1、 STDOECMA ECMA-139-ENGL 1990 3404593 0032836 705 ECMA EUROPEAN COMPUTER MAN U PACTUBERS ASS OCIATIOIO STANDARD ECIMA439 3,81 mm WIDE MAGNETIC TAPE CARTRIDGE FOR INFORMATION INTERCHANGE - HELICAL SCAN RECORDING - DDS FORMAT June 1990 STD.ECMA ECMA-339-ENGL 3990 W 3404593 0032433 643 Free copies of th
2、is document are available from ECMA, European Computer Manufacturers Association 114 Rue du Rhne - CH-124 Geneva (Switzeriand) . I Phone: + 41 22 735 36 34 Fax: + 41 22 786 52 31 I I I STD-ECHA ECHA-139-ENGL 1990 3404593 0032818 588 ECMA EUROPEAN COMPUTER MANUFACTURERS ASSOCIATION STANDARD ECMA-139
3、3,Sl mm WIDE MAGNETIC TAPE CARTRIDGE FOR INFORMATION INTERCHANGE - HELICAL SCAN RECORDING - DDS FORMAT June 1990 BRIEF HISTORY ECMA have produced a series of ECMA Standards for cassettes and cartridges containing magnetic tapes of different width and characteristics. ECMA-34 (1976): Data Interchange
4、 on 3,81 mm Magnetic ,Tape Cassette (32 bpmm, Phase Encoded) Data Interchange on 6,30 mm Magnetic Tape Cartridge (63 bpmm, Phase Encoded) Recording at 252 ftpmm Data Interchange on 6,30 mm Magnetic Tape Cartridge Using NRZl Recording at 394 ftpmm - Streaming Mode Data Interchange on 12,7 mm 18-Track
5、 Magnetic Tape Cartridges ECMA-46 (1976): ECMA-79 (1985): Data Interchange on 6,30 mm Magnetic Tape Cartridge Using IMFM ECMA-98 (1985): ECMA-120 (1987): These media were designed for the digital recording of data for storage and processing in data processing systems. In recent years, other magnetic
6、 media, originally developed for audio and video applications have been considered for use in data processing applications for storage as weil as for information interchange. The recording method known as helical scan recording, together with new types of magnetic tapes, allows to achieve capacities
7、 of more than 1 gigabyte of user data. This ECMA Standard is the first of a series of ECMA Standards for such magnetic tape cartridges. A second standard for the same medium but for a different format as weil as a standard for an 8 mm wide magnetic tape cartridge are under development. This ECMA Sta
8、ndard has been contributed to IS0 for further processing as an IS0 International Standard under the fast-track procedure. Adopted as an ECMA Standard by the General Assembly of 28th June 1990. - STD-ECMA ECMA-139-ENGL L990 W 3404593 0032820 136 -i- Table of Contents Page SECTION 1 - GENERAL 1. SCOPE
9、 2. CONFORMANCE 2.1 Magnetic Tape Cartridge 2.2 Generating System 2.3 Receiving System 3. REFERENCES 4. DEFINITIONS 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 4.10 4.1 1 4.12 4.13 4.14 4.15 4.16 4.17 4.18 4.19 4.20 4.2 1 4.22 4.23 4.24 4.25 4.26 4.27 4.28 4.29 Absolute Frame Number (AFN) Automatic Track Fi
10、nding (ATF) Area ID Average Signal Amplitude Azimuth Back Surface Byte Cartridge Channel Bit Data Format ID Early Warning Point (EWP) End of Data (EOD) Error Correcting Code (ECC) Flux Transition Position Flux Transition Spacing Frame Housekeeping Frame Logical Beginning of Tape (LBOT) Magnetic Tape
11、 Master Standard Amplitude Calibration Tape Master Standard Reference Tape Optimum Recording Field Partition Boundary Physical Beginning of Tape (PBOT) Physical End of Tape (PEOT) Physical Recording Density Pre-recording Condition Record Reference Recording Field 1 1 1 1 2 2 2 2 2 2 2 2 2 2 2 2 2 2
12、2 2 3 3 3 3 3 3 3 3 3 3 3 4 4 4 4.30 4.31 4.32 4.33 4.34 4.35 4.36 4.37 STD-ECMA ECMA-139-ENGL 1990 3404593 0032821 O72 - ii - Secondary Standard Amplitude Calibration Tape Secondary Standard Reference Tape Separator Standard Reference Amplitude Tape Reference Edge Test Recording Current Track Virtu
