1、Standard ECMA-2862ndEdition - June 2000Standardizing Information and Communication SystemsPhone: +41 22 849.60.00 - Fax: +41 22 849.60.01 - URL: http:/www.ecma.ch - Internet: helpdeskecma.chData Interchange on 12,7 mm208-Track Magnetic TapeCartridges - DLT 6 Format.Standard ECMA-2862ndEdition - June
2、 2000Standardizing Information and Communication SystemsPhone: +41 22 840.60.00 - Fax: +41 22 849.60.01 - URL: http:/www.ecma.ch - Internet: helpdeskecma.chMB - 286-DOC - 03.07.00 14:01Data Interchange on 12,7 mm208-Track Magnetic TapeCartridges - DLT 6 Format.Brief HistoryTechnical Committee ECMA T
3、C17 has produced a series of ECMA Standards for magnetic tape cassettes and cartridges ofdifferent widths, e.g. 12,7 mm, 8 mm, 6,35 mm and 3,81 mm. In each series, the new standards correspond to specific types ofapplication and different user requirements. Enhanced and new media correspond also to
4、advancements in drive technology.The series of such cartridges with a magnetic tape of 12,7 mm width and longitudinally recorded tracks comprises thefollowing standards.ECMA-120 (1993) : Data Interchange on 12,7 mm 18-Track Magnetic Tape CartridgesISO 9661ECMA-152 (1993) : Data Interchange on 12,7 m
5、m 18-Track Magnetic Tape Cartridges - Extended FormatISO/IEC 11559ECMA-182 (1992) : Data Interchange on 12,7 mm 48-Track Magnetic Tape Cartridges - DLT 1 Format -ISO/IEC 13421ECMA-196 (1993) : Data Interchange on 12,7 mm 36-Track Magnetic Tape CartridgesISO/IEC 14251ECMA-197 (1993) : Data Interchang
6、e on 12,7 mm 112-Track Magnetic Tape Cartridges - DLT 2 Format -ISO/IEC 13962ECMA-209 (1994) : Data Interchange on 12,7 mm 128-Track Magnetic Tape Cartridges - DLT 3 FormatISO/IEC 14833ECMA-231 (1995) : Data Interchange on 12,7 mm 128-Track Magnetic Tape Cartridges - DLT 4 FormatISO/IEC 15305ECMA-25
7、8 (1997) : Data Interchange on 12,7 mm 128-Track Magnetic Tape Cartridges - DLT 3-XT FormatISO/IEC 15895ECMA-259 (1997) : Data Interchange on 12,7 mm 208-Track Magnetic Tape cartridge - DLT 5 FormatISO/IEC 15896ECMA-278(1998) : Data Interchange on 12,7 mm 128-track Magnetic Tape CartridgeISO/IEC 179
8、13 Parallel Serpentine FormatStandards ECMA-182, ECMA-197, ECMA-209, ECMA-231 and ECMA-259 concern a cartridge of a type different from thatof Standards ECMA-120, ECMA-152 or ECMA-196. Whilst the magnetic tape is also 12,7 mm wide, these standards arecharacterized by the fact that the physical track
9、s, recorded and read in pairs, constitute two groups, the first recorded and readin forward direction, the second in reverse direction. The capacity and performance of the first five DLT cartridges have beenimproved by raising the number of tracks from 48 in DLT 1 to 208 for DLT 5 and by using an im
10、proved magnetic tape inDLT 4 and DLT 5.The present ECMA Standard for the DLT 6 cartridge uses the same tape as DLT 4 and DLT 5. However, the recording densityand the tape speed specified in DLT 5 have been increased. As a result a native capacity of 40 Gbytes or, with compresseddata, of typically at
11、 least 80 Gbytes is achieved.All ECMA Standards listed above have been or will be adopted by ISO/IEC as ECMA Standards. The present ECMAStandard has also been contributed to ISO/IEC for adoption as an ECMA Standard under the fast-track procedure.Adopted as the 2ndedition of Standard ECMA-286 by the
12、General Assembly in June 2000.Table of contentsPage1Scope 12 Conformance 12.1 Magnetic tape cartridges 12.2 Generating systems 12.3 Receiving systems 13 References 14 Definitions 14.1 Average Signal Amplitude 14.2 azimuth 14.3 back surface 24.4 Beginning-Of-Tape marker (BOT) 24.5 block 24.6 byte 24.
