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4. Segment Start, Limit, and Status

  • A typical segment descriptor contains the following information, packed into an 8-byte record:

    • Segment start: absolute 32-bit address of segment controlled by this descriptor

    • Segment limit: 20-bit field containing maximum address this segment can reference

    • Segment status: privilege level, segment present, segment available, segment type, etc.

  • Segment selector -> Segment descriptor -> Memory

      Protected Mode Architecture

      A segment descriptor

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