BS 5769-1:1979

National foreword
Cooperating organizations
Specification
0 Introduction
1 Scope and field of application
2 References
3 Definitions
4 Basic system
4.1 Introduction
4.2 Use of tape marks
4.3 Structuring the files
4.4 Coincidence of end of file and intermediate start
     of track
4.5 Coincidence of end of file and intermediate end of
     track
4.6 End of available space
4.7 Recording density
4.8 By-pass or check-point records
5 Compact system
5.1 Introduction
5.2 Use of tape marks
5.3 Formats and contents of labels
5.4 Processing of label fields
5.5 Structuring the files
5.6 Recording density
5.7 By-pass or check-point records
6 Extended system
6.1 Introduction
6.2 Use of tape marks
6.3 Formats and contents of labels
6.4 Processing of label fields
6.5 Structuring the files
6.6 Use of optional labels
6.7 Recording density
6.8 By-pass or check-point records

Three systems of arrangement of magnetically recorded separators and labels. Support for the simplest \'basic\' system is necessary to ensure interchangeability of data.

This International Standard specifies file structures for data interchange on magnetic tape cassettes.

To provide for the range of sophistication in equipment and applications, three systems are specified:

1. the basic system, employing only hardware-defined separators to structure the files;
2. the compact system, employing special data blocks with information content (labels), which are capable of being recorded using only numeric equipment;
3. the extended system, employing the magnetic tape labelling system specified in ISO 1001 together with new labels, to define a more comprehensive labelling system.

This International Standard is not limited to the 3,81 mm magnetic tape cassette described in ISO 3407 but could also be applied to higher capacity cassettes or cartridges.