1、ECMA Standard ECMA-278 2“d Edition - June 2000 Standardising Information and Communication Systems Data Interchange on 12,7 mrn 128-Track Magnetic Tape Cartridge - Parallel Serpentine Format Phone: +41 22 849.60.00 - Fax: +41 22 849.60.01 - URL: http:/www.ecrna.ch - Internet: helpdeskecrna.ch ECMA S
2、tandard ECMA-278 June 2000 Standardising Information and Communication Systems Data Interchange on 12,7 rnrn 128-Track Magnetic Tape Cartridge - Parallel Serpentine Format Phone: +41 22 849.60.00 - Fax: +41 22 849.60.01 - URL: http:/www.ecrna.ch - Internet: helpdeskecrna.ch File: ECMA-278.DOC Brief
3、History Technical Committee ECMA TC17 has produced a series of ECMA Standards for magnetic tapes and magnetic tape cartridges containing tapes of different widths, e.g. 12,7 mm, 8 mm, 6,35 mm and 3,81 mm, almost all of which have been adopted by ISO/IEC under the fast-track procedure as ECMA Standar
4、ds. The series of such cartridges with a magnetic tape of 12,7 mm width and longitudinally recorded tracks comprises the following standards. ECMA-120 ISO/IEC 9661 ISO/IEC 11 559 ISO/IEC 13421 ISO/IEC 14251 ISO/IEC 13962 ISO/IEC 14833 ISO/IE C 153 O 7 ISO/IEC 15895 ISO/IEC 15896 ECMA-152 ECMA-182 EC
5、MA-196 ECMA-197 ECMA-209 ECMA-231 ECMA-258 ECMA-259 Data Interchange on 12,7 mm 1 %Track Magnetic Tape Cartridge Data Interchange on 12,7 mm 1 %Track Magnetic Tape Cartridge - Extended Format Data Interchange on 12,7 mm 48-Track Magnetic Tape Cartridge - DLT 1 Format Data Interchange on 12,7 mm 36-T
6、rack Magnetic Tape Cartridge Data Interchange on 12,7 mm 112-Track Magnetic Tape Cartridge - DLT 2 Format Data Interchange on 12,7 mm 128-Track Magnetic Tape Cartridge - DLT 3 Format Data Interchange on 12,7 mm 128-Track Magnetic Tape Cartridge - DLT 4 Format Data Interchange on 12,7 mm 128-Track Ma
7、gnetic Tape Cartridges - DLT 3-XT Format Data Interchange on 12,7 mm 208-Track Magnetic Tape Cartridges - DLT 5 Format This Standard ECMA-278 describes a cartridge containing a magnetic tape 12,7 mm wide and a recording format with an improved magnetic medium, 128 longitudinally recorded tracks, and
8、 a linear recording density of 3 400 bpmm. With a tape of 320 m, this format provides a native storage capacity of 10 Gbytes for user data, or with compressed data of typically 26 Gbytes. This ECMA Standard has been adopted as 2nd Edition of ECMA-278 by the ECMA General Assembly of June 2000. -I- Ta
9、ble of Contents Section 1 - General 1 1 2 2.1 2.2 2.3 3 4 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 4.10 4.11 4.12 4.13 4.14 4.15 4.16 4.17 4.18 4.19 4.20 4.21 4.22 4.23 4.24 4.25 4.26 4.27 4.28 4.29 4.30 4.3 1 4.32 4.33 4.34 4.35 4.36 4.37 4.38 Scope Conformance Magnetic tape cartridge Generating system
10、Receiving system References Definitions algorithm anhysteretic erase average signal amplitude azimuth back surface beginning of partition (BOP) beginning of tape (BOT) cartridge cyclic redundancy check (CRC) character end of tape (EOT error-correcting code (ECC) error-detecting code (EDC) File Mark
11、flux transition position flux transition spacing half-wrap logical block logical forward logical reverse magnetic tape mark tach count Master Standard Reference Tape physical recording density pre-record condition recorded e le me nt Reference Field resync character SDM set Secondary Standard Refere
12、nce Tape (SSRT) servo track Standard Reference Amplitude (SRA) Standard Reference Current (I,) Test Recording Current (Im ) track track group trailer Typical Field write equalisation 1 1 1 1 1 1 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 2 3 3 3 3 3 3 3 3 3 3 3 3 3 3 4 4 4 - II - 5 Conventions and notations
