This ECMA Standard specifies the file structure and the labeling of flexible disk cartridges for the interchange of information between users of different information processing systems.
This Standard specifies the file structure, the basic characteristics of the blocks containing the records constituting the file, the recorded labels to identify files, file sections, and volumes of flexible disk cartridges.
This Standard specifies three nested levels of interchange:
– at the first level, called BASIC INTERCHANGE (BI), it is possible to interchange data by using a minimum set of the facilities provided;
– at a second level, called EXTENDED INTERCHANGE LEVEL ONE(E1), it is possible to interchange data using the minimum set together with blocks having a length greater than that of the physical records and with blocked, fixed-length records;
– at a third level, called EXTENDED INTERCHANGE LEVEL TWO (E2), it is possible to interchange data using the facilities of levels BI and E1 together with variable-length records and segmented records.