1、ECMA ECMAr377 73 W 3404573 0037726 423 ECMA EUROPEAN COMPUTER MANUFACTURERS ASSOCIATION STANDARD ECMA - 197 DATA INTERCHANGE ON 12,7 mm 112-TRACK MAGNETIC TAPE CARTRIDGES - DLT 2 FORMAT - December 1993 ECMA ECMA*197 93 3404593 0017727 3bT = Free copies of this document are available from ECMA, Europ
2、ean Computer Manufacturers Association, 114 Rue du Me - CH-1204 Geneva (Switzeriand) Phone: 41 22 735 36 34 Fax: 41 22 786 52 31 X.400: C=ch. A=arcom, kma, Orgenevanet, OUl=ecma, S=helpdesk Internet helpdeskecmach ECHA ECMA*KL97 93 3404593 0017728 2Tb ECMA EUROPEAN COMPUTER MANUFACTURERS ASSOCIATION
3、 STANDARD ECMA = 197 DATA INTERCHANGE ON 12,7 mm 112-TRACK MAGNETIC TAPE CARTRIDGES - DLT 2 FORMAT - December 1993 ECMA ECMA*197 73 = 3404593 0017729 132 Brief History ECMA have produced a series of ECMA Standards for cassettes and cartridges containing magnetic tapes of different width and characte
4、ristics. ECMA-34 (1976) ECMA-46 (1976) : ECMA-79 (1985) : ECMA-98 (1985) : ECMA-120 (1993) : ECMA-139 (1990) : ECMA-145 (1990) : ECMA-146 (1990) : ECMA-150 (1991) ECMA-152 (1993) : ECMA-169 (1992) : ECMA-170 (1992) : ECMA-171 (1992) : ECMA-182 (1992) : ECMA-196 (1993) Data Interchange on 3,81 mm Mag
5、netic Tape Cassette (32 bpmm, Phase Encoded) Data Interchange on 6,30 mm Magnetic Tape Cartridge (63 bpmm, Phase Encoded) Data Interchange on 6,30 mm Magnetic Tape Cartridge Using IMFM Recording at 252 ftpmm Data Interchange on 6,30 mm Magnetic Tape Cartridge Using NRZ1 Recording at 394 ftpmm - Stre
6、aming Mode Data Interchange on 12,7 mm 18-Track Magnetic Tape Cartridges 3,81 mm Wide Magnetic Tape Cartridge for Information Interchange - Helical Scan Recording - DDS Format 8 mm Wide Magnetic Tape Cartridge for Information Interchange, Helical Scan Recording 3,8 1 mm Wide Magnetic Tape Cartridge
7、for Information Interchange - Helical Scan Recording - DATADAT Format 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 Edition Data Interchange on 12,7 mm 18-Track Magnetic Tape Cartridges - Extended Forma
8、t 8 mm Wide Magnetic Tape Cartridge, Dual Azimuth Format - Helical Scan Recording 3,81 mm Wide Magnetic Tape Cartridge for Information Interchange - Helical Scan Recording - DDS Format Using 60 m and 90 m Length Tapes 3,81 mm Wide Magnetic Tape Cartridge for Information Interchange - Helical Scan Re
9、cording - DATADAT-DC Format Using 60 m and 90 m Length Tapes Data Interchange on 12,7 mm 48-Track Magnetic Tape Cartridges - DLT 1 Format - Data Interchange on 12,7 mm 36-Track Magnetic Tape Cartridges Standard ECMA-182 concerns a cartridge of a type different from that of Standards ECMA-120 and ECM
10、A-152. Whilst the magnetic tape is also 12,7 mm wide, it is recorded on 48 physical tracks, and the format is different from these previous ECMA Standards. It is characterized by the fact that the physical tracks, recorded and read in pairs, constitute two groups, the first recorded and read in forw
11、ard direction, the second in reverse direction. This ECMA Standard constitutes a further development of the cartridge specified in Standard ECMA-182 in that the number of tracks has been raised from 48 to 112, thus raising the total capacity of the cartridge accordingly. Drives for DLT 2 cartridges
12、may be able to read from, and write onto, DLT 1 cartridges according to Standard ECMA-182. Adopted as an ECMA Standard by the General Assembly of December 1993. ECMA ECMA*l 93 3404593 0017730 95q -1- Table of contents Section 1 - General 1 Scope 2 Conformance 2.1 Magnetic tape cartridges 2.2 Generat
13、ing systems 2.3 Receiving systems 3 References 4 Definitions 4.1 Average Signal Amplitude 4.2 azimuth 4.3 back surface 4.4 Beginning-Of-Tape marker (BOT) 4.5 byte 4.6 cartridge 4.7 Cyclic Redundancy Check (CRC) character 4.8 Early Warning (EW) 4.9 Error-Detecting Code (EDC) 4.10 End-Of-Tape marker (
14、EOT) 4.11 Entity 4.12 Error-Correcting Code (ECC) 4.13 flux transition position 4.14 flux transition spacing 4.15 Logical Block 4.16 logical track 4.17 magnetic tape 4.18 Master Standard Reference Tape 4.19 object 4.20 physical block 4.21 physical recording density 4.22 physical track 4.23 Record 4.