13、al End of Tape (VEOT) 5. ENVIRONMENT AND SAFETY 5.1 Testing Environment 5.2 Operating Environment 5.3 Storage Environment 5.4 Transportation 5.5 Safety 5.6 Flammability SECTION II - REQUIREMENTS FOR THE CASE 6. DIMENSIONAL AND MECHANICAL CHARACTERISTICS OF THE CASE 6.1 6.2 6.3 6.4 6.5 6.6 6.7 6.8 Ge
14、neral Overall Dimensions (Fig. 6 and 7) Loading Grip (Fig. 6) Holding Areas (Fig. 6) Notches of the Lid (Fig. 5 and 8) Lid Dimensions (Fig. 6 to 8) Optical Detection of the Beginning and End of Tape (Fig. 9 and 12) Bottom Side (Fig. 10 and 1 I) 6.8.1 6.8.2 6.8.3 6.8.4 6.8.5 6.8.6 6.8.7 6.8.8 6.8.9 6
15、.8.1 O 6.8.1 1 Locking mechanism of the slider Access holes Recognition, Sub-datums, and Write-inhibit Holes Datum Holes Access room for tape guides Holes for accessing the hubs Internal structure of the lower half (Fig. 12) Light path (Fig. 12) Support Areas (Fig. 13) Datum Areas (Fig. 13) Relation
16、ship between Support and Datum Areas and Reference Plane Z (Fig. 14) 6.9 Hubs (Fig. 15, 16) 6.10 Leader and Trailer Attachment 6.1 1 6.12 6.13 6.14 Interface between the Hubs and the Drive Spindles (Fig. 17) Opening of the Lid (Fig. 18) Release of the Hub Locking Mechanism (Fig. 19, 20) Label Areas
17、(Fig. 21, 22) 5 6 6 9 10 10 12 12 12 13 14 14 14 14 15 15 15 15 16 16 STDmECMA ECMA-139-ENGL 1990 3404593 0032822 TO9 I iii - SECTION III - REQUIREMENTS FOR THE UNRECORDED TAPE 7. MECHANICAL, PHYSICAL AND DIMENSIONAL CHARACTERISTICS OF THE TAPE 7.1 Materials 7.2 Tape Length 7.2.1 Length of Magnetic
18、Tape 7.2.2 Length of Leader and Trailer Tapes 7.3 7.4 7.5 7.6 7.7 7.8 7.9 7.10 Tape Width Discontinuities Total Thickness Longitudinal Curvature Cupping Coating Adhesion Layer-to-Layer Adhesion Tensile Strength 7.10.1 Breaking Strength 7.10.2 Yield Strength 7.1 1 Residual Elongation 7.12 7.13 Light
19、Transmittance of Tape Electrical Resistance of Coated Surfaces 8. MAGNETIC RECORDING CHARACIERISTICS 8. I Optimum Recording Field 8.2 Signai Amplitude 8.3 Resol u tion 8.4 Overwrite 8.4.1 8.4.2 8.5 Ease of Erasure 8.6 Tape Quality Physical Recording Densities of 750,6 ftpmm and 3002 ftpmm Physical R
20、ecording Densities of 83,4 ftpmm and 1001 ftpmm 8.6.1 Missing Pulses 8.6.2 Missing Pulse Zone 8.7 Signal-to-Noise Ratio (SIN) Characteristic SECTION IV - REQUIREMENTS FOR AN INTERCHANGED TAPE 9. DDS FORMAT 9.1. General 9.2. Basic Groups 27 27 27 27 27 27 27 27 27 27 27 28 29 29 29 29 29 29 30 30 31
21、31 31 31 32 32 32 32 32 32 32 33 33 33 33 9.2. i Index 9.2.2 Block Access Table 34 37 9.3. G 1 Sub-Groups 9.3.1 Randomizing - G2 Sub-Group 9.3.2 G3 Sub-Group 9.3.3 Sub-Group G4 9.3.4 Main Data Block 9.4. Sub-Data Area 9.4.1 9.4.2 9.4.3 9.4.4 9.4.5 9.4.6 9.4.7 9.4.8 9.4.9 Pack Item No. 1 Pack Item No
22、. 2 Pack Item No. 3 Pack item No. 4 Pack Item No. 5 Pack Item No. 6 Pack Item No. 7 Pack item No. 8 Sub Data Block 10. METHOD OF RECORDING 10.1 Physical Recording Density 10.2 10.3 10.4 Rate of Change 10.5 Bit Shift 10.6 Read Signal Amplitude 10.7 Maximum Recorded Levels Long-Term Average Bit Cell L
23、ength Short-Term Average Bit Cell Length 11. TRACK GEOMETRY 11.1 Track Configuration 11.1.1 11.1.2 11.1.3 11.1.4 11.1.5 11.1.6 11.1.7 11.1.8 Average Track Pitch Variations of the track pitch Track Width Track Angle Track Edge linearity Track Length Ideal Tape Centreline Azimuth Angles 12. RECORDING
24、OF BLOCKS ON THE TAPE 12.1 Recorded Main Data Block 12.2 Recorded Sub Data Block 12.3 12.4 Spacer Blocks Margin Blocks, Preamble Blocks and Postamble Blocks 13. FORMAT OF A TRACK 39 40 40 42 46 48 48 49 50 51 52 53 54 55 55 65 65 65 65 65 65 65 65 65 65 66 66 66 66 67 67 67 67 67 67 67 67 67 68 13.1
25、 Track Capacity i 3.2 Positioning Accuracy 68 68 STDmECMA ECMA-337-ENGL 1770 3404573 0032824 883 -v- 13.3 Tracking Scheme 14. MAGNETIC TAPE LAYOUT 14.1 Device Area 14.2 Reference Area 14.3 14.4 System Area Position Tolerance Band No. 1 14.4. i System Preamble 14.4.2 System Log 14.4.3 System Postambl