13、7 cartridge 24.8 Cyclic Redundancy Check (CRC) character 24.9 Early Warning (EW) 24.10 Error-Detecting Code (EDC) 24.11 End-Of-Tape marker (EOT) 24.12 Entity 24.13 Error-Correcting Code (ECC) 24.14 Envelope 24.15 Envelope size 24.16 flux transition position 24.17 flux transition spacing 24.18 Group
14、Record 24.19 logical track 24.20 magnetic tape 24.21 Master Standard Reference Tape 34.22 object 34.23 page 34.24 physical recording density 34.25 physical track 34.26 Record 34.27 Reference Edge 34.28 Reference Field 34.29 Secondary Standard Reference Tape 34.30 Standard Reference Amplitude (SRA) 3
15、4.31 Standard Reference Current 34.32 Test Recording Current 34.33 Typical Field 35 Conventions and notations 45.1 Representation of numbers 45.2 Dimensions 45.3 Names 45.4 Acronyms 4- ii -6 Environment and safety 46.1 Cartridge and tape testing environment. 46.2 Cartridge operating environment 46.3
16、 Cartridge storage environment 56.4 Safety 56.4.1 Safeness 56.4.2 Flammability 56.5 Transportation 5Section 2 - Requirements for the unrecorded tape 57 Mechanical and electrical requirements 57.1 Material 57.2 Tape length 57.3 Width 57.4 Total thickness 57.5 Discontinuity 57.6 Longitudinal curvature
17、 67.6.1 Requirement 67.6.2 Procedure 67.7 Out-of-Plane distortions 67.8 Cupping 67.9 Roughness of the coating surfaces 67.9.1 Roughness of the back coating surface 67.9.2 Roughness of the magnetic coating surface 67.10 Coating adhesion 67.11 Layer-to-layer adhesion 77.11.1 Requirements 77.11.2 Proce
18、dure 77.12 Modulus of elasticity 87.12.1 Requirement 87.12.2 Procedure 87.13 Flexural rigidity 87.13.1 Requirement 87.13.2 Procedure 87.14 Tensile yield force 87.14.1 Procedure 97.15 Electrical resistance 97.15.1 Requirement 97.15.2 Procedure 97.16 Inhibitor tape 97.17 Abrasivity 97.17.1 Requirement
19、 97.17.2 Procedure 107.18 Light transmittance of the tape and the leader 107.19 Coefficient of dynamic friction 107.19.1 Requirements 107.19.2 Procedure for the measurement of the friction between the magnetic surface and the back surface 107.19.3 Procedure for the measurement of the friction betwee
20、n the magnetic surface or the back surface andcalcium titanate ceramic 11- iii -8 Magnetic recording characteristics 118.1 Typical Field 128.2 Signal amplitude 128.3 Resolution 128.4 Overwrite 128.4.1 Requirement 128.5 Peak shift 128.5.1 Requirement 128.5.2 Procedure 129 Tape quality 139.1 Missing p
21、ulses 139.1.1 Requirement 139.2 Missing pulse zone 139.2.1 Requirement 139.3 Tape durability 13Section 3 - Mechanical specifications of the tape cartridge 1310 General 1310.1 Bottom side and right side 1410.2 Back side and left side 1510.3 Tape reel 1510.4 Tape leader 1610.5 Front side 1710.6 Operat
22、ion of the cartridge 1810.7 Tape winding 1810.8 Moment of inertia 1910.9 Material 19Section 4 - Requirements for an interchanged tape 2811 Method of recording 2811.1 Physical recording density 2811.2 Channel bit cell length 2811.2.1 Average Channel bit cell length 2811.2.2 Long-term average Channel
23、bit cell length 2811.2.3 Short-term average Channel bit cell length 2811.3 Flux transition spacing 2811.4 Read signal amplitude 2811.5 Azimuth 2911.6 Channel skew 2912 Tape format 2912.1 Reference Edge 2912.2 Direction of recording 2912.3 Tape layout 2912.4 Calibration and Directory Area 2912.4.1 Sc
24、ratch Area 3012.4.2 Guard Area G1 3012.4.3 Calibration Tracks Area 3012.4.4 Guard Area G2 31- iv -12.4.5 Directory Area 3112.4.6 Guard Area G3 3112.5 Data Area 3112.5.1 Physical tracks 3212.5.2 Logical tracks 3413 Data format 3513.1 Data Bytes 3513.2 Data Blocks 3513.3 Types of Blocks 3613.4 Entitie
