Method and apparatus for recording and reproducing information in black

Abstract

An information recording and reproducing device uses a recording medium which is provided with units composed of blocks and a unit information recording area which includes unit allocation information, sector number information indicating the number of sectors per unit and unit number information identifying each unit. When the recording medium is placed in the device, the respective information is read by a calculating unit which calculates physical sector numbers corresponding to a block specified for recording and reproduction operations. Access operations are performed to the calculated sectors, which allows the desired information to be recorded. The block includes dummy sectors which are added before and after each group of predetermined numbers of effective sectors. When high-volume information is recorded over several blocks, the dummy sectors may be provided only for the first and last blocks. The device records a group of information whose volume varies from the smallest block number toward the larger block numbers, while it records a group of information whose volume is fixed from the largest block number. Thus, the recording area is effectively used. The device easily conducts the information management when a host device specifies a block. The file management may be executed by providing a unit for recording file management information separately from a unit for recording files.