Q.2 Media Formats
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## Q.2 Media Formats

The media format comprises two distinct components:

1. The Recording format, which addresses magnetic recording, track definition, sector headers, etc.

2. The Logical format, which addresses the organization of the data portion of sectors to support semantics of the file system.

### Q.2.1 Recording Format

The low level formatting shall be done using the GIGAMO standard. GIGAMO is published as a Sony-Fujitsu document and is currently not an ISO/IEC standard. The document specifying this formatting is the "GIGAMO 2.3GB 90mm Magneto-Optical Disk System in Cherry Book2 version 1.0". The Secondary Defect List shall be used.

### Q.2.2 Logical Format

The Logical Format for the 90mm 2.3GB disk shall be the PC File System ( Annex A).

The boot sector defined in Annex A shall have the following values.

Table Q.2-1. Boot Parameter Values for 90mm 2.3 GB Magneto-Optical Disk

Byte(s) | Value | Description
--- | --- | ---
11 - 12 | 0800H | 2048 Bytes/Sector
13 | 08H, 10H, 20H, or 40H | Sectors / cluster, either 8, 16, 32, or 64
21 | F8H | Flag for disk type F8H = Hard Disk
24-25 | 0019H (Nominal) | Nominally 25 sectors/track, but may vary, and any value should not affect interoperability
26-27 | 0001 (Nominal) | Nominally 1 head, but may vary, and any value should not affect interoperability.

### Note

When formatted the total formatted capacity of the disk is approximately 2.02GB.

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