1、Standard ECMA-231December 1995Standardizing 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 mm128-Track Magnetic TapeCartridges - DLT 4 FormatStandard ECMA-231December 1995Standardizing
2、Information and Communication SystemsPhone: +41 22 840.60.00 - Fax: +41 22 849.60.01 - URL: http:/www.ecma.ch - Internet: helpdeskecma.chMB - ECMA-231.doc - 13.02.96 17,10Data Interchange on 12,7 mm128-Track Magnetic TapeCartridges - DLT 4 FormatBrief HistoryECMA have produced a series of ECMA Stand
3、ards for cassettes and cartridges containing magnetic tapes of different widthand characteristics.ECMA-34 (1976) : Data Interchange on 3,81 mm Magnetic Tape Cassette (32 bpmm, Phase Encoded)ECMA-46 (1976) : Data Interchange on 6,30 mm Magnetic Tape Cartridge (63 bpmm, Phase Encoded)ECMA-79 (1985) :
4、Data Interchange on 6,30 mm Magnetic Tape Cartridge Using IMFM Recording at 252 ftpmmECMA-98 (1985) : Data Interchange on 6,30 mm Magnetic Tape Cartridge Using NRZ1 Recording at 394 ftpmm -Streaming ModeECMA-120 (1993) : Data Interchange on 12,7 mm 18-Track Magnetic Tape CartridgesECMA-139 (1990) :
5、3,81 mm Wide Magnetic Tape Cartridge for Information Interchange - Helical Scan Recording -DDS FormatECMA-145 (1990) : 8 mm Wide Magnetic Tape Cartridge for Information Interchange, Helical Scan RecordingECMA-146 (1990) : 3,81 mm Wide Magnetic Tape Cartridge for Information Interchange - Helical Sca
6、n Recording -DATA/DAT FormatECMA-150 (1991) : 3,81 mm Wide Magnetic Tape Cartridge for Information Interchange - Helical Scan Recording -DDS-DC Format Using 60 m and 90 m Length Tapes, 2nd EditionECMA-152 (1993) : Data Interchange on 12,7 mm 18-Track Magnetic Tape Cartridges - Extended FormatECMA-16
7、9 (1992) : 8 mm Wide Magnetic Tape Cartridge, Dual Azimuth Format - Helical Scan RecordingECMA-170 (1992) : 3,81 mm Wide Magnetic Tape Cartridge for Information Interchange - Helical Scan Recording -DDS Format Using 60 m and 90 m Length TapesECMA-171 (1992) : 3,81 mm Wide Magnetic Tape Cartridge for
8、 Information Interchange - Helical Scan Recording -DATA/DAT-DC Format Using 60 m and 90 m Length TapesECMA-182 (1992) : Data Interchange on 12,7 mm 48-Track Magnetic Tape Cartridges - DLT 1 Format -ECMA-196 (1993) : Data Interchange on 12,7 mm 36-Track Magnetic Tape CartridgesECMA-197 (1993) : Data
9、Interchange on 12,7 mm 112-Track Magnetic Tape Cartridges - DLT 2 Format -ECMA-198 (1993) : 3,81 mm Wide Magnetic Tape Cartridge for Information Interchange - Helical Scan Recording -DDS-2 Format using 120 m Length TapesECMA-209 (1994) : Data Interchange on 12,7 mm 128-Track Magnetic Tape Cartridges
10、 - DLT 3 FormatECMA-210 (1995) : 12,65 mm Wide Magnetic Tape Cartridge for Information Interchange - Helical Scan Recording -DATA-D3-1 FormatStandard ECMA-182 concerns a cartridge of a type different from that of Standards ECMA-120, ECMA-152 and ECMA-196. Whilst the magnetic tape is also 12,7 mm wid
11、e, it is characterized by the fact that the physical tracks, recorded and readin pairs, constitute two groups, the first recorded and read in forward direction, the second in reverse direction. StandardECMA-197 constitutes a development of the cartridge specified in Standard ECMA-182 in that the num
12、ber of tracks has beenraised from 48 to 112, thus raising the total capacity of the cartridge accordingly. Both Standards ECMA-182 and ECMA-197 have been adopted by ISO/IEC under the fast-track procedure as International Standards ISO/IEC 13421 and ISO/IEC13962, respectively. In Standard ECMA-209 th
13、e number of tracks is raised to 128 and an enhanced format is specified. ThisECMA Standard has also been contributed to ISO/IEC for adoption as an International Standard.This ECMA Standard specifies a further development of the DLT-formatted cartridges according to Standard ECMA-209allowing for a ca
14、pacity of 20 Gbytes of uncompressed data or, typically, of 40 Gbytes to 60 Gbytes of compressed user data.Adopted as an ECMA Standard by the General Assembly of December 1995.iTable of contentsPageSection 1 - General 11 Scope2 Conformance 12.1 Magnetic tape cartridges 12.2 Generating systems 12.3 Re
15、ceiving systems 13 References 14 Definitions 14.1 Average Signal Amplitude 14.2 azimuth 14.3 back surface 14.4 Beginning-Of-Tape marker (BOT) 14.5 byte 14.6 cartridge 24.7 Cyclic Redundancy Check (CRC) character 24.8 Early Warning (EW) 24.9 Error-Detecting Code (EDC) 24.10 End-Of-Tape marker (EOT) 2
16、4.11 Entity 24.12 Error-Correcting Code (ECC) 24.13 flux transition position 24.14 flux transition spacing 24.15 Logical Block 24.16 logical track 24.17 magnetic tape 24.18 Master Standard Reference Tape 24.19 object 24.20 page 24.21 physical block 24.22 physical recording density 24.23 physical tra
