Abstract:
A tape drive apparatus has at least one rotary head for reading/writing a track. The track has a number of fragments and each fragment has an identifier. The tape drive apparatus has a position indicator apparatus for providing a signal that indicates a rotational position of the head. The combination of the signal and the identifier unequivocally identifies a fragment within the fragments of a track. This has the advantage that non-unique identifiers can be used for the fragments of a track.
Abstract:
A data reader reads a medium holding user and non-user data that holds information relating to the user data. The reader has a read head that generates a data signal comprising user and non-user data. The user data is arranged into plural sets interspersed with the non-user data that identifies the user data within the sets. Processing circuitry receives and processes the data signal and obtains the user data from the data signal by using the non-user data to identify the user data within the data signal. The data reader is particularly suitable in situations having re-writes and overwrites.
Abstract:
There is described a tape format and a method for formatting a length of magnetic tape with a number of system zones. Each system zone contains an area for mechanical load/unload operations or threading operations and an area containing volume format information for the entire magnetic media.
Abstract:
A tape cassette and tape recording/reproducing apparatus including a tape partitioned into a plurality of partitions for recording data thereon, and a separate memory included in the tape cassette for storing control information relating to each tape partition, thereby reducing the time and number of operations needed to access a particular partition.
Abstract:
A method of appending data to compressed data stored on tape (10) in the form of records (CR.sub.n) wherein compressed data is stored in groups (G.sub.n) independently of the record structure of the data and each group has an associated data structure (4), containing information relating to the group contents in terms of entities (E.sub.n), where an entity can contain more than one record, and means (H) for storing information on the number of records in each entity (E.sub.n) characterised by locating the entity containing the last record to be retained and changing said stored information to indicate the number of wanted records in that entity and writing the data being appended to a subsequent new entity.
Abstract:
A recording and reproducing system which has the capability of recording user data and system format data in physical blocks of predetermined size on a recording area of a tape, with the user data being identified by files and contained in data blocks having a predetermined size. Partial overrecording of data blocks can be performed in that physical blocks are retained which have valid data blocks, and new physical blocks are then recorded beginning with a rewritten data block.
Abstract:
Separations between the end of one data file and the beginning of the next data file are recognized, without utilizing an entire data storage block by means of a controlling program for a peripheral recording device monitoring the control information headers of helically stored data on a recording tape. When files are stored on the recording tape, the controlling program increments an increase of a file section number by one and increments to zero a data block number at the beginning of a new data file. When the recording device is reading the recording tape and there is detected an incrementation of the file section number and a zero value for a data block number, a recognition is made that this data indicates the end of one data file and the beginning of another data file.
Abstract:
An information data recording/reproducing apparatus where input information data is divided into sectors and distributed to be recorded on a magnetic tape by a plurality of magnetic heads. In a recording mode, the sector phase of the information data to be recorded is identified by input sync data which represents the phase relation thereto. In a playback mode, the sync data which identifies the sector phase of the recorded information data is obtained form the magnetic tape and used to control the playback operation. The phase relation of the information data can be restored exactly.
Abstract:
A method for formatting a length of magnetic tape into a plurality of partition areas to enable data storage in any of these areas and for formatting on the magnetic tape a plurality of spaced system zones, by means of controlling programs of a recording device prompting a host computer system to input the number and spacing of the system zones and the length and number of the partitions to be formatted onto the magnetic tape. The programs also prompts the host computer system to select one of various options for placing a partitions on the magnetic tape.
Abstract:
A data recording/reproducing device updates the identification data for identifying the recording data of recording track on the magnetic tape as the meaningless data. As a result, in a data recording reproducing device to be used for, such as an external memory device of the computer, the desired data can be erased easily.