15、24 Reference Edge 4.25 Reference Field 4.26 Secondary Standard Reference Tape 4.27 Standard Reference Amplitude (SRA) 4.28 Standard Reference Current 4.29 Test Recording Current 4.30 Typical Field Page 1 1 1 1 1 1 1 1 1 1 1 1 1 2 1 2 1 2 2 2 2 2 2 2 2 2 2 2 2 2 3 3 3 3 3 3 3 3 3 3 5 Conventions and
16、notations 5.1 Representation of numbers 5.2 Names 5.3 Acronyms 6 Environment and safety 6.1 Cartridge and tape testing environment. 6.2 Cartridge operating environment 6.3 Cartridge storage environment 6.4 Safety 6.4.1 Safeness 6.4.2 Flammability 6.5 Transportation Section 2 - Requirements for the u
17、nrecorded tape 7 Mechanical and electrical requirements 7.1 Material 7.2 Tape length 7.3 Width 7.4 Total thickness 7.5 Thickness of the base material 7.6 Thickness of the magnetic coating 7.7 Thickness of the back coating 7.8 Discontinuity 7.9 Longitudinal curvature 7.9.1 Requirement 7.9.2 Procedure
18、 7.10 Out-of-Plane distortions 7.11 Cupping 7.12 Roughness of the coating surfaces 7.12.1 Roughness of the back coating surface 7.12.2 Roughness of the magnetic coating surface 7.13 Coating adhesion 7.14 Layer-to-layer adhesion 7.14.1 Requirements 7.14.2 Procedure 7.15 Modulus of elasticity 7.15.1 R
19、equirement 7.15.2 Procedure 7.16 Flexural rigidity 7.16.1 Requirement 7.16.2 Procedure 3 3 4 4 4 5 5 5 5 5 6 6 6 6 6 6 6 7 7 7 7 9 9 9 9 9 9 - ECMA ECMA*L97 93 3404593 DOL7731 890 - ii ECMA ECMA*197 93 m 3404593 0037732 727 = - jii - 7.17 Tensile yield force 9 7.17.1 Procedure 9 7.18 Electrical resi
20、stance 7.18.1 Requirement 7.18.2 Procedure 7.19 Inhibitor tape 7.20 Abrasivity 7.20.1 Requirement 7.20.2 Procedure 7.21 Light transmittance of the tape and the leader 7.22 Coefficient of dynamic friction 9 9 10 10 10 10 10 11 11 7.22.1 Requirements 11 and the back surface 11 or the back surface and
21、calcium titanate ceramic 7.22.2 Procedure for the measurement of the friction between the magnetic surface 7.22.3 Procedure for the measurement of the friction between the magnetic surface 12 8 Magnetic recording characteristics 8.1 Typical Field 8.2 Signal amplitude 8.3 Resolution 8.4 Overwrite 8.4
22、.1 Requirement 8.5 Peak shift 8.5.1 Requirement 8.5.2 Procedure 9 Tape quality 9.1 Missing pulses 9.1.1 Requirement 9.2 Missing pulse zone 9.2.1 Requirement 12 12 13 13 13 13 13 13 13 14 14 14 14 14 9.3 Tape durability 14 Section 3 - Mechanical specifications of the tape cartridge 14 10 General 10.1
23、 Bottom side and right side (figures 8 and 9) 10.2 Back side and left side (figures 10 and 11) 10.3 Tape reel (figures 8, 12 and 13) 10.4 Tape leader (figures 14, 15 and 16) 10.5 Front side (figure 17) 10.6 Operation of the cartridge (figures 18 and 19) 14 15 16 17 17 19 19 ECHA ECHA*K197 93 3404593
24、 0037733 663 W - iv - 10.7 Tape winding 10.8 Moment of inertia 10.9 Material Section 4 - Requirements for an interchanged tape 11 Method of recording 1 1.1 Physical recording density 11.2 Bit cell length 11.2.1 Average bit cell length 11.2.2 Long-term average bit cell length 11.2.3 Short-term averag
25、e bit cell length 11.3 Flux transition spacing 11.4 Read signal amplitude 11.5 Azimuth 11.6 Channel skew 12 Tape format 12.1 Reference Edge 12.2 Direction of recording 12.3 Tape layout 12.4 Calibration and Directory Area 12.4.1 Scratch Area 12.4.2 Guard Area GI 12.4.3 Calibration Tracks Area 12.4.4
26、Guard Area G2 12.4.5 Directory Area 12.4.6 Guard Area G3 12.5 Data Area 12.5.1 Physical tracks 12.5.2 Width of the physical tracks 12.5.3 Logical tracks 12.5.4 Locations of the physical tracks 12.5.5 Layout of tracks in the Data Area 13 Data format 13.1 Data Bytes 13.2 Logical Blocks 13.3 Data Block