17、ck 34.24 Record 34.25 Reference Edge 34.26 Reference Field 34.27 Secondary Standard Reference Tape 34.28 Standard Reference Amplitude (SRA) 34.29 Standard Reference Current 34.30 Test Recording Current 34.31 Typical Field 35 Conventions and notations 35.1 Representation of numbers 35.2 Dimensions 4i
18、i5.3 Names 45.4 Acronyms 46 Environment and safety 46.1 Cartridge and tape testing environment. 46.2 Cartridge operating environment 46.3 Cartridge storage environment 46.4 Safety 56.4.1 Safeness 56.4.2 Flammability 56.5 Transportation 5Section 2 - Requirements for the unrecorded tape 57 Mechanical
19、and electrical requirements 57.1 Material 57.2 Tape length 57.3 Width 57.4 Total thickness 57.5 Discontinuity 57.6 Longitudinal curvature 57.6.1 Requirement 57.6.2 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
20、 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 Procedure 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 97.1
21、4.1 Procedure 97.15 Electrical resistance 97.15.1 Requirement 97.15.2 Procedure 97.16 Inhibitor tape 97.17 Abrasivity 107.17.1 Requirement 107.17.2 Procedure 107.18 Light transmittance of the tape and the leader 107.19 Coefficient of dynamic friction 10iii7.19.1 Requirements 107.19.2 Procedure for t
22、he measurement of the friction between the magnetic surface and the back surface 117.19.3 Procedure for the measurement of the friction between the magnetic surface or the back surface andcalcium titanate ceramic 118 Magnetic recording characteristics 118.1 Typical Field 128.2 Signal amplitude 128.3
23、 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 pulses 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 Gener
24、al 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 Operation of the cartridge 1810.7 Tape winding 1910.8 Moment of inertia 1910.9 Material 19Section 4 - Requirements for an interchanged tape 2811 Method of recording 2811.1
25、 Physical recording density 2811.2 Channel bit cell length 2811.2.1 Average Channel bit cell length 2811.2.2 Long-term average Channel 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 29
26、12 Tape format 29iv12.1 Reference Edge 2912.2 Direction of recording 2912.3 Tape layout 2912.4 Calibration and Directory Area 2912.4.1 Scratch Area 3012.4.2 Guard Area G1 3012.4.3 Calibration Tracks Area 3012.4.4 Guard Area G2 3112.4.5 Directory Area 3112.4.6 Guard Area G3 3112.5 Data Area 3112.5.1
27、Physical tracks 3212.5.2 Width of the physical tracks 3212.5.3 Logical tracks 3212.5.4 Locations of the physical tracks 3212.5.5 Layout of tracks in the Data Area 3313 Data format 3413.1 Data Bytes 3413.2 Logical Blocks 3413.3 Data Blocks 3413.4 Types of Logical Blocks 3513.5 Entities 3513.6 Logical
28、 Block format 3513.6.1 Preamble 3613.6.2 Sync 3613.6.3 Data Field 3613.6.4 EDC 3813.6.5 Control Field 1 (CF1) 3813.6.6 Control Field 2 (CF2) 4013.6.7 CRC 4113.6.8 Postamble 4114 Use of Logical Blocks 4114.1 Data Blocks 4114.2 Filler Blocks 4114.3 End of Track Blocks (EOTR) 4114.4 End of Data Blocks
29、(EOD) 4114.5 ECC Blocks 4115 Format of Entities 4116 Error handling 42AnnexesA - Measurement of light transmittance 43B - Generation of the Data Blocks CRCs 47C - ECC generation 49D - Generation of page CRCs 53E - Format of MAP entries 55vF - Format of Control Field 1 57G - Format of Control Field 2
30、 59H - Recommendations for transportation 61J - Inhibitor tape 63K - Recommendations on tape durability 65L - Handling guidelines 67Section 1 - General1 ScopeThis ECMA Standard specifies the physical and magnetic characteristics of a 12,7 mm wide, 128-track magnetictape cartridge, to enable intercha
31、ngeability of such cartridges. It also specifies the quality of the recorded signals, aformat - called Digital Linear Tape 4 (DLT 4) - and a recording method. Together with a labelling standard, forinstance Standard ECMA-13 for Magnetic Tape Labelling, it allows full data interchange by means of suc
32、h magnetictape cartridges.2 Conformance2.1 Magnetic tape cartridgesA magnetic tape cartridge shall be in conformance with this Standard if it satisfies all mandatory requirements ofthis Standard. The tape requirements shall be satisfied throughout the extent of the tape.2.2 Generating systemsA syste
33、m generating a magnetic tape cartridge for interchange shall be entitled to claim conformance with thisStandard if all the recordings that it makes on a tape according to 2.1 meet the mandatory requirements of thisStandard.2.3 Receiving systemsA system receiving a magnetic tape cartridge for interch
34、ange shall be entitled to claim conformance with thisStandard if it is able to handle any recording made on a tape according to 2.1.3 ReferencesECMA-13 (1985) File Structure and Labelling of Magnetic Tapes for Information InterchangeISO 1302:1992 Technical drawings - Method of indicating surface tex
