BS ISO/IEC 11557:1992

Section 1 - General
1. Scope
2. Normative references
3. Conformance
3.1 Magnetic tape cartridge
3.2 Generating system
3.3 Receiving system
4. Definitions
4.1 Absolute Frame Number
4.2 Access Point
4.3 algorithm
4.4 Automatic Track Finding
4.5 Area ID
4.6 Average Signal Amplitude
4.7 azimuth
4.8 back surface
4.9 byte
4.10 cartridge
4.11 Channel Bit
4.12 Codeword
4.13 Data Format ID
4.14 Early Warning Point
4.15 End of Data
4.16 Entity
4.17 Error Correcting Code
4.18 flux transition position
4.19 flux transition spacing
4.20 frame
4.21 Housekeeping Frame
4.22 Logical Beginning of Tape
4.23 magnetic tape
4.24 Master Standard Amplitude Calibration Tape
4.25 Master Standard Reference Tape
4.26 Optimum Recording field
4.27 Partition boundary
4.28 Physical Beginning of Tape
4.29 Physical End of Tape
4.30 physical recording density
4.31 pre-recording condition
4.32 processing
4.33 processed data
4.34 Processed Record
4.35 Processed Record Sequence
4.36 Record
4.37 Reference Recording Field
4.38 reprocessing
4.39 Secondary Standard Amplitude Calibration Tape
4.40 Secondary Standard Reference Tape
4.41 Separator Mark
4.42 Standard Reference Amplitude
4.43 Tape Reference Edge
4.44 Test Recording Current
4.45 track
4.46 Unprocessed Data
4.47 Unprocessed Record
4.48 Virtual End of Tape
5. Environment and safety; Testing environment;
        Operating environment; Storage environment;
        Transportation; Safety; Flammability
Section 2 - Requirements for the case
6. Dimensional and mechanical characteristics of
        the case
6.1 General
6.2 Overall dimensions (figures 6 and 7()
6.3 Loading grip (figure 6)
6.4 Holding areas (figure 6)
6.5 Notches of the lid (figures 5 and 8)
6.6 Lid dimensions (figures 6 to 8)
6.7 Optical detection of the beginning and end of
        tape (figures 9 and 12)
6.8 Bottom side (figures 10 and 11)
6.8.1 Locking mechanism of the slider
6.8.2 Access holes
6.8.3 Recognition, sub-datums, and write-inhibit holes
6.8.4 Datum holes
6.8.5 Access room for tape guides
6.8.6 Holes for accessing the hubs
6.8.7 Internal structure of the lower half (figure 12)
6.8.8 Light path (figure 12)
6.8.9 Support Areas (figure 13)
6.8.10 Datum Areas (figure 13)
6.8.11 Relationship between Support and Datum Areas
        and Reference Plane Z (figure 14)
6.9 Hubs (figures 15 and 16)
6.10 Leader and trailer attachment
6.11 Interface between the hubs and the drive spindles
        (figure 17)
6.12 Opening of the lid (figure 18)
6.13 Release of the hub locking mechanism (figs.19,20)
6.14 Label areas (figs. 21, 22)
Section 3 - Requirements for the unrecorded tape
7. Mechanical, physical and dimensional
        characteristics of the tape
7.1 Materials
7.2 Tape length
7.2.1 Length of magnetic tape
7.2.2 Length of leader and trailer tapes
7.3 Tape width
7.4 Discontinuities
7.5 Total thickness
7.6 Longitudinal curvature
7.7 Cupping
7.8 Coating adhesion
7.9 Layer-to-layer adhesion
7.10 Tensile strength
7.10.1 Breaking strength
7.10.2 Yield strength
7.11 Residual elongation
7.12 Electrical resistance of coated surfaces
7.13 Light transmittance of the tape
8. Magnetic recording characteristics
8.1 Optimum Recording Field
8.2 Signal Amplitude
8.3 Resolution
8.4 Overwrite
8.4.1 Physical recording densities of 750,6 ftpmm and
        3 002 ftpmm
8.4.2 Physical recording densities of 83,4 ftpmm and
        1 001 ftpmm
8.5 Ease of erasure
8.6 Tape quality
8.6.1 Missing pulses
8.6.2 Missing pulse zone
8.7 Signal-to-Noise Ratio (S/N) characteristic
Section 4 - Requirements for an interchanged tape
9. Format
9.1 General
9.2 Basic Groups
9.2.1 Entity
9.2.2 Group Information Table
9.2.3 Block Access Table (BAT)
9.3 Sub-Groups
9.3.1 G1 Sub-Group
9.3.2 G2 Sub-Group - randomizing
9.3.3 G3 Sub-Group
9.3.4 G4 Sub-Group
9.3.5 Main Data Block
9.4 Sub-Data Area
9.4.1 to 9.4.8 Pack item Nos.1 to 8
9.4.9 Sub Data Block
10. Method of recording
10.1 Physical recording density
10.2 Long-term average bit cell length
10.3 Short-term average bit cell length
10.4 Rate of change
10.5 Bit shift
10.6 Read Signal Amplitude
10.7 Maximum recorded levels
11. Track geometry
11.1 Track configuration
11.2 Average track pitch
11.3 Variations of the track pitch
11.4 Track width
11.5 Track angle
11.6 Track edge linearity
11.7 Track length
11.8 Ideal tape centreline
11.9 Azimuth angles
12. Recording of blocks on the tape
12.1 Recorded Main Data Block
12.2 Recorded Sub Data Block
12.3 Margin Blocks, Preamble Blocks and Postamble
        Blocks
12.4 Spacer Blocks
13. Format of a track
13.1 Track capacity
13.2 Positioning accuracy
13.3 Tracking scheme
14. Layout of a Single Data Space tape
14.1 Device Area
14.2 Reference Area
14.3 Position tolerances band No.1
14.4 System Area
14.5 Data Area
14.5.1 Vendor Group
14.5.2 Recorded Data Group
14.5.3 ECC3
14.5.4 Multiple recorded instances
14.5.5 Repeated frames
14.5.6 Appending and overwriting
14.6 EOD Area
14.7 Post-EOD Area
14.8 Early Warning Point - EWP
14.9 Initialization
15. Layout of Partitioned tape
15.1 Overall magnetic tape layout
15.1.1 Device Area
15.1.2 Partition 1
15.1.3 Partition 0
15.2 Area ID
15.3 System Area Pack Items No. 3 and No. 4
15.4 Empty partitions
15.5 Initialization of Partitioned tapes
16. Housekeeping frames
16.1 Amble Frames
16.2 System Log Frames
16.3 Tape Management Frames
Numerous annexes

