ISO/IEC 23651:2003

INTERNATIONAL ISO/IEC
STANDARD 23651
First edition
2003-08-01
Information technology — 8 mm wide
magnetic tape cartridge for information
interchange — Helical scan recording —
AIT-3 format
Technologies de l'information — Cartouche de bande magnétique de
8 mm de large pour échange d'informations — Enregistrement par
balayage en spirale — Format AIT-3

Reference number
©
ISO/IEC 2003
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©  ISO/IEC 2003
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or
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Published in Switzerland
ii © ISO/IEC 2003 – All rights reserved

Contents
Section 1 - Genera l 1
1Scope 1
2 Conformance 1
2.1 Magnetic tape cartridge 1
2.2 Generating drive 1
2.3 Receiving drive 1
3 Normative references 2
4 Terms and definitions 2
4.1 Absolute Frame Number (AFN) 2
4.2 a.c. erase 2
4.3 Access 2
4.4 algorithm 2
4.5 Area ID 2
4.6 Automatic Track Finding (ATF) 2
4.7 Average Signal Amplitude 2
4.8 azimuth 2
4.9 back surface 2
4.10 byte 2
4.11 cartridge 2
4.12 Channel bit 3
4.13 Codeword 3
4.14 Early Warning Point (EWP) 3
4.15 End of Data (EOD) 3
4.16 Entity 3
4.17 Error Correcting Code (ECC) 3
4.18 flux transition position 3
4.19 flux transition spacing 3
4.20 Frame 3
4.21 Housekeeping Frame 3
4.22 Logical Beginning of Tape (LBOT) 3
4.23 magnetic tape 3
4.24 Master Standard Amplitude Calibration Tape 3
4.25 Master Standard Reference Tape 3
4.26 Partition Boundary 3
4.27 Physical Beginning of Tape (PBOT) 3
4.28 Physical End of Tape (PEOT) 4
4.29 physical recording density 4
4.30 pre-recording condition 4
4.31 processing 4
4.32 processed data 4
4.33 Processed Record 4
4.34 record 4
4.35 Reference Field 4
4.36 Remote Memory In Cartridge (RMIC) 4
4.37 Secondary Standard Amplitude Calibration Tape 4
4.38 Secondary Standard Reference Tape 4
© ISO/IEC 2003 – All rights reserved iii

4.39 Separator Mark 4
4.40 Standard Reference Amplitude (SRA) 4
4.41 Standard Reference Current 4
4.42 Tape Reference Edge 4
4.43 Test Recording Current 4
4.44 track 5
4.45 Typical Field 5
4.46 unprocessed data 5
4.47 Unprocessed Record 5
5 Conventions and Notations 5
5.1 Representation of numbers 5
5.2 Names 5
6 Acronyms 5
7 Environment and safety 6
7.1 Test environment 6
7.2 Operating environment 6
7.3 Storage environment 6
7.4 Transportation 6
7.5 Safety 6
7.6 Flammability 6
Section 2 - Requirements for the case 6
8 Dimensional and mechanical characteristics of the case 6
8.1 General 6
8.2 Overall dimension 7
8.3 Holding areas 7
8.4 Cartridge insertion 8
8.5 Window 8
8.6 Loading grips 9
8.7 Label areas 9
8.8 Datum areas and Datum holes 9
8.9 Support areas 10
8.10 Recognition holes 10
8.11 Write-inhibit hole 11
8.12 Pre-positioning surfaces 12
8.13 Cartridge lid 12
8.14 Cartridge reel lock 13
8.15 Reel access holes 14
8.16 Interface between the reels and the drive spindles 14
8.17 Light path 15
8.18 Position of the tape in the case 16
8.19 Tape path zone 16
8.20 Tape access cavity 16
8.21 Tape access cavity clearance 17
8.22 Requirements for the RMIC 17
8.23 Recognition recesses 18
Section 3 - Requirements for the unrecorded tape 38
9 Mechanical, physical and dimensional characteristics of the tape 38
9.1 Materials 38
9.2 Tape length 38
iv © ISO/IEC 2003 – All rights reserved

