ECMA 125 : 1ED 87

1 SCOPE, FIELD OF APPLICATION AND CONFORMANCE
   1.1 Scope and Field of Application
   1.2 Co nformance
2 REFERENCES
3 GENERAL DESCRIPTION
   3.1 Drawings
   3.2 Main Elements
   3.3 Description
4 DEFINITIONS
   4.1 Recording
   4.2 Hub
   4.3 Shutter
   4.4 Liner
   4.5 Case
   4.6 Master Standard Reference flexible Disk Cartridge
   4.7 Secondary Standard Reference Flexible Disk Cartridge
   4.8 Typical Field
   4.9 Reference Field
   4.10 Test Recording Current
   4.11 Standard Reference Amplitude
   4.12 Average Signal Amplitude
   4.13 In-Contact
   4.14 Side
   4.15 Direction of Rotation
   4.16 Index
   4.17 Line of Access
   4.18 Formatting
   4.19 Initialization
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. 1)
       6.1.2 Thickness
       6.1.3 Hub Access hole (Fig.1)
       6.1.4 Locating holes (Fig. 1 and 3)
       6.1.5 Label area
       6.1.6 Head windows (Fig.3)
       6.1.7 Write-inhibit hole (Fig.2)
       6.1.8 Identification hole (Fig. 1 and 2)
       6.1.9 Profile of the shutter edge of the case
             (Fig.1 and 3)
   6.2 Liner
   6.3 Disk
       6.3.1 Diameter
       6.3.2 Thickness
   6.4 Hub (Fig. 4)
       6.4.1 Dimensions
       6.4.2 Hub orientation holes (Fig.4)
   6.5 Optional Handling Notches (Fig. 1 and 2)
   6.6 Interface between cartridge and Drive
   6.7 Compliance
7 PHYSICAL CHARACTERISTICS
   7.1 Inflammability
   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
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
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 TRACT 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 Standards
   11.2 Coding Methods
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

Describes the characteristics of 90 mm flexible disk cartridges recorded at 15 916 ftprad using modified frequency modulation recording, on 80 tracks on each side - ISO Type 302. Also specifies the mechanical, physical and magnetic characteristics of the cartridge, so as to provide physical interchangeability between data processing systems.