Specifies the magnetic and physical characteristics of a 3,81mm wide magnetic tape cartridge to enable interchangeability of such cartridges. Also specifies the quality of the recorded signal, the recorded format and the recording method. Coverage includes definitions, conformance and magnetic recording characteristics.

This International Standard specifies the physical and magnetic characteristics of a 3,81 mm wide magnetic tape cartridge to enable interchangeability of such cartridges. It also specifies the quality of the recorded signal, the recording method and the recorded format, thereby allowing data interchange between drives by means of such magnetic tape cartridges.

This International Standard specifies two types of cartridge which, for the purpose of this International Standard, are referred to as Type A and Type B.

For Type A, the magnetic tape is nominally 13 μm thick and has a length of up to 60,5 m.

For Type B, the magnetic tape is nominally 9 μm thick and has a length of up to 92,0 m.

The recorded format, known as Digital Data Storage - Data Compression (DDS-DC), includes all the features of the DDS recorded format specified in ISO/IEC 10777, with additional features which support the recording of data which has been processed, by the generating system, after receipt from the host and prior to recording. Such features are intended for, but are not limited to, the support of one or more data compression Algorithms.

Information interchange between systems by means of this International Standard also requires the use, at a minimum, of a labelling and file structure, an interchange code and a Processing Algorithm which are agreed upon by the interchange parties. It is not within the scope of this International Standard to specify the labelling and file structure, the interchange code or the Processing Algorithm.