26、e 14.4.4 14.4.5 Vendor Group Preamble Position Tolerance Band No. 2 14.5 Data Area 14.5.1 Vendor Group 14.5.2 Recorded Data Group 14.5.3 ECC3 14.5.4 Multiple Recorded Instances 14.5.5 Repeated Frames 14.5.6 Appending and Overwriting 14.6 EOD Area 14.7 Post-EOD Area 14.8 14.9 Initialization Early War
27、ning Point - EWP i 5. PARTITIONED TAPE 15.1 Overall Magnetic Tape Layout 15.1.1 Device Area 15.1.2 Partition 1 15.1.3 Partition O 15.2 Area-ID 15.3 15.4 Empty Partitions 15.5 Initialization of Partitioned Tapes System Area Pack Items No. 3 and No. 4 16. HOUSEKEEPING FRAMES 16.1 Amble Frames 16.2 Sys
28、tem Log Frames 16.3 Tape Management Frames SECTION V - APPENDICES APPENDIX A - Measurement of the Light Transmittance of the Prisms 68 71 72 72 72 72 72 72 72 72 73 73 73 73 73 74 74 75 77 77 77 77 78 78 78 78 79 79 79 79 80 80 80 80 80 81 83 APPENDIX B - Recognition Holes 85 - STD-ECMA ECMA-139-ENG
29、L 1990 H 3404593 0032825 718 H - vi - APPENDIX C - Means to Open the Lid APPENDIX D - Measurement of Light Transmittance of Tape and Leaders APPENDIX E - Measurement of Signal-to-Noise Ratio APPENDIX F - Method for Determining the Nominal and the Maximum Allowable Recorded Levels APPENDIX G - Repres
30、entation of 8-Bit Bytes by IO-Bit Patterns APPENDIX H - Measurement of Bit Shift APPENDIX J - Recommendations for Transportation APPENDIX K - Method of Measuring Track Edge Linearity APPENDIX L - Read-After-Write APPENDIX M - Example of the Content of a basic Group No. O 87 89 93 95 97 103 107 109 1
31、11 113 STD-ECMA ECMA-139-ENGL 1990 m 3404593 0032826 b54 m -I- SECTION l - GENERAL SCOPE This ECMA Standard specifies the physical and magnetic characteristics of a 3,81 mm wide magnetic tape cartridge to enable interchangeability of such cartridges. It also specifies the quality of the recorded sig
32、nal, the format and the recording method, thereby allowing data interchange by means of such magnetic tape cartridges. CONFORMANCE Magnetic Tape Cartridge A tape cartridge shall be in conformance with this Standard if it meets all mandatory require- ments specified herein. The tape shall be either a
33、 Single Data Space Tape or a Partitioned Tape. Generating System A system generating a magnetic tape cartridge for interchange shall be entitled to claim confor- mance with this Standard if all recordings on the tape meet the mandatory requirements of this Standard, and if either or both methods of
34、appending and overwriting are implemented. In addition a claim of conformance shall state which of the following optional features are implemented and which are not: - the performing of a Read-After-Write check and the recording of any necessary repeated frames, - the recording of multiple represent
35、ations of the same Basic Group, - the generation of ECC3 Frames. Receiving System A system receiving a magnetic tape cartridge for interchange shall be entitled to claim confor- mance with this Standard if it is able to handle any recording made on the tape according to this Standard. In particular
36、it shall be able: - to recognize repeated frames and to make available to the user data and separator marks from only one of these frames, to recognize multiple representations of the same Basic Group and to make available to the user data and separator marks from only one of these representations,
37、to recognize an ECC3 frame, and ignore it if the option specified below is not implemented, to update the System Log(s) if the Write-lnhibit Hole state so permits. - - - in addition a claim of conformance shall state whether or not the system is capable of using ECC3 check bytes in a process of erro
38、r correction. REFERENCES ECMA-129 IS0 1307 IS0 R 527 : Safety of Information Technology Equipment (ITE) : Technical Drawings - Method of indicating Surface Texture on Drawings : Plastics - Determination of tensile properties 4. DEFINITIONS For the purpose of this Standard, the following definitions