9.2.1 Length of magnetic tape 38
9.2.2 Length of leader and trailer tapes 38
9.2.3 Length of the splicing tapes 38
9.3 Tape width 38
9.3.1 Width of magnetic, leader and trailer tapes 38
9.3.2 Width and position of the splicing tape 38
9.4 Discontinuities 39
9.5 Tape thickness 39
9.5.1 Thickness of the magnetic tape 39
9.5.2 Thickness of the leader and trailer tape 39
9.5.3 Thickness of the splicing tape 39
9.6 Longitudinal curvature 39
9.7 Cupping 39
9.8 Coating adhesion 39
9.9 Layer-to-layer adhesion 40
9.10 Tensile strength 40
9.10.1 Breaking strength 40
9.10.2 Yield strength 40
9.11 Residual elongation 40
9.12 Electrical resistance of the recording surface 40
9.13 Tape winding 41
9.14 Light transmittance of the tape 41
9.15 Recognition stripe 41
10 Magnetic recording characteristics 42
10.1 Typical Field 42
10.2 Signal Amplitude 42
10.3 Resolution 43
10.4 Overwrite 43
10.5 Ease of erasure 43
10.6 Tape quality 43
10.6.1 Missing pulses 43
10.6.2 Missing pulse zone 43
10.7 Signal-to-Noise Ratio (SNR) characteristic 43
Section 4 - Requirements for an interchanged tape 44
11 Format 44
11.1 General 44
11.2 Basic Groups 44
11.2.1 Entity 45
11.2.2 Group Information Table 45
11.2.3 Block Access Table (BAT) 48
11.3 Sub-Groups 50
11.3.1 G1 Sub-Group 50
11.3.2 G2 Sub-Group - Randomizing 51
11.3.3 G3 Sub-Group 52
11.4 Data Block 53
11.4.1 ID information 53
11.4.2 Recording of the ID Information in the Data Block Headers 56
12 Method of recording 61
12.1 Physical recording density 62
12.2 Long-term average bit cell length 62
12.3 Short-term average bit cell length 62
12.4 Rate of change 62
© ISO/IEC 2003 – All rights reserved v

12.5 Bit shift 62
12.6 Read signal amplitude 62
12.7 Maximum recorded levels 62
13 Track geometry 62
13.1 Track configuration 62
13.2 Average track pitch 63
13.3 Variations of the track pitch 63
13.4 Track width 63
13.5 Track angle 63
13.6 Track edge straightness 63
13.7 Track length 63
13.8 Azimuth angles 63
14 Recorded patterns 64
14.1 Recorded Data Block 64
15 Format of tracks 64
15.1 Track structure 64
15.2 Positioning accuracy 64
15.3 Tracking scheme 64
15.4 Generation of Margin Blocks 65
16 Layout of the tape 66
16.1 Device Area 66
16.2 Reference Area 67
16.3 Position Tolerance Band No. 1 67
16.4 System Area 67
16.4.1 System Preamble 67
16.4.2 System Log 67
16.4.3 System Postamble 72
16.4.4 Position Tolerance Band No. 2 72
16.4.5 Vendor Group Preamble 72
16.5 Data Area 72
16.5.1 Vendor Group 72
16.5.2 Recorded Data Group 72
16.5.3 ECC3 73
16.5.4 Multiple Recorded Instances 74
16.5.5 Repeated Frames 74
16.5.6 Appending and overwriting 75
16.6 EOD Area 76
16.7 Optional Device Area 76
16.8 Logical End Of Tape (LEOT) 77
16.9 Logical Beginning of Tape (LBOT) 77
16.10 Early Warning Point - EWP 77
16.11 Empty Partition 77
16.12 Initialization 77
17 Housekeeping Frames 78
17.1 Amble Frames 78
17.2 System Amble Frames 78
18 AIT Remote Memory In Cartridge (AIT RMIC) 78
18.1 General 78
18.2 Content of the AIT RMIC 78
18.2.1 Manufacturer's Information Section 79
vi © ISO/IEC 2003 – All rights reserved

