1、Standard ECMA-292December 1999Standardizing Information and Communication SystemsPhone: +41 22 849.60.00 - Fax: +41 22 849.60.01 - URL: http:/www.ecma.ch - Internet: helpdeskecma.ch8 mm Wide Magnetic TapeCartridge for InformationInterchange - Helical ScanRecording AIT-2 with MICFormatStandard ECMA-2
2、92December 1999Standardizing Information and Communication SystemsPhone: +41 22 849.60.00 - Fax: +41 22 849.60.01 - URL: http:/www.ecma.ch - Internet: helpdeskecma.chMB ECMA-292.DOC 05-09-00 15,518 mm Wide Magnetic TapeCartridge for InformationInterchange - Helical ScanRecording - AIT-2 With MICForm
3、at.Brief HistoryTechnical Committee ECMA TC17 has produced a series of ECMA Standards for magnetic tape cassettes andcartridges of different widths, e.g. 12,7 mm, 8 mm, 6,35 mm and 3,81 mm. In each series, the standards correspond tospecific types of application and user requirements. Enhanced and n
4、ew media also correspond to advancements indrive technology. The series of helically recorded cartridges with a magnetic tape of 8 mm width comprises thefollowing standards.ECMA-145 (1990) 8 mm Wide Magnetic Tape Cartridge for Information Interchange - Helical RecordingISO/IEC 11319ECMA-169 (1992) 8
5、 mm Wide Magnetic Tape Cartridge - Dual Azimuth Format for Information Interchange -ISO/IEC 12246 Helical Scan RecordingECMA-246 (1996) 8 mm Wide Magnetic Tape Cartridges for Information Interchange - Helical Scan RecordingISO/IEC 15780 AIT-1 FormatECMA-247 (1996) 8 mm Wide Magnetic Tape Cartridges
6、for Information Interchange - Helical Scan RecordingISO/IEC 15718 HH-1 FormatECMA-249 (1996) 8 mm Wide Magnetic Tape Cartridge for Information Interchange - Helical Scan RecordingISO/IEC 15757 DA-2 FormatECMA-293 (1999) 8 mm Wide Magnetic Tape Cartridge for Information Interchange - Helical Scan Rec
7、ordingISO/IEC xxxxx MamouthTape-2 FormatECMA-291 (1999) 8 mm Wide Magnetic Tape Cartridges for Information Interchange - Helical Scan RecordingISO/IEC zzzzz AIT-1 With MIC FormatThis ECMA Standard specifies the use of a Memory In Cartridge chip. It provides a storage capacity of 50 Gbytesuncompresse
8、d user data with a tape of 230 m.This ECMA Standard has been contributed to ISO/IEC for adoption under the fast-track procedure as an InternationalStandard.This ECMA Standard has been adopted by the ECMA General Assembly of 16thDecember 1999.- i -Table of contentsSection 1 - General 11Scope 12 Confo
9、rmance 12.1 Magnetic tape cartridge 12.2 Generating drive 12.3 Receiving drive 13 References 24 Definitions 24.1 Absolute Frame Number (AFN) 24.2 a.c. erase 24.3 Access 24.4 algorithm 24.5 Area ID 24.6 Automatic Track Finding (ATF) 24.7 Average Signal Amplitude 24.8 azimuth 24.9 back surface 24.10 b
10、yte 24.11 cartridge 24.12 Channel bit 34.13 Codeword 34.14 Early Warning Point (EWP) 34.15 End of Data (EOD) 34.16 Entity 34.17 Error Correcting Code (ECC) 34.18 flux transition position 34.19 flux transition spacing 34.20 Frame 34.21 Housekeeping Frame 34.22 Logical Beginning of Tape (LBOT) 34.23 m
11、agnetic tape 34.24 Master Standard Amplitude Calibration Tape 34.25 Master Standard Reference Tape 34.26 Memory In Cartridge (MIC) 44.27 Partition Boundary 44.28 Physical Beginning of Tape (PBOT) 44.29 Physical End of Tape (PEOT) 44.30 physical recording density 44.31 pre-recording condition 44.32 p
12、rocessing 44.33 processed data 44.34 Processed Record 44.35 record 44.36 Reference Field 44.37 Secondary Standard Amplitude Calibration Tape 44.38 Secondary Standard Reference Tape 44.39 Separator Mark 54.40 Standard Reference Amplitude (SRA) 54.41 Tape Reference Edge 5- ii -4.42 Typical Field 54.43