25、s 3613.5 Envelopes 3613.6 Block format 3613.6.1 Preamble 3713.6.2 Sync 3713.6.3 Data Field 3713.6.4 EDC 3813.6.5 Control Field 1 (CF1) 3913.6.6 Control Field 2 (CF2) 4013.6.7 CRC 4213.6.8 Postamble 4214 Use of blocks 4214.1 Data Blocks 4214.2 Filler Blocks 4214.3 End of Track Blocks (EOTR) 4214.4 En
26、d of Data Blocks (EOD) 4214.5 ECC Blocks 4215 Format of Entities 4216 Format of Envelopes 4317 Error handling 43Annex A - Measurement of light transmittance 45Annex B - Generation of the Data Block CRCs 49Annex C - ECC generation 51Annex D - Generation of page CRCs 55Annex E - Format of MAP entries
27、57Annex F - Format of Control Field 1 59Annex G - Format of Control Field 2 61Annex H - Recommendations for transportation 63Annex J - Inhibitor tape 65Annex K - Recommendations on tape durability 67Annex L - Handling guidelines 69Section 1 - General1ScopeThis ECMA Standard specifies the physical an
28、d magnetic characteristics of a 12,7 mm wide, 208-track magnetic tapecartridge, to enable physical interchangeability of such cartridges between drives. It also specifies the quality of therecorded signals, a format - called Digital Linear Tape 6 (DLT 6) - and a recording method, thereby allowing da
29、tainterchange between drives. Together with a labelling standard, for instance Standard ECMA-13 for Magnetic TapeLabelling, it allows full data interchange by means of such magnetic tape cartridges.2 Conformance2.1 Magnetic tape cartridgesA magnetic tape cartridge shall be in conformance with this E
30、CMA Standard if it satisfies all mandatoryrequirements of this Standard. The tape requirements shall be satisfied throughout the extent of the tape.2.2 Generating systemsA system generating a magnetic tape cartridge for interchange shall be in conformance with this ECMA Standard ifall the recordings
31、 that it makes on a tape according to 2.1 meet the mandatory requirements of this ECMAStandard.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 tocompress data received from the host prior to collectin
32、g the data into blocks, and the registered identification number(s) of the implemented compression algorithm(s) .2.3 Receiving systemsA system receiving a magnetic tape cartridge for interchange shall be in conformance with this ECMA Standard ifit is able to handle any recording made on a tape accor
33、ding to 2.1.In addition, it shall whether or not one, or more de-compression algorithm(s) are implemented within the system, and are able tobe applied to de-compress data prior to making such data available to the host, the registered identification number(s) of the implemented compression algorithm
34、(s) .3 ReferencesECMA-13 File structure and labelling of magnetic tapes for information interchange (1985)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 the losslesscompr
35、ession of data.4 DefinitionsFor the purpose of this ECMA Standard, the following definitions apply.4.1 Average Signal AmplitudeThe average peak-to-peak value of the output signal from the read head at the physical recording density of2 578 ftpmm measured over a minimum length of track of 25,4 mm, ex
36、clusive of missing pulses.4.2 azimuthThe angular deviation, in degrees of arc, of the mean flux transition line of the recording made on a track from aline normal to the Reference Edge.- 2 -4.3 back surfaceThe surface of the tape opposite the magnetic coating which is used to record data.4.4 Beginni
37、ng-Of-Tape marker (BOT)A hole punched on the centreline of the tape towards the end nearest to the leader.4.5 blockA set of contiguous bytes recorded on a physical track and considered as a unit.4.6 byteAn ordered set of bits acted upon as a unit.NOTEIn this ECMA Standard, all bytes are 8-bit bytes.
