ECMA 147 : 1ED 90

SECTION I - GENERAL
1 SCOPE AND CONFORMANCE
   1.1 Scope
   1.2 Conformance
2 REFERENCES
3 DEFINITIONS
   3.1 Average Signal Amplitude
   3.2 Case
   3.3 Direction of Rotation
   3.4 Eraseability
   3.5 Formatting
   3.6 Hub
   3.7 In-Contact
   3.8 Index
   3.9 Initialization
   3.10 Line of Access
   3.11 Liner
   3.12 Master Standard Reference Flexible Disk Cartridge
   3.13 Recording Disk
   3.14 Reference Erase Field
   3.15 Reference Field
   3.16 Secondary Standard Reference Flexible Disk
        Cartridge
   3.17 Shutter
   3.18 Side
   3.19 Standard Reference Amplitude
   3.20 Test Erase Current
   3.21 Test Recording Current
   3.22 Typical Field
4 GENERAL DESCRIPTION
   4.1 Drawings
   4.2 Main Elements
   4.3 Description
SECTION II - ENVIRONMENTS, MECHANICAL AND PHYSICAL
             CHARACTERISTICS
5 GENERAL REQUIREMENTS
   5.1 Environment and Transportation
        5.1.1 Testing environment
        5.1.2 Operating environment
        5.1.3 Storage environment
        5.1.4 Transportation
   5.2 Materials
        5.2.1 Case
        5.2.2 Liner
        5.2.3 Disk
        5.2.4 Hub
6 DIMENSIONAL CHARACTERISTICS
   6.1 Case
        6.1.1 Shape (Fig. 7)
        6.1.2 Thickness
        6.1.3 Hub access hole (Fig. 7)
        6.1.4 Locating holes (Fig. 7 and 9)
        6.1.5 Label area
        6.1.6 Head windows (Fig. 9)
        6.1.7 Write-inhibit hole (Fig. 8)
        6.1.8 Identification hole (Fig. 7 and 8)
        6.1.9 Profile of the shutter edge of the case (Fig.
               7 and 9)
        6.1.10 Shutter (Fig. 8 and 9)
   6.2 Liner
   6.3 Disk (Fig. 10)
        6.3.1 Diameter
        6.3.2 Thickness
   6.4 Hub (Fig. 10)
        6.4.1 Dimensions
        6.4.2 Hub orientation holes (Fig. 10)
   6.5 Optional Handling Notches (Fig. 7 and 8)
   6.6 Interface between Cartridge and Drive
   6.7 Compliance
7 PHYSICAL CHARACTERISTICS
   7.1 Flammability
   7.2 Coefficient of Linear Thermal Expansion of the Disk
   7.3 Coefficient of Linear Hygroscopic Expansion of the
        Disk
   7.4 Torque
        7.4.1 Starting torque
        7.4.2 Running torque without heads loaded
SECTION III - UNRECORDED FLEXIBLE DISK CARTRIDGE
8 MAGNETIC CHARACTERISTICS
   8.1 Recording Area
   8.2 Track Geometry
        8.2.1 Number of tracks
        8.2.2 Width of tracks
        8.2.3 Track location
        8.2.4 Track number
   8.3 Functional Testing
        8.3.1 Surface tests
        8.3.2 Track quality tests
        8.3.3 Rejection criterion
SECTION IV - RECORDING METHOD AND TRACK FORMAT
9 GENERAL REQUIREMENTS
   9.1 Mode of Recording
   9.2 Track Location Tolerance of the Recorded Flexible
        Disk Cartridge
   9.3 Recording Offset Angle
   9.4 Density of Recording
   9.5 Flux Transition Spacing
   9.6 Average Signal Amplitude
   9.7 Byte
   9.8 Sector
   9.9 Cylinder
   9.10 Cylinder Number
   9.11 Data Capacity of a Track
   9.12 Hexadecimal Notation
   9.13 Error Detection Characters (EDC)
10 TRACK LAYOUT
   10.1 Index Gap
   10.2 Sector Identifier
        10.2.1 Identifier Mark
        10.2.2 Address Identifier
   10.3 Identifier Gap
   10.4 Data Block
        10.4.1 Data Mark
        10.4.2 Data Field
        10.4.3 EDC
   10.5 Data Block Gap
   10.6 Track Gap
11 CODED REPRESENTATION OF DATA
   11.1 Byte coding
   11.2 Bit Coding
APPENDIX A - TEST FOR COMPLIANCE
APPENDIX B - MEASUREMENT OF LIGHT TRANSMITTANCE
APPENDIX C - METHOD FOR MEASURING THE EFFECTIVE TRACK WIDTH
APPENDIX D - PROCEDURE AND EQUIPMENT FOR MEASURING FLUX
             TRANSITION SPACING
APPENDIX E - DATA SEPARATORS FOR DECODING MFM RECORDING
APPENDIX F - EDC IMPLEMENTATION
APPENDIX G - CARTRIDGE DISTORTION TEST GAUGE
APPENDIX H - METHOD FOR MEASURING PEAK SHIFT
APPENDIX J - HEAD AND READ AMPLIFIER FOR FUNCTIONAL TESTING
APPENDIX K - PROCEDURE FOR DETERMINING TEST RECORDING CURRENT
             AND TEST ERASE CURRENT

Gives the characteristics of 90 mm flexible disk cartridges recorded at 31 831 ftprad using modified frequency modulation recording, on 80 tracks on each side. Such flexible disk cartridges are identified as ISO Type 303. Specifies the mechanical, physical and magnetic characteristics of the cartridge, so as to provide physical interchangeability between data processing systems. Also specifies the method of recording, the quality of the recorded signals, the track layout and the track format. Provides for full data interchange between data processing systems, together with ECMA-107.