturized by common use of the SCSI controller and the disc controller.

Abstract: Reproducing apparatus with an A/D (analog-to-digital) converter, which realizes high-accuracy data sampling, high-speed data transfer, low dissipation power and low cost. PR (partial response) processing is performed by receiving encoded signals, delaying the received signals on the basis of a reference clock, and adding the delayed signals and the received signals in analog signal form. The added signals are converted into digital values on the basis of the reference clock by the A/D converter, and Viterbi decoding is performed on the basis of the converted digital values. Owing to the PR processing which is performed at a stage preceding the A/D converter, a frequency band for the A/D conversion can be lowered, and hence, the high-accuracy data sampling is permitted.

Abstract: A magnetic recording and reproducing apparatus such as a disk drive has a phase locked loop circuit which is less susceptible to an effect of noise of a power supply and ground and reduces a clock jitter. The magnetic recording and reproducing apparatus is compatible to a constant density recording system without increasing a circuit scale and a power consumption and with a small number of IC pins. The phase locked loop circuit of the magnetic recording and reproducing apparatus is provided with two D/A converter circuits to drive a loop filter. It is also provided with a circuit for distributing a reference potential of a voltage controlled oscillator (VCO) and a center frequency of the VCO, a gain of the VCO and a current gain of the D/A converter circuit are changed in linked relation. A reference voltage source is provided such that a center point or one end of the loop filter is connected to the reference voltage eliminating the ground connection.

Abstract: A phase lock loop system includes: a phase detecting circuit which operates on the basis of a signal waveform; a current output circuit for generating a current value from a phase difference detected by the phase detecting circuit; a filter which is constructed by only a resistor in a phase locked state by a synchronizing signal and by a capacitor and the resistor upon phase following state; and a voltage controlled oscillator for controlling an oscillation frequency by a voltage output of the filter. The phase lock loop system operates as a primary phase lock loop circuit in the phase locked state by the synchronizing signal and operates as a secondary phase lock loop circuit upon phase following state.