13、 Standard Reference Current 54.44 Test Recording Current 54.45 track 54.46 unprocessed data 54.47 Unprocessed Record 55 Conventions and Notations 55.1 Representation of numbers 55.2 Names 56 Acronyms 57 Environment and safety 67.1 Test environment 67.2 Operating environment 67.3 Storage environment
14、67.4 Transportation 67.5 Safety 77.6 Flammability 7Section 2 - Requirements for the case 78 Dimensional and mechanical characteristics of the case 78.1 General 78.2 Overall dimension 88.3 Holding areas 88.4 Cartridge insertion 88.5 Window 98.6 Loading grips 98.7 Label areas 98.8 Datum areas and Datu
15、m holes 108.9 Support areas 118.10 Recognition holes 118.11 Write-inhibit hole 118.12 Pre-positioning surfaces 128.13 Cartridge lid 138.14 Cartridge reel lock 148.15 Reel access holes 158.16 Interface between the reels and the drive spindles 158.17 Light path 168.18 Position of the tape in the case
16、178.19 Tape path zone 178.20 Tape access cavity 178.21 Tape access cavity clearance 178.22 Requirements for the MIC 188.23 Recognition recesses 19Section 3 - Requirements for the unrecorded tape 399 Mechanical, physical and dimensional characteristics of the tape 399.1 Materials 399.2 Tape length 39
17、9.2.1 Length of magnetic tape 39- iii -9.2.2 Length of leader and trailer tapes 399.2.3 Length of the splicing tapes 399.3 Tape width 399.3.1 Width of magnetic, leader and trailer tapes 399.3.2 Width and position of the splicing tape 409.4 Discontinuities 409.5 Tape thickness 409.5.1 Thickness of th
18、e magnetic tape 409.5.2 Thickness of the leader and trailer tape 409.5.3 Thickness of the splicing tape 409.6 Longitudinal curvature 409.7 Cupping 409.8 Coating adhesion 409.9 Layer-to-layer adhesion 419.10 Tensile strength 419.10.1 Breaking strength 419.10.2 Yield strength 419.11 Residual elongatio
19、n 419.12 Electrical resistance of the recording surface 429.13 Tape winding 429.14 Light transmittance of the tape 429.15 Recognition stripe 4210 Magnetic recording characteristics 4310.1 Typical Field 4310.2 Signal Amplitude 4410.3 Resolution 4410.4 Overwrite 4410.5 Ease of erasure 4410.6 Tape qual
20、ity 4410.6.1 Missing pulses 4410.6.2 Missing pulse zone 4410.7 Signal-to-Noise Ratio (SNR) characteristic 45Section 4 - Requirements for an interchanged tape 4511 Format 4511.1 General 4511.2 Basic Groups 4511.2.1 Entity 4611.2.2 Group Information Table 4711.2.3 Block Access Table (BAT) 5011.3 Sub-G
21、roups 5211.3.1 G1 Sub-Group 5211.3.2 G2 Sub-Group - Randomizing 5311.3.3 G3 Sub-Group 5411.4 Data Block 5511.4.1 ID information 5511.4.2 Recording of the ID Information in the Data Block Headers 5712 Method of recording 6312.1 Physical recording density 64- iv -12.2 Long-term average bit cell length
22、6412.3 Short-term average bit cell length 6412.4 Rate of change 6412.5 Bit shift 6412.6 Read signal amplitude 6412.7 Maximum recorded levels 6413 Track geometry 6413.1 Track configuration 6413.2 Average track pitch 6513.3 Variations of the track pitch 6513.4 Track width 6513.5 Track angle 6513.6 Tra
23、ck edge straightness 6513.7 Track length 6513.8 Azimuth angles 6514 Recorded patterns 6614.1 Recorded Data Block 6614.2 Margin blocks 6615 Format of a track 6615.1 Track structure 6615.2 Positioning accuracy 6815.3 Tracking scheme 6816 Layout of the tape 6816.1 Device Area 6916.2 Reference Area 7016
24、.3 Position Tolerance Band No. 1 7016.4 System Area 7016.4.1 System Preamble 7016.4.2 System Log 7016.4.3 System Postamble 7416.4.4 Position Tolerance Band No. 2 7416.4.5 Vendor Group Preamble 7416.5 Data Area 7416.5.1 Vendor Group 7416.5.2 Recorded Data Group 7516.5.3 ECC3 7516.5.4 Multiple Recorde
