BS ISO/IEC 12247:1993

Section 1 - General
1 Scope
2 Conformance
2.1 Magnetic tape cartridge
2.2 Generating system
2.3 Receiving system
3 Normative references
4 Definitions
4.1 Absolute Frame Number (AFN)
4.2 Area ID
4.3 Automatic Track Finding (ATF)
4.4 Average Signal Amplitude
4.5 azimuth
4.6 back surface
4.7 byte
4.8 cartridge
4.9 Channel Bit
4.10 Data Format ID
4.11 Early Warning Point (EWP)
4.12 End of Data (EOD)
4.13 Error Correcting Code (ECC)
4.14 flux transition position
4.15 flux transition spacing
4.16 frame
4.17 Housekeeping Frame
4.18 Logical Beginning of Tape (LBOT)
4.19 magnetic tape
4.20 Master Standard Amplitude Calibration Tape
4.21 Master Standard Reference Tape
4.22 Optimum Recording Field
4.23 partition boundary
4.24 Physical Beginning of Tape (PBOT)
4.25 Physical End of Tape (PEOT)
4.26 physical recording density
4.27 pre-recording condition
4.28 record
4.29 Reference Recording Field
4.30 Secondary Standard Amplitude Calibration Tape
4.31 Secondary Standard Reference Tape
4.32 Separator Mark
4.33 Standard Reference Amplitude
4.34 Tape Reference Edge
4.35 Test Recording Current
4.36 track
4.37 Virtual End of Tape (VEOT)
5 Environment and safety
5.1 Testing environment
5.2 Operating environment
5.3 Storage environment
5.4 Transportation
5.5 Safety
5.6 Flammability
Section 2 - Requirements for the case
6 Dimensional and mechanical characteristics of
        the case
6.1 General
6.2 Overall dimensions
6.3 Loading grip
6.4 Holding areas
6.5 Notches of the lid
6.6 Lid dimensions
6.7 Optical detection of the beginning and end of tape
6.8 Bottom side
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
6.8.8 Light path
6.8.9 Support Areas
6.8.10 Datum Areas
6.8.11 Relationship between Support and Datum Areas and
        Reference Plane Z
6.9 Hubs
6.10 Leader and trailer attachment
6.11 Interface between the hubs and the drive spindles
6.12 Opening of the lid
6.13 Release of the hub locking mechanism
6.14 Label areas
Section 3 - Requirements for the unrecorded tape
7 Mechanical, physical and dimensional
        characteristics of the tape
7.1 Materials
7.2 Tape length
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
7.11 Residual elongation
7.12 Electrical resistance of coated surfaces
7.13 Light transmittance of the tape
8 Magnetic recording characteristics
8.1 Optimum Recoding 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 Group Information Table
9.2.2 Block Access Table
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 Pack Item No. 1
9.4.2 Pack Item No. 2
9.4.3 Pack Item No. 3
9.4.4 Pack Item No. 4
9.4.5 Pack Item No. 5
9.4.6 Pack Item No. 6
9.4.7 Pack Item No. 7
9.4.8 Pack Item No. 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 ength
11.8 Ideal tape centreline
11.9 Azimuth angle
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 Tolerance Band No. 1
14.4 System Area
14.5 Data Area
14.6 EOD Area
14.7 Post-EOD Area
14.8 Early Warning Point - EWP
14.9 Initialization
15 Layout of a partitioned tape
15.1 Overall magnetic tape layout
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
Annexes
A Measurement of the light transmittance of the
        prisms
B Recognition Holes
C Means to open the lid
D Measurement of light transmittance of tape and
        leaders
E Measurement of Signal-to-Noise Ratio
F Method for determining the nominal and the
        maximum allowable recorded levels
G Representation of 8-bit bytes by 10-bit patterns
H Measurement of bit shift
J Recommendations for transportation
K Method of measuring track edge linearity
L Read-After-Write
M Example of the content of a Basic Group No. 0
N Media Recognition System (MRS)

Specifies the physical and magnetic characteristics of a 3,81 mm wide magnetic tape cartridge to enable interchangeability of such cartridges. Coverage includes: environment and safety; dimensional and mechanical characteristics of the case; magnetic recording characteristics; method of recording; track geometry; recordings of blocks on the tape; layout of a single data space tape; layout of a partitioned tape. Also gives definitions and detailed annexes.

This International Standard specifies the physical and magnetic characteristics of a 3,81mm wide magnetic tape cartridge to enable interchangeability of such cartridges. It also specifies the quality of the recorded signals, the recorded format and the recording method, thereby allowing data interchange between drives by means of such magnetic tape cartridges. The format used is known as Digital Data Storage (DDS).

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

For TypeA, the magnetic tape has a nominal thickness of 13pm and a nominal length of up to 60,5m.

For TypeB, the magnetic tape has a nominal thickness of 9pm and a nominal length of up to 92,0m.

Information interchange between systems by means of this International Standard also requires the use, at a minimum, of a labelling and file structure and an interchange code 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, or the interchange code.