ISO/IEC 15521:1998

INTERNATIONAL
ISOAEC
STANDARD
First edition
1998-06-01
Information technology - 3,81 mm wide
magnetic tape cartridge for information
interchange - Helical scan recording -
DDS-3 format using 125 m length tapes
Technologies de I’informa tion - Cartouche de bande magn&ique de
3,81 mm de large pour khange d ’information - Enregistrement par
balayage en spirale - Format DDS-3 utilisant des bandes de 125 m de
long
Reference number
ISOAEC 15521 :I 998(E)
ISWIEC 15521:1998(E)
Contents
1 Scope
2 Conformance
2.1 Magnetic tape cartridge
2.2 Generating drive
2.3 Receiving drive
3 Normative References
4 Definitions
4.1 Absolute Frame Number (AFN)
4.2 a.c. erase
4.3 Access Point
4.4 algorithm
4.5 Area ID
4.6 Average Signal Amplitude
4.7 azimuth
4.8 back surface
4.9 byte
4.10 cartridge
4.1 1 Channel bit
4.12 Codeword
4.13 Data Format ID
4.14 Early Warning Point (EWP)
4.15 End of Data (EOD)
4.16 Entity
4.17 Error Correcting Code (ECC)
4.18 flux transition position
4.19 flux transition spacing
4.20 Fragment
4.2 1 Frame
4.22 Housekeeping Frame
4.23 Logical Beginning of Tape (LBOT)
4.24 magnetic tape
4.25 Master Standard Amplitude Calibration Tape
4.26 Master Standard Reference Tape
4.27 Optimum Recording Field
4.28 Partition Boundary
4.29 Physical Beginning of Tape (PBOT)
4.30 Physical End of Tape (PEOT)
4.3 1 physical recording density
4.32 pre-recording condition
4.33 processing
4.34 processed data
4.35 Processed Record
4.36 Processed Record Sequence
0 ISO/IEC 1998
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ii
OISO/IEC
4.37 record
4.38 Reference Recording Field
4.39 reprocessing
4.40 Secondary Standard Amplitude Calibration Tape
Secondary Standard Reference Tape
4.4 1
4.42 Separator Mark
4.43 Standard Reference Amplitude
4.44 Tape Reference Edge
4.45 Test Recording Current
4.46 track
unprocessed data
4.47
4.48 Unprocessed Record
4.49 Virtual End of Tape (VEOT)
5 Conventions and Notations
6 Acronyms
7 Environment and safety
7.1 Testing environment
7.2 Operating environment
7.3 Storage environment
Transportation
7.4
7.5 Safety
7.6 Flammability
8 Dimensional and mechanical characteristics of the case
8.1 General
8.2 Overall dimensions
8.3 Loading grip
8.4 Holding areas
8.5 Notches of the lid
8.6 Lid dimensions
8.7 Optical detection of the beginning and end of tape
8.8 Bottom side
8.8.1 Locking mechanism of the slider
8.8.2 Access holes
8.8.3 Recognition, sub-datums, and write-inhibit holes
8.8.4 Datum holes
8.8.5 Access room for tape guides
8.8.6 Holes for accessing the hubs
8.8.7 Internal structure of the lower half
8.8.8 Light path
8.8.9 Support Areas
8.8.10 Datum Areas
8.8.11 Relationship between Support and Datum Areas and Reference Plane 2
8.9 Hubs
8.10 Attachment of leader and trailer tapes
8.11 Interface between the hubs and the drive spindles
8.12 Opening of the lid
8.13 Release of the hub locking mechanism
8.14 Label areas
8.15 Requirement for autoloaders
9 Mechanical, physical and dimensional characteristics of the tape
. . .