13、5.1 Representation of numbers 5.2 Dimensions 5.3 Names 5.4 Acronyms 6 Environment and safety 6.1 6.2 Cartridge operating environment 6.3 Cartridge storage environment 6.4 Safety Cartridge and tape testing environment. 6.4.1 Safeness 6.4.2 Flammability 6.5 Transportation Section 2 - Requirements for
14、the unrecorded tape 7 Mechanical and electrical requirements 7.1 Material 7.2 Tape length 7.3 Width 7.4 Total thickness 7.5 Base material thickness 7.6 Discontinuity 7.7 Longitudinal curvature 7.7.1 Requirement 7.7.2 Procedure 7.8 Out-of-Plane distortions 7.9 Cupping 7.9.1 Requirement 7.9.2 Procedur
15、e 7.1 O Coefficient of dynamic friction 7.1 O. 1 Requirements 7.10.2 Procedure 7.1 1 Coating adhesion 7.12 Layer-to-layer adhesion 7.12.1 Requirements 7.12.2 Procedure 7.13 Electrical resistance 7.13.1 Requirement 7.13.2 Procedure 7.14 Abrasivity 7.15 Friction characteristics after stress 7.15.1 Req
16、uirements 7.15.2 Procedure 7.16 Surface roughness 7.16.1 Requirement 7.16.2 Procedure 7.17 Inhibitor tape 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 7 7 7 7 8 8 8 9 9 9 10 10 10 10 10 10 11 11 I) Magnetic recording characteristics 8.1 Typical Field 8.2 Signal amplitude 8.3 Resolution 8.4 Broad-band signal-to-noi
17、se ratio (BBSNR) 8.4.1 Requirement 8.4.2 Procedure 9 Tape quality 9.1 Missing pulse 9.1.1 Requirement 9.1.2 Procedure 9.2 Coincident missing pulse 9.2.1 Requirement 9.2.2 Procedure 9.3 Missing pulse density 9.3.1 Requirement 9.3.2 Procedure 9.4 Tape durability Section 3 - Mechanical specifications o
18、f the tape cartridge 10 General 1 O. 1 Overall dimensions 10.2 Write-inhibit mechanism 10.3 10.4 10.5 Case opening 10.6 Locating notches 10.7 Locating areas (figure 8) 10.8 10.9 1 O. 1 O 10.11 Stacking ribs 10.12 Recessed area 10.13 Flexibility of the case Label areas of the rear side Label area on
19、the top side Inside configuration of the case around the case opening Other external dimensions of the case Central window 10.13.1 Requirements 1 O. 13.2 Procedure 10.14 Tape reel 10.14.1 Locking mechanism 10.14.2 10.14.3 Metallic insert 10.14.4 Toothed rim 10.14.5 Hub of the reel 10.14.6 Relative p
20、ositions 10.14.7 Axis of rotation of the reel Characteristics of the toothed rim 1 O. 15 Leader block 10.16 10.17 Latching mechanism 1 O. 18 Tape wind 10.19 Wind tension 10.20 Attachment of the tape to the leader block Circumference of the tape reel 11 11 11 11 11 11 12 12 12 12 12 13 13 13 13 13 13
21、 13 13 13 14 14 15 15 15 16 16 16 16 17 17 17 17 17 18 18 18 18 18 18 19 19 20 20 21 21 21 21 21 - iv - 10.21 Moment of inertia 1 O .22 Material 10.23 Cartridge identification notches 10.24 Finger slot Section 4 - Requirements for an interchanged tape 11 Method of recording 1 1.1 Physical recording
22、density 11.2 Bit cell length 11.3 Average bit cell length 11.3.1 1 1.3.2 Long-term average RLL bit cell length Short-term average RLL bit cell length 1 1.4 11.5 Bit shift 11.6 Total character skew 1 1.7 Missing zero-crossing zones 11.8 Coincident missing zero-crossing zones Rate of change of the sho
23、rt-term average RLL bit cell length 12 Servo tracks 12.1 12.2 12.3 12.4 Servo requirements 12.4.1 Servo amplitude 12.4.2 Servo azimuth 12.4.3 Servo errors 12.4.4 Servo edge spacing Locations of the servo tracks Physical width of the servo tracks Format of the servo tracks 12.5 Procedure 13 Data trac
24、k format 13.1 Number of data tracks 13.2 Track positions 13.3 Track width 13.4 Data azimuth 13.5 Half-wraps 14 Tape format 14.1 General 14.2 Recording area 14.3 Tach count 14.4 Physical blocks 14.5 Servo acquisition region 14.6 Volume control region 14.7 Data region 14.8 Data entities 15 Packet form
25、at 15.1 Packet header 15.2 Packet data 15.3 Packet trailer 16 Device blocks 16.1 Data device blocks 16.2 Mark device blocks 22 22 22 22 32 32 32 32 32 32 32 32 32 33 33 33 33 33 34 34 35 35 35 35 36 36 36 36 36 38 38 38 38 38 38 40 40 41 41 41 41 43 44 46 46 46 46 46 -v- 16.3 16.4 16.5 16.6 16.7 16.
