I.S. EN ISO/IEC 9661:1998

Section 1 - General
1 Scope
2 Conformance
3 Normative references
4 Definitions
    4.1 Average signal amplitude
    4.2 Back surface
    4.3 Beginning of Tape (BOT)
    4.4 Byte
    4.5 Cartridge
    4.6 Cyclic Redundancy Check character
    4.7 Data density
    4.8 Error Correcting Code
    4.9 Flux transition position
    4.10 Flux transition spacing
    4.11 Magnetic tape
    4.12 Master Standard Reference Tape
    4.13 Physical recording density
    4.14 Postamble
    4.15 Preamble
    4.16 Reference field
    4.17 Secondary Standard Reference Tape
    4.18 Standard reference amplitude
    4.19 Standard reference current
    4.20 Test recording current
    4.21 Track
    4.22 Typical field
5 Environment and safety
    5.1 Cartridge/Tape testing environment
    5.2 Cartridge operation environment
    5.3 Cartridge storage environment
    5.4 Safety requirements
    5.5 Transportation
Section 2 - Tape requirements
6 Characteristics of the tape
    6.1 Material
    6.2 Tape length
    6.3 Tape width
    6.4 Tape discontinuity
    6.5 Total thickness of tape
    6.6 Base material thickness
    6.7 Longitudinal curvature
    6.8 Out-of-plane distortions
    6.9 Cupping
    6.10 Dynamic frictional characteristics
    6.11 Coating adhesion
    6.12 Flexural rigidity
    6.13 Electrical resistance of coated surfaces
    6.14 Tape durability
    6.15 Inhibitor tape
    6.16 Tape abrasivity
    6.17 Pre-recording condition
    6.18 Magnetic recording characteristics
    6.19 Tape quality
7 Dimensional and mechanical characteristics of the
    cartridge
    7.1 Overall dimensions
    7.2 Write-inhibit mechanism
    7.3 Label area of the rear side
    7.4 Label area of the top side
    7.5 Case opening
    7.6 Locating notices
    7.7 Locating areas
    7.8 Inside configuration of the case around the
          case opening
    7.9 Other external dimensions of the case (figure 8)
    7.10 Central window
    7.11 Stacking ribs
    7.12 Flexibility of the case
    7.13 Tape reel
    7.14 Leader block
    7.15 Attachment of the tape to the leader block
    7.16 Latching mechanism
    7.17 Tape wind
    7.18 Wind tension
    7.19 Circumference of the tape reel
    7.20 Moment of inertia
Section 4 - Recording requirements
8 Method of recording
    8.1 Physical recording density
    8.2 Bit cell length
    8.3 Average bit cell length
    8.4 Long-term average bit cell length
    8.5 Short-term average bit cell length
    8.6 Rate of change
    8.7 Bit shift
    8.8 Total character skew
    8.9 Read signal amplitude
    8.10 Coincident missing pulses
9 Track format
    9.1 Number of tracks
    9.2 Reference edge
    9.3 Track positions
    9.4 Track width
    9.5 Azimuth
10 Data format
    10.1 Types of bytes
    10.2 Frame
    10.3 Data Block
    10.4 Error Correcting Code (ECC)
    10.5 Recording of 8-bit bytes on the tape
    10.6 Recorded Data Block
    10.7 Data density
11 Tape format
    11.1 Density Identification Burst
    11.2 ID Separator Burst
    11.3 Interblock Gaps
    11.4 Erase Gaps
    11.5 Tape Marks
    11.6 Relationship between Interblock Gaps, Erase
          Gaps and Tape Marks
    11.7 First and last recording on the tape
    11.8 Summary of the tape format
Annexes
A Recommendations for transportation
B Inhibitor tape
C Tape abrasivity measurement procedure
D Recommendations on tape durability
E Pre-recording condition
F Representation of 8-bit bytes by 9-bit patterns
G Measurement of bit shift
H Dimensions of the cartridge

Defines the physical and magnetic characteristics of a 12,7 mm, 18-track magnetic tape cartridge to allow interchangeability of such cartridges. It also defines the quality of the recorded signals, together with the format and recording method, therefore allowing full data interchange using magnetic tape cartridges.