ECMA 207 : 1ED 94

Section 1 - General
1 Scope
2 Conformance
   2.1 Flexible disk cartridge
   2.2 Generating systems
   2.3 Receiving systems
3 References
4 Definitions
   4.1 Average Signal Amplitude
   4.2 case
   4.3 Data Sector
   4.4 Data Tracks
   4.5 direction of rotation
   4.6 disk
   4.7 Error Correcting Code (ECC)
   4.8 Error Detecting Code (EDC)
   4.9 flux transition frequency
   4.10 hub
   4.11 Index
   4.12 Inner Zone
   4.13 Input bit
   4.14 Line of Access of the head
   4.15 liner
   4.16 Master Standard Reference Flexible Disk Cartridge
   4.17 Outer Zone
   4.18 peak value
   4.19 Primary Identification hole
   4.20 Reference Field
   4.21 Secondary Identification hole
   4.22 Secondary Standard Reference Flexible Disk
        Cartridge
   4.23 Sector Block
   4.24 sector servo
   4.25 Servo Sector
   4.26 Servo Track
   4.27 shutter
   4.28 Side
   4.29 Standard Reference Amplitude
   4.30 Standard Reference Current
   4.31 Test Recording Current
   4.32 Typical Field
   4.33 write-inhibit hole
5 Conventions and Notations
   5.1 Representation of numbers
   5.2 Names
6 Acronyms
7 General description
   7.1 Drawings
   7.2 Main elements
   7.3 Description
   7.4 Marking of the FDC
Section 2 - Environments, mechanical and physical
            characteristics
8 General requirements
   8.1 Environment and transportation
        8.1.1 Testing environment
        8.1.2 Operating environment
        8.1.3 Storage environment
        8.1.4 Transportation
        8.1.5 Safety
   8.2 Materials
        8.2.1 Case
        8.2.2 Liner
        8.2.3 Disk
        8.2.4 Hub
9 Dimensional characteristics
   9.1 Case
        9.1.1 Shape
        9.1.2 Thickness
        9.1.3 Hub access hole
        9.1.4 Locating holes
        9.1.5 Label area
        9.1.6 Head windows
        9.1.7 Write-inhibit hole
        9.1.8 Identification holes
        9.1.9 Profile of the shutter edge of the case
        9.1.10 Shutter
   9.2 Liner
   9.3 Disk
        9.3.1 Diameter
        9.3.2 Thickness
   9.4 Hub
        9.4.1 Dimensions
        9.4.2 Hub orientation holes
   9.5 Optional handling notches
   9.6 Interface between cartridge and drive
   9.7 Compliance
10 Physical characteristics
   10.1 Flammability
   10.2 Coefficient of linear thermal expansion of the
        disk
   10.3 Coefficient of linear hygroscopic expansion of
        the disk
   10.4 Torque
        10.4.1 Starting torque
        10.4.2 Running torque
Section 3 - Requirements for the unrecorded disk
11 Magnetic characteristics
   11.1 Recording area
   11.2 Track geometry
        11.2.1 Number of tracks
        11.2.2 Track number
        11.2.3 Width of tracks
        11.2.4 Track location
   11.3 Functional testing
        11.3.1 Test conditions
        11.3.2 Typical Field
        11.3.3 Average Signal Amplitude
        11.3.4 Resolution
        11.3.5 Peak shift
        11.3.6 Overwrite
        11.3.7 Modulation
   11.4 Track quality tests
        11.4.1 Missing pulse
        11.4.2 Extra pulse
        11.4.3 Requirement for tracks
        11.4.4 Rejected cartridge
Section 4 - Requirements for the interchanged disk
12 Recording of Data Tracks
   12.1 Method of recording
   12.2 Tolerances of the track locations
   12.3 Recording offset angle
   12.4 Density of recording
         12.4.1 Nominal density of recording
         12.4.2 Long-term average Channel bit cell length
         12.4.3 Short-term average Channel bit cell length
   12.5 Flux transition spacing
   12.6 Average Signal Amplitude
   12.7 Byte
   12.8 Data Sector
   12.9 Cylinder
   12.10 Cylinder number
   12.11 Data capacity of a track
   12.12 Hexadecimal notation
13 Disk layout
   13.1 Layout of a Data Sector
         13.1.1 Compensation field
         13.1.2 Sector Identifier
         13.1.3 Identifier Gap
         13.1.4 Data Block
         13.1.5 Data Block Gap
         13.1.6 Defective Data Sector
   13.2 Data Tracks
         13.2.1 Data Tracks for user
         13.2.2 Data Tracks for the management of defective
                 Data Sectors
         13.2.3 Data Tracks for servo recovery
   13.3 Coded representation of data
14 General requirements for recording Servo Tracks
   14.1 Method of recording
   14.2 Servo Tracks
         14.2.1 Number of Servo Tracks
         14.2.2 Width of Servo Tracks
         14.2.3 Servo Track location
   14.3 Average Signal Amplitude of servo data
   14.4 Displacement due to fluctuations of signal amplitude
         of servo data
15 Layout of the Servo Track
   15.1 Layout of the Servo Sector
         15.1.1 Servo Identifier
         15.1.2 Servo data
16 Relative position of Data Tracks and Servo Tracks
Annexes
A - Cartridge distortion test gauge
B - Measurement of light transmittance
C - Test for compliance
D - Method for measuring the effective track width
E - Head and read amplifier for functional testing
F - Method of measuring peak shift
G - Method for measuring overwrite
H - Procedure and equipment for measuring flux transition
    spacing
J - The disposal of the defective Data Sector
K - Method for measuring the eccentricity of Servo Tracks
L - Method of measuring the offset between Data Tracks
    and Servo Tracks
M - Torque measurements
N - Data separators for decoding 2-7 RLL recording
P - EDC Implementation
Q - ECC Implementation
R - Servo Track recording conditions
S - Method for measuring the displacement of the head due
    to amplitude fluctuations of servo data
T - Institute supplying Secondary Reference Flexible Disk
    Cartridges

Specifies the characteristics of 90 mm flexible disk cartridges (FDC) of 21 Mbytes formatted capacity, recorded at 31 831 ftprad in the Inner Zone and 47 747 ftprad in the Outer Zone with sector servo tracking on 326 data tracks on each side, using 2-7 RLL recording. Also 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 recorded signals, the track layouts and the track formats of data tracks and servo tracks.