Boot loader signature. Strange.

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MarcoAlves

Joined: 09 Jun 2006
Posts: 30

MarcoAlves 20 Jun 2006, 13:10

Hi.

I'd read that the boot loader MUST have 512bytes long. Ok. That's is.
But, the 2 bytes at end must be AA and 55. When I see the first sector of
my hd with a disk editor, I note that it ends with 55 and AA.

The instruction as I learnt:

Code:

; End matter
times 510-($-$$) db 0 ; Boot loader MUST have 512 bytes long.
dw 0xAA55 ; Boot loader signature

But, when assembled, I opened with and hex editor, the ending appears
like the attached picture. Why?

Description:	My boot.asm assembled by FASM. Note that it ends with 55 AA.
Filesize:	210.47 KB
Viewed:	2112 Time(s)

20 Jun 2006, 13:10

LocoDelAssembly
Your code has a bug

Joined: 06 May 2005
Posts: 4624
Location: Argentina

LocoDelAssembly 20 Jun 2006, 14:25

What's wrong with that? I'ts at $1FE as expected and is 55 AA because of the little endian order.

20 Jun 2006, 14:25

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