USOIIEC
ISWIEC 15521:1998(E)
9.1 Materials
9.2 Tape length
9.2-l Length of magnetic tape
9.2.2 Length of leader and trailer tapes
9.2.3 Length of splicing tapes
9.3 Tape width
9.3.1 Width of magnetic tape
9.3.2 Width of leader and trailer tapes
9.3.3 Width and position of splicing tape
9.3.4 Edge weave
9.4 Discontinuities
9.5 Tape thickness
95.1 Thickness of magnetic tape
9.5.2 Thickness of leader and trailer tape
9.53 Thickness of splicing tape
9.6 Longitudinal curvature
9.7 Cupping
9.8 Coating adhesion
9.9 Layer-to-layer adhesion
9.10 Tensile strength
9.10-l Breaking strength
9.10.2 Yield strength
9.1 1 Residual elongation
9.12 Flexural rigidity
9.13 Electrical resistance of coated surfaces
9.14 Light transmittance of the tape
9.15 Media Recognition System (MRS)
10 Magnetic recording characteristics
10.1 Optimum Recording Field
10.2 Signal Amplitude
Resolution
10.3
10.4 Overwrite
10.5 Ease of erasure
10.6 Tape quality
10.6-l Missing pulses
10.6.2 Missing pulse zone
10.7 Signal-to-Noise Ratio (SNR) characteristic
11 Format
1 1.1 General
11.2 Basic Groups
11.2.1 Entity
1 1.2.2 Group Information Table
11.2.3 Block Access Table (BAT)
11.3 Sub-Groups
11.3.1 Gl Sub-Group
11.3.2 G2 Sub-Group - randomizing
11.3.3 G3 Sub-Group
11.3.4 G4 Sub-Group
11.3.5 Main Data Fragment
11.36 Summary of the transformation of a Basic Group
11.4 Sub code Information
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OISOIIEC
1 1.4.1 Pack Item Number 0
11.4.2 Pack Item Number 1
11.4.3 Pack Item Number 2
11.4.4 Pack Item Number 3
11.4.5 Pack Item Number 4
11.4.6 Pack Item Number 5
11.4.7 Pack Item Number 6
11.4.8 Pack Item Number 7
11.4.9 Pack Item Number 8
1 1.4.10 Pack Item Number 9
11.4.1 1 Pack Item Number 10
1 1.4. I2 Pack Item Number 11
1 1.4.13 Pack Item Number 12
1 1.4.14 Pack Item Number 13
11.4.15 Pack Item Number 14
1 1.4.16 Pack Item Number 15
11.5 Sub code location
11.5.1 Sub code Pack Items on a Single Data Space tape
11.5.2 Sub code Pack Items on a partitioned tape
12 Method of recording
12.1 Physical recording density
12.2 Long-term average bit cell length
12.3 Short-term average bit cell length
12.4 Rate of change
12.5 Bit shift
12.6 Read signal amplitude
12.7 Maximum recorded levels
13 Track geometry
13.1 Track configuration
13.2 Average track pitch
13.3 Variations of the track pitch
13.4 Track width
13.5 Track angle
13.6 Track edge linearity
13.7 Track length
13.8 Ideal tape centreline
13.9 Azimuth angles
14 Recorded patterns
14.1 Recorded Main Data Fragment
14.2 Preamble Zone, Margin Zones
15 Format of a track
15.1 Format of a track
15.2 Positioning accuracy
15.3 Tracking scheme
16 Layout of a Single Data Space tape
16.1 Device Area
16.2 Reference Area
16.3 Position Tolerance Band No. 1
16.4 System Area
16.4.1 System Preamble
OISO/IEC
16.4.2 System Log
16.4.3 System Postamble
16.4.4 Position Tolerance Band NO. 2
16.4.5 Vendor Group Preamble
16.5 Data Area
16.5.1 Vendor Group
16.5.2 Recorded Data Group
16.5.3 ECC3
16.5.4 Repeated Frames
g and overwriting
16.5.5 Appendin
16.6 EOD Area
16.7 Post-EOD Area
16.8 Early Warning Point - (EWP)
16.9 Initialization
17 Layout of a partitioned tape
17.1 Overall magnetic tape layout
17.1.1 Device Area
17.1.2 Partition 1
17.1.3 Partition 0
17.2 Area ID
17.3 System Area Pack Items No. 3 and No. 4
17.4 Empty partitions
17.4.1 Empty partition 1
17.4.2 Empty partition 0
17.5 Initialization of partitioned tapes
18 Housekeeping Frames
18.1 Amble Frames
18.2 System Log Frames
18.3 Tape Management Frames
Annexes
A - Measurement of the light transmittance of the prisms
B - Measurement of light transmittance of tape and leaders
C - Measurement of Signal-to-Noise Ratio
D - Method for determining the nominal and the maximum allowable recorded levels
E - Representation of g-bit bytes by IO-bit patterns
F - Measurement of bit shift
G - Measurement of track edge linearity
H - Recognition Holes
J - Means to open the lid
K - Recommendations for transportation
L - Read-After-Write.
M - Example of the content of a Basic Group No. 0.
