Hitachi, Ltd.

Nippon T&t Corp.

Takashi Doi

Michio Miyazaki

Akira Yamamoto

Masahito Mori

Mikito Ogata

Takashi Kobayashi

Hiroyuki Kitajima

Minoru Kosuge

Kenzo Kurihara

Yuji Yamane

Kenichi Kageura

Masaaki Kobayashi

Masafumi Nozawa

Yoshihiro Uchiyama

Norihisa Komoda

Isao Tsushima

Takafumi Oka

Kenji Tokumitsu

Toshifumi Nishimura

Toru Nishigaki

Katsuharu Kakuse

Nobuyoshi Izawa

Miho Motoyama

Soichi Oyama

Masaru Teranishi

Ai Tanaka

Miho Nonomura

Toru Takeda

An information medium storage and management system includes storage compartments for storing a plurality of information media; a plurality of recording/reproducing apparatus each capable of accessing each of a plurality of information media, each capable of recording at least one file; handling apparatus for mounting a mount information medium on a mount recording/reproducing apparatus and demounting a demount information medium from a demount recording/reproducing apparatus; and a controller for controlling the handling apparatus to select as the mount information medium one of the plurality of information media in accordance with the use history data of each information medium, to select as the mount recording/reproducing apparatus one of unoccupied recording/reproducing apparatus of the plurality of recording/reproducing apparatus, and to cause the mount information medium to use the mount recording/reproducing apparatus for a predetermined time period.

Method and system for storing and managing a plurality of information

A buffered peripheral system comprises a backup memory and a primary control unit which has a buffer memory for temporarily storing a copy of the contents of a buffer memory which stores data to be written to a peripheral device and a control device for issuing a command necessary to write the block stored in the buffer memory device to the peripheral device. The primary control unit also includes a recording device for recording the block number corresponding to the block which was most recently written to the peripheral device. The blocks of data which have been written to the peripheral device is then deleted from the backup memory to make room for storing further blocks of data. The system further has a backup control unit substantially identical to the primary control unit. Only the primary control unit normally operates to control the writing to the peripheral device. Upon detection of the failure of the buffer memory in the primary control unit, the backup control unit completes the operation of writing to the peripheral device by retrieving the blocks of data to be written to the peripheral device from the backup memory device using the block number information.

Buffered peripheral system and method for backing up and retrieving data

A magnetic recording subsystem comprises a channel unit, a magnetic recording control unit having a data buffer for temporarily storing data blocks of data transferred from the channel unit and a plurality of magnetic recording units connected to the magnetic recording control unit. When the data is stored into the data buffer, a block number is assigned to each data block. When the data is read from the data buffer and to be stored into a designated magnetic recording unit, the block number supplied from the data buffer and the block number assigned when the data was stored into the data buffer are compared, and then the data is stored into the magnetic recording unit.

Method and apparatus for controlling data writing in magnetic recording

When the mount and demount operation of information media are achieved between an information medium storage shelf and a plurality of recording/playback apparatuses by use of a plurality of handling devices, in order to execute the operations in a concurrent fashion without causing an interference between the handling devices for an increased operation efficiency, the area of the storage shelf and at least one of the recording/playback apparatuses are respectively subdivided into a plurality of subareas so as to process the obtained subareas by the plurality devices respectively associated therewith.

Automatic storage system and method for information recording media

An I/O control system includes an I/O control unit, a plurality of I/O devices, the start process prior to a data transfer process of the I/O device being off-line processed from the I/O control unit, and a data transfer path for data transferring to the I/O device, the data transfer being performed for one I/O device at a time. The I/O control unit controls an I/O device in such a way that the start process of the I/O device completes at the time when another I/O device under data transfer completes its data transfer, thus improving the utilization of a data transfer path.

