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适用范围：This International Standard specifies the characteristics of 90 mm Optical Disk Cartridges (ODC) with a capacity of 230 Mbytes per Cartridge. The Standard specifies three related, but different implementations of such cartridges, viz. Type R/W Provides for data to be written, read and erased many times over the whole recording surface of the disk using the thermo-magnetic and magneto-optical effects. Type P-ROM Provides for a part of the disk surface to be embossed by stamping or other means. This part of the disk is read without recourse to the magneto-optical effect. All parts which are not embossed provide for data to meet the requirements of Type R/W. Type O-ROM Provides for the whole of the disk surface to be embossed and reproduced by stamping or other means. This type of disk is read without recourse to the magneto-optical effect. Type R/W, Type P-ROM and Type 0-ROM are also referred to as "fully rewritable", "partially embossed" and "fully embossed", respectively. This International Standard specifies - the conditions for conformance testing and the Reference Drive; - the environments in which the cartridges are to be operated and stored; - the mechanical and physical characteristics of the cartridge, so as to provide mechanical interchangeability between data processing systems; - the format of the information on the disk, both embossed and user-written; including the physical disposition of the tracks and sectors, the error correction codes, and the modulation method used; - the characteristics of the embossed information on the disk; - the magneto-optical characteristics of the disk, enabling processing systems to write data onto the disk; - the minimum quality of user-written data on the disk, enabling data processing systems to read data from the disk. This International Standard provides for interchange between optical disk drives. Together with a standard for volume and file structure, it provides for full data interchange between data processing systems.