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OISO/IEC
Foreword
IS0 (the International Organization for Standardization) and IEC (the International Electrotechnical Commission) form the
specialized system for worldwide standardization. National Bodies that are members of IS0 or IEC participate in the
development of International Standards through technical committees established by the respective organization to deal with
particular fields of technical activity. IS0 and IEC technical committees collaborate in fields of mutual interest. Other
international organizations, governmental and non-governmental, in liaison with IS0 and IEC, also take part in the work.
In the field of information technology, IS0 and IEC have established a joint technical committee, ISO/IEC JTC 1. Draft
International Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the national bodies casting a vote.
International Standard ISO/IEC 15521 was prepared by JISC (as Standard JIS X.61 30- 1996) with document support and
contribution from ECMA and was adopted, under a special “fast-track procedure” by joint Technical Committee ISO/IEC
JTC 1, Information technology, in parallel with its approval by national bodies of IS0 and IEC.
Annexes A, B, C, D, E, F and G form an integral part of this International Standard. Annexes H, J, K, L and M are for
information only.
vii
INTERNATIONAL STANDARD OISO/IEC ISOIIEC 15521:1998(E)
Information technology - 341 mm wide magnetic tape cartridge for information interchange -
Helical scan recording - DDS-3 format using 125 m length tapes
Scope
This International Standard specifies the physical and magnetic characteristics of a 3,81 mm wide magnetic tape cartridge to
enable physical interchangeability of such cartridges between drives. It also specifies the quality of the recorded signals, the
recording method and the recorded format - called Digital Data Storage (DDS) - thereby allowing data interchange between
drives by means of such magnetic tape cartridges.
Information interchange between systems also requires, at a minimum, agreement between the interchange parties upon the
interchange code(s) and the specifications of the structure and labelling of the information on the interchanged cartridge.
Under information interchange circumstances in which a processing algorithm, e .g. for lossless data compression as specified in
ISO/IEC 11558, is applied to the host data prior to recording on the tape and a complementary reprocessing algorithm is
applied after the data is read from the tape, agreement upon these by the interchange parties is also required.
2 Conformance
21 . Magnetic tape cartridge
A tape cartridge shall be in conformance with this International Standard if it meets all the mandatory requirements specified
herein. The tape requirements shall be satisfied throughout the extent of the tape.
For each recorded Entity any algorithm for lossless data compression used for processing the data therein shall have been
registered, and according to ISO/IEC 1 1576 the corresponding numerical identifier shall be recorded in Byte No. 3 of the
Entity Header.
22 . Generating drive
A drive generating a magnetic tape cartridge for interchange shall be in conformance with this International Standard if all
recordings on the tape meet the mandatory requirements of this International Standard, and if either or both methods of
appending and overwriting are implemented.
A claim of conformance shall state which of the following optional features are implemented and which are not
- the performing of a Read-After-Write check and the recording of any necessary repeated frames;
- the generation of ECC3 Frames.
In addition a claim of conformance shall state
-
whether or not one, or more, registered algorithm(s) are implemented within the system and are able to process data
received from the host prior to collecting the data into Basic Groups, and
- the algorithm registration identification number(s) of the implemented algorithm(s).
23 . Receiving drive
A drive receiving a magnetic tape cartridge for interchange shall be in conformance with this International Standard if it is able
to handle any recording made on the tape according to this International Standard. In particular it shall
- be able to recognize repeated frames and to make available to the host, data and Separator Marks from only one of these
frames;
- be able to recognize an ECC3 frame, and ignore it if the system is not capable of using ECC3 check bytes in a process of
error correction;
- be able to recognize processed data within an Entity, identify the algorithm used, and make the algorithm registration
number available to the host;
- be able to make processed data available to the host.
In addition a claim of conformance shall state
-
whether or not the system is capable of using ECC3 check bytes in a process of error correction;
XSO/IEC 15521:1998(E) OISO/IEC
-
whether or not one or more reprocessin, 0 algorithm(s) are implemented within the system, and are able to be applied to
processed data prior to making such data available to the host;
-
the algorithm registration number(s) of the processing algorithm(s) for which a complementary reprocessing algorithm is
implemented.
3 Normative References
The following standards contain provisions which, throu,oh reference in this text, constitute provisions of this International
Standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to
.
agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent
editions of standards indicated below. Members of TEC and IS0 maintain registers of currently valid International Standards.
IS0 527 (all parts), Plastics - Detemi~latiwz of tensile properties.
Technical drawings - Method of indica tirig surjYace textwe.
IS0 1302: 1992,
ISOAEC 11557: 1992, L~fornza tion technolo
...