Abstract: A disk device for performing error-correction processing is loaded with a high-reliability disk to which a C1 code as a low-level error-correction code (ECC) is added for every sector, and a C2 code as a high-level ECC is added for every plurality of sectors. A host computer includes a device driver corresponding to the high-reliability disk. When data written to the high-reliability disk is read, low-level error-correction is performed based on the C1 code in units of one block corresponding to one sector, and the corrected data is notified to the host computer. Simultaneously, the C2 code along with the data for a plurality of blocks is loaded, and high-level error correction based on the C2 code is thereby performed.

Abstract: In a recording/reproducing apparatus, the controller has a function of increasing a count of incoming head move request pulses by one each time a head move request pulse is supplied while decreasing the count by one each time the magnetic head is moved over one data track by the magnetic head drive to provide a present count, and control the magnetic head drive to move the magnetic head at a speed based on the present count to a desired data track. Also, the magnetic head can also be moved over successive data tracks to a desired data track with a high accuracy.

Abstract: A disk device having access to a disk in different writing modes includes a host PC. The host PC sends a command including a data transfer rate to a controller (disk drive). When the command designating the data transfer rate is received, the writing mode employed for writing data to a disk is automatically switched. The host PC already has the transfer rate to be sent. It is unnecessary to newly prepare a special command to notify the controller in order for switching between the writing modes. Therefore, versatility will not be impaired.

Abstract: In a servo area SA on a track that is empty of data and that lies outside a user data read/write area, to and from which a user data of a floppy disc is written and read, format information FI of the floppy disc is recorded. The format information FI is recorded along with a track number TN in a gray code area GA in the servo area SA. Thereby, the format of the floppy disc can be identified with no identification hole or the like formed in an envelope encasing the floppy disc.

Abstract: In a servo area SA on an empty track outside a user data read/write area to and from which a user data of a floppy disc is written and read, a format information FI of the floppy disc is recorded. The format information FI is recorded along with a track number TN in a gray code area GA in the servo area SA. Thereby, the format of the floppy disc can be identified with no identification hole or the like formed in an envelope encasing the floppy disc.

Abstract: A disc-shaped recording medium for magnetically recording information signals, in which logical block addresses are associated with the recording tracks on the disc in such a sequence in which the logical block addresses proceed in a recordable information area towards the outer rim side, with a first recording track at a mid portion between the innermost recording track and the outermost recording track on the lower disc surface as a logical starting point, until reaching a second recording track, the logical block addresses then proceeding from a third recording track at a mid portion between the innermost recording track and the outermost recording track on the upper disc surface towards the inner rim side as far as a fourth recording track, the logical block addresses then proceeding towards the outer rim side from the next recording track of the second recording track on the lower disc surface lying towards the outer rim side, as far as the outermost recording track on the lower disc surface, the logical

Abstract: Information signals recorded in a signal recording area of a magnetic disk 100 are reproduced for each sector unit by a magnetic head 3, and are taken out through an equalizer 8, an ECC circuit 9 and a buffer 10. A control circuit 12 obtains an estimate value indicating the difficulty of reproduction with respect to operation for reproducing the information signals from the magnetic disk 100, and accumulates the estimate value obtained until the information signals can be correctly reproduced. When the accumulated estimate value has become a predetermined value or greater, the control circuit 12 carried out control to record the information recorded in the corresponding sector into another sector. Thus, generation of such a state that the information signals cannot be reproduced in the future can be prevented.

Abstract: A recording medium driving method and apparatus for recording data on a write-once recording medium, in which it can be checked whether a write-once optical disc is an original disc or a copy disc which has copied digital disc reproduced from an original disc in order to take advantage of the ability of the write-once optical disc as an evidence. The recording medium driving method includes a time information generating step (step ST2) of generating the time information the value of which is changed with lapse of time, a recording data generating step (step ST4) of generating recording data from digital data and the time information and a data recording step (step ST7) of recording the recording data on a write-once recording medium.

Abstract: When recording and/or reproducing data on a disk formatted in a constant linear velocity (CLV) system while the disk is rotated and a head is movable for scanning radially successive circular tracks thereon, and a recording and/or reproducing circuit is operable in response to a data transfer clock for causing the head to record and/or reproduce data in the tracks scanned thereby: the disk is virtually divided into a plurality of virtual zones each comprised of a respective plurality of the tracks; the frequency of the data transfer clock is determined in dependence on the one of the virtual zones in which the tracks being scanned are situated at least during the initiation of a recording or reproducing operation, with the frequency determined at the initiation of a recording or reproducing operation being increased step wise for each successive zone considered in the radially outward direction and being maintained substantially constant at least so long as the tracks being scanned are in the one of the zones

Abstract: In a VTR having a rotary transducer for scanning parallel tracks on a record medium in which signal information is recorded and being displaced at a skew angle with respect to the direction of travel of the record medium, an electromechanical adjustable transducer support, preferably of a piezo-ceramic material supports the transducer for displacement transversely with respect to the parallel tracks in response to a drive signal, and an open loop servo circuit is provided for generating the drive signal to align the scanning path of the transducer with one of the parallel tracks.