mirror of
https://git.sr.ht/~asya/copycat
synced 2024-09-28 02:08:27 +00:00
28 lines
484 B
NASM
28 lines
484 B
NASM
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bits 16 ; we're in 16 bit real mode
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org 0xfe000 ; that's where we're loaded
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start: ; we jump here after the entry point
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mov ax, 0xFF
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push ax
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pop bx
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hlt
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; fill until the reset vector
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times 4080 - ($ - start) db 0
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; entry point
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; we shouldn't assume any initial state here
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cli
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; set up stack at 0:0x7c00
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; that's just below where we'll load the boot sector
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mov ax, 0
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mov ss, ax
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mov sp, 0x7c00
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; jump over to start
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jmp start
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; fill the last bytes
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times 4096 - ($ - start) db 0
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