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Carlos Fenollosa
2014-09-29 11:00:02 +02:00
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This is very exciting, we're going to create our own boot sector!
When the computer boots, the BIOS doesn't know how to load the OS, so it
delegates that task to the boot sector. Thus, the boot sector must be
placed in a known, standard location. That location is the first sector
of the disk (cylinder 0, head 0, sector 0) and it takes 512 bytes.
To make sure that the "disk is bootable", the BIOS checks that bytes
511 and 512 of the alleged boot sector are bytes `0xAA55`.
This is the simplest boot sector ever:
```asm
e9 fd ff 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 00 00 00 00 00 00 00 00 00 00 00 55 aa
```