27、s 13.4 Types of Logical Blocks 13.5 Entities 13.6 Logical Block format 13.6.1 Preamble 13.6.2 Sync 13.6.3 Data Field 13.6.4 Control Field 1 (CFl) 13.6.5 Control Field 2 (CF2) 20 20 20 29 29 29 29 29 29 29 29 29 29 29 30 30 30 30 30 31 31 31 32 33 33 33 33 33 33 33 36 37 37 37 37 38 38 38 39 39 39 40
28、 41 ECMA ECMA*:L97 93 3404593 0037734 5TT -v- 13.6.6 CRC 13.6.7 Postamble 14 Use of Logical Blocks 14.1 Data Blocks 14.2 Tape Mark Blocks 14.3 Filler Blocks 14.4 End of Track Blocks (EOTR) 14.5 End of Data Blocks (EOD) 14.6 ECC Blocks 15 Format of Entities 16 Error handling Annexes A - Measurement o
29、f light transmittance B - CRC generation C - ECC generation D - Format of Control Field 1 E - Format of Control Field 2 F - Recommendations for transportation G - Inhibitor tape H - Recommendations on tape durability J - Handling guidelines 43 43 43 43 43 43 43 43 43 44 44 45 49 51 55 57 59 61 63 65
30、 ECMA ECMAa197 93 3404573 0017735 436 W Section 1 - General 1 2 2.1 2.2 2.3 3 4 4.1 4.2 4.3 4.4 4.5 Scope This ECMA Standard specifies the physical and magnetic characteristics of a 12,7 mm wide, 112-track magnetic tape cartridge, to enable interchangeability of such cartridges. It also specifies th
31、e quality of the recorded signals, a format - called Digital Linear Tape 2 (DLT 2) - and a recording method. Together with a labelling standard, e.g. Standard ECMA-13 for Magnetic Tape Labelling, it allows full data interchange by means of such magnetic tape cartridges. Conformance Magnetic tape car
32、tridges A magnetic tape cartridge shall be in conformance with this Standard if it satisfies all mandatory requirements of this Standard. The tape requirements shall be satisfied throughout the extent of the tape. Generating systems A system generating a magnetic tape cartridge for interchange shall
33、 be entitled to claim conformance with this Standard if all the recordings that it makes on a tape according to 2.1 meet the mandatory requirements of this Standard. Receiving systems A system receiving a magnetic tape cartridge for interchange shall be entitled to claim conformance with this Standa
34、rd if it is able to handle any recording made on a tape according to 2.1. References ECMA-13 (1985) IS0 1302: 1978 File Structure and Labelling of Magnetic Tapes for Information Interchange Technical drawings - Method of indicating surface texture on drawings. Definitions For the purpose of this Sta
35、ndard, the following definitions apply. Average Signal Amplitude The average peak-to-peak value of the output signal from the read head at the physical recording density of 1 674 ftpmm measured over a minimum length of track of 2S,4 mm, exclusive of missing pulses. azimuth The angular deviation, in
36、minutes of arc, of the mean flux transition line of the recording made on a track from the line normal to the Reference Edge. back surface The surface of the tape opposite the magnetic coating which is used to record data. Beginning-Of-Tape marker (BOT) A hole punched on the centreline of the tape t
37、owards the end nearest to the leader. byte An ordered set of bits acted upon as a unit. NOTE 1 In this Standard, ali bytes are is follows. i) The door shall have a movable lock the lower edge of which shall be at a distance I64 = 14,50 mm f 0.20 mm from reference plane A. A cam of the drive raises t
38、his lock in1 order to unlock the door which shall be unlocked when the edge is raised by 1,0 mm min. The door is then opened 90“ by the drive. It shrill be able to rotate further up to 105“. In the open position of the door the whole back side shall be accessible except the part limited by e65 = 35.