I/O control system and method

Method for controlling information recording in an information recording apparatus which includes a rewritable information record medium containing a data record area having a plurality of data recording blocks and an alternative area in which data to be written into a defective block in the data record area is written, and writing and reading of data to and from the blocks and erasing of data may be carried out, wherein, data is written into the respective blocks in the data record area on the information record medium, and if a data record error is detected, data to be written into the defect block is written into a block of the alternative area. When data is subsequently rewritten, contents of all blocks in the data record area to be rewritten, including the block previously determined to be defective, are erased and the new data is rewritten, and the content of the alternative area is erased. If a data record error is detected after rewriting, the data to be written into the defect block is written into a block in the alternative area.

Information recording control system reusing a defective area

A method of controlling a write operation for a rotating type recording medium in which a plurality of tracks are formed in such a manner that each track is divided into a plurality of blocks having respective addresses and each block is used as the information recording/reproducing unit, is disclosed. In this method, each block includes an information recording field and a flag field for indicating the presence or absence of recorded information in the information recording field, to follow the following procedure. That is, when a high-ranking apparatus specifies a block and issues a write instruction for writing information in the specified block, the flag field of the specified block is first checked, and then the first recording mode for immediately recording new information in the information recording field of the specified block or the second recording mode for recording new information in the information recording field of the specified block after an erasing operation has been performed for the above information recording field, is executed depending upon whether the flag field of the specified block indicates the absence of recorded information or the presence of recorded information.

Method of controlling write operation for rotating type recording medium

An input/output control system has a control unit including a first controller connected between a channel and a data buffer for controlling the transfer of data therebetween and a second controller connected between the data buffer and a plurality of input/output devices for controlling the transfer of data therebetween. A start action of the input/output device is effected in an off-line mode from the control unit. The amount of data stored in the data buffer is checked each time the transfer of data occurs between the channel and the data buffer. In the case of a read processing, when the amount of data stored in the data buffer becomes less than a first predetermined value, data is transferred for preload from the input/output devices to the data buffer. In the case of a write processing, when the amount of data stored in the data buffer exceeds a second predetermined value, data is transferred for after-write from the data buffer to the input/output devices. Each of the first and second predetermined values is determined depending on the amount of input/output devices which are in an active state at that time. When each of the active input/output devices is allocated with m (.gtoreq.2) unit fields of the data buffer each of which has a capacity of K/(mn) where K is the whole capacity of the data buffer and n is the number of the active input/output devices, the first and second predetermined values may be K/(mn) respectively.

Data transfer control system for controlling data transfer between a

A data recording/reproducing method for a non-rewritable recording medium of a rotating type, each of tracks on the recording medium is divided into a plurality of blocks which are allotted with respective addresses. Each block includes a data recording area and a deletion flag area which is divided into a plurality of sub-areas. One of the sub-areas in a given block is associated with other block which is in a predetermined address relation with the given block. When the content in the data recording area of one block on the recording medium is to be rendered invalid, deletion flag information is also recorded in the sub-area of the other block having the predetermined address relation with the one block. Upon reading, the data of the blocks read out from the recording medium exclusive of the data of the block determined to be invalid on the basis of the flag information is transferred to a high-rank system.

Data recording and reproducing method

An information recording method and system for writing information onto a recording medium. If an error area is detected in a check of the information read out of the medium after writing, the information is rewritten onto an alternative area on the recording medium using a buffer memory while the information in the error area is kept valid. Loss time accessing the alternative area is eliminated until the error checking and correction in the error checking and correction circuit is not available for the information read out of the error area through a reading circuit.

Information recording system and method for using alternative record

In an information storage system including a rotating recording medium having a number of information tracks, a head positioning mechanism for switching access position between adjacent tracks and a plurality of buffer memories each capable of storing one track of data, an alternate record area for storing data in substitution for an error data block is provided at an end of each of the tracks of the recording medium, and if an error data block is detected by a read-after-write check of the data during the rotation of the disc after the data has been written in one of the tracks from one of the buffer memories during the previous rotation of the disc, the data from the other buffer memory is written in the adjacent track or the data is read from the adjacent track and checked during a disc rotation waiting time required before the data write operation to the alternate record area is started.

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Hadano, Japan

Takashi Doi