26、8 16.9 16.10 16.11 File Mark Void mark Beginning of half-wrap mark End of half-wrap mark BOP mark EOD mark SDM mark FID mark DBM mark 16.1 1.1 16.1 1.2 16.1 1.3 DBM partitions packet 16.1 1.4 16.11.5 DBM File Mark packet DBM general information packet DBM wrap region packet DBM servo demark packet 1
27、6.12 SARS mark 16.13 DBM checked out mark 16.14 DBM valid mark 17 Device block format 17.1 Device block header 17.1.1 Device block control 17.1.2 Device block sequence control 17.1.3 Vendor identification code 17.2 Device block data 17.3 Device block trailer 18 ECC 18.1 CRC 18.2 Code block 18.3 ECC
28、encoded code block 18.4 Codeword correction code generation 18.5 MIE pointer code generation 18.6 ECC encoded interleave unit 18.7 Short error correction code generation 19 Recording of bytes on tape 19.1 Synchronisation format 19.2 Interblock gap formatting 19.3 RLL byte translation 19.4 Write equa
29、lisation bit translation 19.5 Writing bits on tape Annex A - Tape abrasivity measurement procedure Annex B - Media Type Label Annex C - Measurement of Bit Shift Annex D - Vendor Identification Code Annex E - Recommendations for transportation Annex F - Inhibitor tape Annex G - Tape durability 47 47
30、47 47 47 47 48 48 49 49 50 51 51 52 52 52 53 53 53 53 56 56 56 56 56 56 57 57 58 59 59 59 61 61 65 65 66 66 67 69 73 75 77 79 81 - vi - Section 1 - General 1 2 2.1 2.2 2.3 3 4 4.1 4.2 4.3 Scope This ECMA Standard specifies the physical and magnetic characteristics of a magnetic tape cartridge, using
31、 a magnetic tape 12,7 mm wide, so as to provide physical interchange of such cartridges between drives. It also specifies the quality of the recorded signals, the recording method and the recorded format known as Parallel Serpentine, thereby allowing data interchange between drives by means of such
32、cartridges. The format supports variable length Logical Records, high speed search, and the use of the algorithm for data compression specified in Standard ECMA-222. Information interchange between systems also requires, at a minimum, agreement between the interchange parties upon the interchange co
33、de(s) and the specification of the structure and labelling of the information on the interchanged cartridge. Together with a standard for volume and file structure, e.g. Standard ECMA-13, this ECMA Standard provides for full data interchange between data processing systems. Conformance Magnetic tape
34、 cartridge A tape cartridge shall be in conformance with this ECMA Standard if it meets all the mandatory requirements specified herein. The tape requirements shall be satisfied throughout the extent of the tape. Generating system A generating system shall be in conformance with this ECMA Standard i
35、f it generates a tape according to 2.1. Receiving system A receiving system shall be in conformance with this ECMA Standard if it can read all tapes according to 2.1. References ECMA-13: 1985 ECMA-222: 1996 ECMA-287: 1999 ISOR527: 1966 ISOIEC 646: 199 1 IS0 683-13:1986 ANSI MH10.8M-1993 File Structu
36、re and Labelling of Magnetic Tapes for Information Interchange Adaptive Lossless Data Compression Algorithm (ALDC) Safety of electronic equipment Plastics Determination of tensile properties Information technology - IS0 7-bit coded character set for information interchange Heat-treatable steels, all
37、oy steels and free-cutting steels - Part 13: Wrought stainless steels Materials Handling - Unit Loads and Transport Packages - Bar Code Symbols Definitions For the purpose of this ECMA Standard, the following definitions apply. algorithm A set of rules for transforming the logical representation of