18.2.2 Communication Information Section 82
18.2.3 Mechanism Error Log Information Section 82
18.2.4 Memory Management Information Section 83
18.2.5 Volume Information Section 84
18.2.6 Volume Use History Information Section 85
18.3 Memory Heap Management 85
18.3.1 Cell 85
18.3.2 Cell Header 85
18.3.3 Partition Information Cell 87
18.3.4 Physical Tape Directory Information Cell 87
18.3.5 User Volume Information Cell 88
18.3.6 User Partition Information Cell 88
18.3.7 Application Information Cell 89
18.3.8 Date and Time Stamp Information Cell 90
18.3.9 Media Identification Information Cell 91
18.3.10 Tape Alert Information Cell 91
18.4 Electrical interface 92
18.5 Environment 92
18.5.1 Electromagnetic Compatibility 92
18.5.2 Magnetic fields 92
18.5.3 X-rays 92
18.6 Operating Field 92
18.7 Message from AIT RMIC reader-writer to AIT RMIC 92
18.8 Message from AIT RMIC to AIT RMIC reader-writer 93
18.8.1 Load modulation 94
18.9 EDC 95
18.10 AIT RMIC states 95
18.11 Command and Response 96
18.11.1 Attention Command and Response 97
18.11.2 Attention Command and Response Type 1 97
18.11.3 Attention Command and Response Type 2 97
18.11.4 Read Command and Response 98
18.11.5 Write Command and Response 98
18.11.6 Status Command and Response 98
18.11.7 Reset Command and Response 99
18.12 Dialogue 99
18.12.1 Read data from AIT RMIC 99
18.12.2 WritedatatoAIT RMIC 100
18.12.3 Read and Write with Session ID 101
Annexes
A (normative) - Measurement of light transmittance 105
B (normative) - Measurement of Signal-to-Noise Ratio 108
C (normative) - Method for determining the nominal and the maximum allowable recorded levels
(pre-recording condition) 109
D (normative) - Representation of 16-bit words by 18-Channel bits patterns 110
E (normative) - Measurement of bit shift 111
F (normative) - Method of measuring the straightness of track edges 113
G (normative) - ECC calculation 114
H (informative) - Recommendations for transportation 117
J (informative) - Read-After-Write 118
© ISO/IEC 2003 – All rights reserved vii

K (informative) - Basic Group No. 0 119
L (informative) - Chip for the AIT-3 format 120
M (informative) - Generation of EDC bytes for the Error Detecting Code for G2 Sub-Groups 121
viii © ISO/IEC 2003 – All rights reserved

Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical Commission) form the
specialized system for worldwide standardization. National bodies that are members of ISO 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. ISO and IEC technical committees collaborate in fields of mutual interest. Other
international organizations, governmental and non-governmental, in liaison with ISO and IEC, also take part in the work. In
the field of information technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of the joint technical committee is to prepare International Standards. 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.
ISO/IEC 23651 was prepared by ECMA (as ECMA-329) 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 ISO and IEC.
© ISO/IEC 2003 – All rights reserved ix

INTERNATIONAL STANDARD ISO/IEC 23651:2003(E)

Information technology — 8 mm wide magnetic tape cartridge for information
interchange — Helical scan recording — AIT-3 format
Section 1 - General
1Scope
This International Standard specifies the physical and magnetic characteristics of an 8 mm wide magnetic tape cartridge
containing a memory chip to enable physical interchange of such cartridges between drives. It also specifies the quality of the
recorded signals, the recording method and the recorded format - called Advanced Intelligent Tape No. 3 (AIT-3 format) -
thereby allowing data interchange between drives by means of such magnetic tape cartridges.
This International Standard specifies two types of cartridge depending on the thickness of the magnetic tape contained in the
case.
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.
2 Conformance
2.1 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.
2.2 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 one or both methods of
appending and overwriting are implemented. In addition, such a drive shall be able to record the System Log in the AIT
Remote Memory In Cartridge (AIT RMIC).
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 compress data
received from the host prior to collecting the data into Basic Groups, and
− the registered identification number(s) of the implemented compression algorithm(s).
2.3 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 read the System Log recorded in the AIT RMIC;
− be able to recognise repeated frames, and to make available to the host, data and Separator Marks from only one of these
frames;
− be able to recognise multiple representations of the same Basic Group, and to make available to the host, data and
Separator Marks from only one of these representations;
− be able to recognise an ECC3 frame, and ignore it if the system is not capable of using ECC
...