39、79 mm f 0,20 mm. In this position the space along the left side that is delimited by e66 = 457 mm f 0,lO mm shall be free for a drive element to contact the edge defined by l26 and I, (see figure 11). ii) A finger of the drive penetrates into the case through the window defined by P, to e25 (see fig
40、ure IO) to partially unlock the reel. The corresponding part of the locking mechanism shall not require a penetration other than 8 mm f 1 mm nor a force other than 3,3 N k 0,4 N to be actuated. iii) When the cartridge has been completely introduced into the drive, it is held in position by elements
41、of the drive engaging the positioning notch of the rig.ht side (figures 8 and 9) and the positioning hole in the bottom side (figure 8). ECMA ECMA*19 93 = 3Y04593 0017754 398 m - 20 - A second finger of the drive penetrates through the window of the bottom side defined by I, to I, and completely unl
42、ocks the reel. The requirements for penetration and force are the same as specified in ii) for the first finger. The drive spindle engages the teeth of the hub and raises the reel into the operating position (see figure 13). The force with which the tape reel is held against the spindle shall be 6,O
43、 N f 0,5 N. In this final position of the cartridge within the drive, the tip of the leader shall be positioned as specified by i v) v) I, = 4,42 mm f 1,52 mm e68 = 49,28 mm f 1,27 mm as shown in figures 18 and 19. When the cartridge is within the drive in the operating position (figures 13 and 19),
44、 the tape is pulled out of the cartridge by a drive leader attached to the hub of a reel within the drive. The tip of this drive leader is designed so as to match the shape of the main hole of the tape leader and to engage it. This drive leader has a hole corresponding to that shown in detail B of f
45、igure 16. Dimensions and positions of these two holes are such that when the tape leader is wound onto the hub of the drive reel the connection of the two leaders lies between the two holes. The tape leader has a stop edge the longitudinal position of which relative to the end of the main hole is sp
46、ecified by 140 (figure 16). The case shall have an abutment against which this stop edge comes to rest when the tape is completely pulled back into the cartridge. This abutment, together with a case element engaging the slot of the tape leader shall be such that the dimensional requirements for I, a
47、nd I68 are met. The tape leader and the abutment shall withstand the impact of having to stop the full reel when the tape leader is retracted with a speed in the range 152 mm/s to 178 mm/s. Until the reel is fully locked, i.e. until the cartridge is ejected from the drive, the stop edge shall be hel
48、d against the abutment with a force in the range 1.1 N to 1.7 N. vi) 10.7 Tape winding The tape shall be wound on the hub with the magnetic coating facing inwards, so that during forward reawwrite operation the tape is unwound from the cartridge reel in a counterclockwise direction when viewed from
49、the top of the cartridge. The tape shall be wound with a tension of 1.1 1 N f 0.28 N. 10.8 Moment of inertia A full reel of tape shall have a diameter between 87.45 mm and 91,19 mm. The moment of inertia shall be: - Full reel: Between 131 x lo-, gam2 and 160 x lo-, gm2 - Empty reel: Between 19 x IO-, g.m2 and 23 x lo-, g.m2 10.9 Material The cartridge can be made of any material as long as the requirements of this Standard are met. For example, the hub and the case could be made of 10% glass-filled polycarbonate. A typical wall thickness is 1,5 mm. The tape leader shall be made of