25、d Instances 7616.5.5 Repeated Frames 7616.5.6 Appending and overwriting 7716.6 EOD Area 7816.7 Optional Device Area 7916.8 Logical End Of Tape (LEOT) 7916.9 Logical Beginning of Tape (LBOT) 7916.10 Early Warning Point - EWP 7916.11 Empty Partition 7916.12 Initialization 8017 Housekeeping Frames 8017
26、.1 Amble Frames 80- v -17.2 System Amble Frames 8018 Content of the MIC 81Annex A - Measurement of light transmittance 83Annex B - Measurement of Signal-to-Noise Ratio 87Annex C - Method for determining the nominal and the maximum allowable recorded levels89Annex D - Representation of 16-bit words b
27、y 20-Channel bits patterns 91Annex E - Measurement of bit shift 93Annex F - Method of measuring the straightness of track edges 95Annex G - ECC calculation 97Annex H - Recommendations for transportation 101Annex J - Read-After-Write 103Annex K - Example of the content of a Basic Group No. 0 105Annex
28、 L - Examples of chip 107- vi -.Section 1 - General1ScopeThis ECMA Standard specifies the physical and magnetic characteristics of an 8 mm wide magnetic tapecartridge containing a memory chip to enable physical interchange of such cartridges between drives. It alsospecifies the quality of the record
29、ed signals, the recording method and the recorded format - called AdvancedIntelligent Tape No.2 with Memory In Cartridge (AIT-2 with MIC) - thereby allowing data interchangebetween drives by means of such magnetic tape cartridges. The System Log are recorded in the MIC.This ECMA Standard specifies t
30、wo types of cartridge depending on the thickness of the magnetic tapecontained in the case.Information interchange between systems also requires, at a minimum, agreement between the interchangeparties upon the interchange code(s) and the specifications of the structure and labelling of the informati
31、on onthe interchanged cartridge.2 Conformance2.1 Magnetic tape cartridgeA tape cartridge shall be in conformance with this ECMA Standard if it meets all the mandatoryrequirements specified herein. The tape requirements shall be satisfied throughout the extent of the tape.2.2 Generating driveA drive
32、generating a magnetic tape cartridge for interchange shall be in conformance with this ECMAStandard if all recordings on the tape meet the mandatory requirements of this ECMA Standard, and ifeither or both methods of appending and overwriting are implemented. In addition, such a drive shall beable t
33、o record the System Log in the MIC.A claim of conformance shall state which of the following optional features are implemented and which arenot 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 conforma
34、nce shall state whether or not one, or more, registered algorithm(s) are implemented within the system and are able tocompress 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 Recei
35、ving driveA drive receiving a magnetic tape cartridge for interchange shall be in conformance with this ECMAStandard if it is able to handle any recording made on the tape according to this ECMA Standard. Inparticular it shall be able to read the System Log recorded in the MIC, be able to recognise
36、repeated frames, and to make available to the host, data and Separator Marks fromonly one of these frames; be able to recognise multiple representations of the same Basic Group, and to make available to thehost, data and Separator Marks from only one of these representations; be able to recognise an
37、 ECC3 frame, and ignore it if the system is not capable of using ECC3 checkbytes in a process of error correction; be able to recognise processed data within an Entity, identify the algorithm used, and make itsregistered identification number available to the host;- 2 - be able to make processed dat
38、a 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; whether or not one or more de-compression algorithm(s) are implemented within the system, and areable to be applied to compressed da