38、data. anhysteretic erase A process of erasure utilising an alternating magnetic field of decaying level. average signal amplitude The average peak-to-peak value of the signal output measured over a minimum of 25,4 mm, exclusive of missing pulses. -2- 4.4 4.5 4.6 4.7 4.8 4.9 4.10 4.11 4.12 4.13 4.14
39、4.15 4.16 4.17 4.18 4.19 4.20 4.21 azimuth The angle, in minutes of arc, of the mean flux transition line of a track from a line normal to the tape Reference Edge. back surface The surface of the tape opposite the recording surface. beginning of partition (BOP) The point along the length of the tape
40、 where recording in any partition begins. beginning of tape (BOT) The point along the length of the magnetic tape, indicated by the start of recorded information. cartridge A container holding a single supply reel of magnetic tape with an attached leader block at the BOT end. cyclic redundancy check
41、 (CRC) character A four-byte character used for error detection. end of tape (EOT The point on a track farthest from BOT up to which recording is allowed. err or- c o rr e c tin g code (E C C) An algorithm yielding bytes used for error detection and correction. err or- d e t e c tin g cod e (ED C) A
42、n algorithm yielding bytes used for error detection. File Mark A recorded element requested by a host that marks the end of a host data file or aggregate. flux transition position The point on the magnetic tape that exhibits the maximum free-space flux density normal to the tape surface. flux transi
43、tion spacing The distance along a track between successive flux transitions. half-wrap A track group recorded in the physical forward or physical reverse direction. logical block User data or a File Mark that is received as input by the system or that is sent as output from the system. logical forwa
44、rd The direction of tape motion that results in finding an ascending order of device block identifiers. logical reverse The direction of tape motion that results in finding a descending order of device block identifiers. magnetic tape A tape that accepts and retains magnetic signals intended for inp
45、ut, output, and storage of data for information processing. mark tach count The value of the tach counter that exists at the starting point of an Interblock Gap prior to the fiist device block of a mark. 4.22 -3- Master Standard Reference Tape A tape selected as the standard for Reference Field, sig
46、nal amplitude, resolution, and broad-band signal-to-noise ratio. NOTE A Master Standard Reference Tape has been established at Imation Corporation. physical recording density The number of recorded flux transitions per unit length of track expressed in flux transitions per millimetre (ftpmm). pre-re
47、cord condition The condition of the magnetic tape in preparation for data recording that has been anhysteretically erased and subsequently servo written. recorded element A File Mark or a logical block. Reference Field The Typical Field of the Master Standard Reference Tape. resync character A contr
48、ol character identifying format resynchronisation points in a track. It is intended that read-back circuits be capable of resynchronising operations when such characters are sensed. SDM set The group of SDM marks delineated by the beginning and end SDM marks, containing any number of included middle
49、 SDM marks including zero middle SDM marks. Secondary Standard Reference Tape (SSRT) A tape, the performance of which is known and stated in relation to that of the Master Standard Reference Tape. NOTE Seconda y Standard Reference Tapes can be ordered from the Imation Corporation, 1 Imation Place, Oakdale, MN 55128-3414 under Part Number 84-9802-4185-9. In principle such tapes will be available for a period of 1 O years from the publication of this ECMA Standard. However, by agreement between ECMA and Imation Corporation, this period may be shortened or extended to take account of demands
