32 lines
1.0 KiB
Markdown
32 lines
1.0 KiB
Markdown
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# Simple partition table format
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This document specifies a general partition table format suitable for both unmanaged disks, and tapes.
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## Partition table
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The partition table resides at the end of the disk - the last sector of the disk, for several reasons:
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- Ease of implementation for firmware to load from first partition
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- Compatibility with existing partition table formats
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The partition table takes one sector (512 bytes) and is divided into 16 entries, 32 bytes each.
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### Partition entry
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Each entry consists of:
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- A 20 byte name field, padded with null characters.
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- A 4 byte type field. This can be used either as a number or a string.
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- A 4-byte start sector field.
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- A 4-byte length field.
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Any entry with no name should be ignored.
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## Tape considerations
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It may prove easier to use a tape if one were to implement a virtual drive component that maps to the data on a tape.
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## Booting
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It is suggested that firmware loads and runs the first partition with type "boot". More advanced booting logic may be implemented if desired.
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