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Add documentation for bootloader memory structure

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Robbe Van Herck 2020-01-03 13:02:49 +01:00
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docs/bootloader.md
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@ -14,6 +14,19 @@
| 0x80000 | 0x9ffff | EDBA, partially usable |
| 0xa0000 | 0xfffff | unusable |
## Bootsector layout
(all addresses are offsets from 0x7C00)
| start | end | use |
|--------|--------|-------------------|
| 0x0000 | ? | Bootloader code |
| ? | 0x0193 | _padding_ |
| 0x0194 | 0x01bd | SFS header |
| 0x01be | ? | _padding_ |
| ? | 0x01fd | data |
| 0x01fe | 0x01ff | 0x55AA boot magic |
## Drive layout
The first 512 bytes are the bootloader, right after that the 32-bit kernel ELF-file, this kernel can be 32KiB big. In the future, this "kernel" can be replaced by a second stage of the bootloader.