35、ture on drawings.4 DefinitionsFor the purpose of this 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 142 ftpmm measured over a minimum length of track of 25,4 mm, exclu
36、sive of missing pulses.4.2 azimuthThe angular deviation, in minutes of arc, of the mean flux transition line of the recording made on a track fromthe line normal to the Reference Edge.4.3 back surfaceThe surface of the tape opposite the magnetic coating which is used to record data.4.4 Beginning-Of-
37、Tape marker (BOT)A hole punched on the centreline of the tape towards the end nearest to the leader.4.5 byteAn ordered set of bits acted upon as a unit.NOTEIn this Standard, all bytes are 8-bit bytes.- 2 -4.6 cartridgeA case containing a single supply reel of 12,7 mm wide magnetic tape with a leader
38、 attached at the outer end.4.7 Cyclic Redundancy Check (CRC) characterA 64-bit character, generated by a mathematical computation, used for error detection.4.8 Early Warning (EW)A signal generated by the drive indicating the approaching end of the recording area.4.9 Error-Detecting Code (EDC)A mathe
39、matical computation yielding check bytes used for error detection.4.10 End-Of-Tape marker (EOT)A hole punched on the centreline of the tape towards the end farthest from the leader.4.11 EntityA group of ten Logical Blocks treated as a logical unit and recorded on a logical track.4.12 Error-Correctin
40、g Code (ECC)A mathematical computation yielding check bytes used for the correction of errors detected by the CRC and theEDC.4.13 flux transition positionThe point which exhibits the maximum free-space flux density normal to the tape surface.4.14 flux transition spacingThe distance on the magnetic t
41、ape between successive flux transitions.4.15 Logical BlockThe two physical blocks simultaneously written on, or read from, the two physical tracks of a logical track.4.16 logical trackA pair of physical tracks that are written or read simultaneously.4.17 magnetic tapeA tape that accepts and retains
42、magnetic signals intended for input, output, and storage purposes on computersand associated equipment.4.18 Master Standard Reference TapeA tape selected as the standard for reference field, signal amplitude, resolution, peakshift, and overwritecharacteristics.NOTEThe Master Standard Reference Tape
43、has been established by the Quantum Corporation.4.19 objectA Record or a Tape Mark Block.4.20 pageA logical division of a physical block.4.21 physical blockA set of contiguous bytes recorded on a physical track and considered as a unit.4.22 physical recording densityThe number of recorded flux trans
44、itions per unit length of track, expressed in flux transitions per millimetre(ftpmm).- 3 -4.23 physical trackA longitudinal area on the tape along which a series of magnetic signals can be recorded.4.24 RecordA collection of User Bytes, the number of which is determined by the host.4.25 Reference Ed
45、geThe 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.4.26 Reference FieldThe Typical Field of the Master Standard Reference Tape.4.27 Secondary Standard Reference TapeA tape the characteristics of which are known
46、 and stated in relation to those of the Master Standard ReferenceTape.NOTESecondary Standard Reference Tapes can be ordered under Reference “SSRT/DLT4“ until the year 2005 fromQuantum Corporation, 333 South Street, Shrewsbury, Mass. 01545-4195, USA.It is intended that these be used for calibrating t
47、ertiary reference tapes for routine calibration.4.28 Standard Reference Amplitude (SRA)The Average Signal Amplitude from the Master Standard Reference Tape when it is recorded with the TestRecording Current at 1 071 ftpmm.4.29 Standard Reference CurrentThe current that produces the Reference Field.4
48、.30 Test Recording CurrentThe current that is 1,1 times the Standard Reference Current.4.31 Typical FieldIn the plot of the Average Signal Amplitude against the recording field at the physical recording density of2 142 ftpmm, the minimum field that causes an Average Signal Amplitude equal to 95 % of
49、 the maximumAverage Signal Amplitude.5 Conventions and notations5.1 Representation of numbersThe following conventions and notations apply in this Standard, unless otherwise stated. A measured value is rounded off to the least significant digit of the corresponding specified value. It impliesthat a specified value of 1,26 with a positive tolerance +0,01, and a negative tolerance -0,02 allows a range ofmeasured values from 1,235 to 1,275. In each block and in each field the bytes shall be arranged with Byte 1, the least significant, first.Within each byte the b
