Abstract: To enable a physically rewritable disc to be appropriately used as a write-once type. When the rewritable disc is used in rewritable application, the position where writing of a predetermined data unit (for example, an ECC block) in data is started is set to a first position with respect to a reference position to record or play back the data. In contrast, when the rewritable disc is used in write-once application, the position where writing of the predetermined data unit in the data is started is set to a second position different from first position to record or play back the data.

Abstract: To enable a physically rewritable disc to be appropriately used as a write-once type. When the rewritable disc is used in rewritable application, the position where writing of a predetermined data unit (for example, an ECC block) in data is started is set to a first position with respect to a reference position to record or play back the data. In contrast, when the rewritable disc is used in write-once application, the position where writing of the predetermined data unit in the data is started is set to a second position different from first position to record or play back the data.

Abstract: A recording medium as a physically rewritable disk is appropriately used as a write-once type. In order to use the rewritable media in write-once applications, the recording medium in the data structure thereof includes, in a second data unit (an ECC block of 64 Kbytes), flag information WF1-WF4 indicating whether a first data unit (2 Kbytes) is stored. More specifically, whether a plurality of first data units (a sector handled by a host) has been recorded in the second data unit (a recording unit sector on the recording medium) is directly indicated. When an access request is issued in emulation in a disk drive device, the flag information is referenced, and the disk drive device determines whether one of writing or reading of the first data unit as a target responsive to a command is enabled.

Abstract: Pieces of address information are recorded on an optical disc such that they are successively continuous addresses within each zone but discontinuous at a beginning of a zone next to the previous zone, and an address after repeating the addresses of the previous zone for two rounds becomes the forefront address of the zone next to the previous zone. Access to the land tracks is performed by returning to the first address position in a zone after the addresses of the groove tracks become the last address of the zone, and the access is performed by recognizing an address continued from the last address of the groove tracks suppositionally on the pieces of address information recorded on the groove tracks, and then the access is successively performed to move to the next zone after the addresses of the land tracks become the last address of the zone.

Abstract: Pieces of address information are recorded on an optical disc such that they are successively continuous addresses within each zone but discontinuous at a beginning of a zone next to the previous zone, and an address after repeating the addresses of the previous zone for two rounds becomes the forefront address of the zone next to the previous zone. Access to the land tracks is performed by returning to the first address position in a zone after the addresses of the groove tracks become the last address of the zone, and the access is performed by recognizing an address continued from the last address of the groove tracks suppositionally on the pieces of address information recorded on the groove tracks, and then the access is successively performed to move to the next zone after the addresses of the land tracks become the last address of the zone.

Abstract: An optical disc apparatus and data recording method simplifies debugging when supplying a large quantity of software with a the reproducing only optical disc in place of a optical magnetic disc. The optical disc apparatus and data recording method converts a data sequence into a format to be recorded on reproducing only optical discs and records on an optical magnetic disc. The behavior when accessing optical discs will be restored in utilizing such optical magnetic disc.