39、ta prior to making such data available to the host; the registered identification number(s) of the compression algorithm(s) for which a complementary de-compression algorithm is implemented.3 ReferencesECMA-287 (1999) Safety of electronic equipment.ISO/R 527:1966 Plastics - Determination of tensile
40、properties.ISO 1302:1992 Technical Drawings - Method of indicating surface texture on drawings.ISO/IEC 11576:1994 Information Technology - Procedure for the registration of algorithms for thelossless compression of data.4 DefinitionsFor the purposes of this ECMA Standard the following definitions ap
41、ply.4.1 Absolute Frame Number (AFN)A sequence number encoded in a Frame.4.2 a.c. eraseA process of erasure using magnetic fields of decaying intensity.4.3 AccessA read or write pass over a partition.4.4 algorithmA set of rules for transforming the logical representation of data.4.5 Area IDAn identif
42、ier defining the area of the tape and specifying the types of Frame written.4.6 Automatic Track Finding (ATF)The method by which tracking is achieved.4.7 Average Signal AmplitudeThe average peak-to-peak value of the output signal from the read head at the fundamental frequency of thespecified physic
43、al recording density over a minimum of 20,0 mm of track, exclusive of missing pulses.4.8 azimuthThe angular deviation made by the mean flux transition line with a line normal to the centreline of therecorded track.4.9 back surfaceThe surface of the tape opposite to the magnetic coating which is used
44、 to record data.4.10 byteAn ordered set of bits acted upon as a unit.4.11 cartridgeA case containing magnetic tape stored on twin hubs.- 3 -4.12 Channel bitThe elements by which, after modulation, the binary values ZERO and ONE are represented on tape bydifferent residual magnetisms.4.13 CodewordA w
45、ord generated by a compression algorithm. The number of bits in a Codeword is variable, and is notspecified by this ECMA Standard.4.14 Early Warning Point (EWP)A point along the length of the tape at which warning is given of the approach, in the forward direction oftape motion, of the Partition Bou
46、ndary or of the Physical End of Tape.4.15 End of Data (EOD)The point on the tape at the end of the group which contains the last user data.4.16 EntityA unit of recorded data, comprising an Entity Header and a Record sequence.4.17 Error Correcting Code (ECC)A mathematical computation yielding check b
47、ytes used for the detection and correction of errors.4.18 flux transition positionThat point which exhibits maximum free-space flux density normal to the tape surface.4.19 flux transition spacingThe distance along a track between successive flux transitions.4.20 FrameA pair of adjacent tracks with a
48、zimuths of opposite polarity, in which the track with the positive azimuthprecedes that with the negative azimuth.4.21 Housekeeping FrameA Frame which contains no user data and which is identified as such by the setting of the Data Fieldstherein.4.22 Logical Beginning of Tape (LBOT)The point along t
49、he length of the tape where a recording of data for interchange commences.4.23 magnetic tapeA tape which will accept and retain the magnetic signals intended for input, output and storage purposes oncomputers and associated equipment.4.24 Master Standard Amplitude Calibration TapeA pre-recorded tape on which the standard signal amplitudes have been recorded in the tracks of positiveand negative azimuth recorded at a track pitch of 11,0 m, on an a.c. erased tape.Note 1The tape includes recording at 2 053,6 ftpmm and 4 107,1 ftpmm.Note 2The Master Standard Amplitude Calibrat