38、4.7 cartridgeA case containing a single supply reel of 12,7 mm wide magnetic tape with a leader attached at the outer end.4.8 Cyclic Redundancy Check (CRC) characterA 64-bit character, generated by a mathematical computation, used for error detection.4.9 Early Warning (EW)A signal generated by the d
39、rive indicating the approaching end of the recording area.4.10 Error-Detecting Code (EDC)A mathematical computation yielding check bytes used for error detection.4.11 End-Of-Tape marker (EOT)A hole punched on the centreline of the tape towards the end farthest from the leader.4.12 EntityA group of t
40、wenty blocks treated as a logical unit and recorded on a logical track, except Filler Blocks, if any.4.13 Error-Correcting Code (ECC)A mathematical computation yielding check bytes used for the correction of errors detected by the CRC and theEDC.4.14 EnvelopeA group of Entities.4.15 Envelope sizeThe
41、 number of Entities in an Envelope.4.16 flux transition positionThe point which exhibits the maximum free-space flux density normal to the tape surface.4.17 flux transition spacingThe distance on the magnetic tape between successive flux transitions.4.18 Group RecordA Record consisting of a series o
42、f Records of equal size.4.19 logical trackA group of four physical tracks that are written or read simultaneously.4.20 magnetic tapeA tape that accepts and retains magnetic signals intended for input, output, and storage purposes on computers andassociated equipment.- 3 -4.21 Master Standard Referen
43、ce TapeA tape selected as the standard for Reference Field, signal amplitude, resolution, peakshift, and overwritecharacteristics.NOTEThe Master Standard Reference Tape has been established by the Quantum Corporation.4.22 objectA Record or a page of type Tape Mark.4.23 pageA logical division of a bl
44、ock.4.24 physical recording densityThe number of recorded flux transitions per unit length of track, expressed in flux transitions per millimetre(ftpmm).4.25 physical trackA longitudinal area on the tape along which a series of magnetic signals can be recorded.4.26 RecordA collection of User Bytes,
45、the number of which is determined by the host.4.27 Reference EdgeThe bottom edge of the tape when viewing the magnetic coating of the tape with the BOT to the left and the EOTto the right of the observer.4.28 Reference FieldThe Typical Field of the Master Standard Reference Tape.4.29 Secondary Stand
46、ard Reference TapeA tape the characteristics of which are known and stated in relation to those of the Master Standard ReferenceTape.NOTESecondary Standard Reference Tapes can be ordered under Reference “SSRT/DLT4“from Quantum Corporation,333 South Street, Shrewsbury, Mass. 01545-4195, USA. It is in
47、tended that these be used for calibrating tertiaryreference tapes for routine calibration.In principle, these Secondary Standard Reference Tapes will be available for a period of 10 years from thepublication of the first version of this ECMA Standard. However, by agreement between ECMA and QuantumCo
48、rporation, this period may be changed to take into account the demand for such Secondary Standard ReferenceTapes.4.30 Standard Reference Amplitude (SRA)The Average Signal Amplitude from the Master Standard Reference Tape when it is recorded with the TestRecording Current at 2 578 ftpmm.4.31 Standard
49、 Reference CurrentThe current that produces the Reference Field.4.32 Test Recording CurrentThe current that is 1,1 times the Standard Reference Current.4.33 Typical FieldIn the plot of the Average Signal Amplitude against the recording field at the physical recording density of2 578 ftpmm, the minimum field that causes an Average Signal Amplitude equal to 95 % of the maximum AverageSignal Amplitude.- 4 -5 Conventions and notations5.1 Representation of numbersThe following conventions and notations apply in this ECMA Standard, unless otherwise stated. A me