39、apply. 4.1 Absolute Frame Number (AFN) A sequence number, encoded in the frame. 4.2 Automatic Track Finding (ATF) The method by which tracking is achieved. 4.3 Area ID An identifier defining the area of the tape and specifying the types of frame written. 4.4 Average Signal Amplitude The average peak
40、-to-peak value of the output signal from the read head at the fundamental frequency of the specified physical recording density over a minimum of 7.8 mm of track, exclu- sive of missing pulses. 4.5 Azimuth The angular deviation, in degrees, minutes and seconds of arc, made by the mean flux transitio
41、n line with the line normal to the centreline of the recorded track. 4.6 Back Surface The surface of the tape opposite to the magnetic coating which is used to record data. 4.7 Byte An ordered set of bits acted upon as a unit. 4.8 Cartridge A case containing magnetic tape stored on twin hubs. 4.9 Ch
42、annel Bit A bit after 8-10 transformation. 4.10 Data Format ID An identifier specifying which data format is being used on the tape. 4.11 Early Warning Point (EWP) A point along the length of the tape at which warning is given of the approach, in the forward direction of tape motion, of the partitio
43、n boundary or of the Physical End of Tape. 4.12 End of Data (EOD) The point on the tape at the end of the group which contains the last user data. 4.13 Error Correcting Code (ECC) A mathematical algorithm yielding check bytes used for the detection and correction of errors. 4.14 Flux Transition Posi
44、tion That point which exhibits maximum free-space flux density normal to the tape surface. 4.15 Flux Transition Spacing The distance along a track between successive flux transitions. STD-ECMA ECMA-139-ENGL 1990 W 3404593 0032828 427 -3- 4.16 4.17 4.18 4.19 4.20 4.21 4.22 4.23 4.24 4.25 4.26 Frame A
45、 pair of adjacent tracks with azimuths of opposite polarity, in which the track with the positive azimuth precedes that with the negative azimuth. Housekeeping Frame A frame which contains no user data fields therein. Logical Beginning of Tape (LBOT) The point along the length of the tape Magnetic T
46、ape and which is identified as such by the values in the data where a recording of data for interchange commences. A tape which will accept and retain the magnetic signals intended for input, output and storage purposes on computers and associated equipment. Master Standard Amplitude Calibration Tap
47、e A pre-recorded tape on which the standard signal amplitudes have been recorded in the tracks of positive azimuth, 23.0 pm wide, at nominal track pitch, on an AC-erased tape. NOTE I The tape includes recordings made at 83,4 ftpmm, 333,6 ftpmm, 500,4 fipmm, IO01 fipmm and 1501 ftpmm. NOTE 2 The Mast
48、er Standard Amplitude Calibration Tape has been established by Sony Corporation. Master Standard Reference Tape A tape selected as the standard for Reference Recording Field, Signal Amplitude, Resolution, Overwrite and Signal-to-Noise Ratio. NOTE 3 The Masier Standard Reference Tape has been eslobli
49、shed by Sony Corporation. Optimum Recording Field In the plot of Average Signal Amplitude against the recording field at the physical recording density of 3002 ftpmm, the field that causes the maximum Average Signal Amplitude. Partition Boundary The point along the length of a magnetic tape at which Partition 1 ends and Partition O commences. Physical Beginning of Tape (PBOT) The point where the leader tape is joined to the magnetic tape. Physical End of Tape (PEOT) The point where the trailer tape is joined to the magnetic tape. Physical Recordi
copyright@ 2008-2019 麦多课文库（www.mydoc123.com）网站版权所有
备案/许可证编号：苏ICP备17064731号-1