29 lines
975 B
NASM
29 lines
975 B
NASM
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;=----------------------------------------------------------------------------=;
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; GNU GPL OS/K ;
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; ;
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; Authors: spectral` ;
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; NeoX ;
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; ;
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; Desc: Basic Memory Long mode Functions ;
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; (x86_64 architecture only) ;
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;=----------------------------------------------------------------------------=;
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[BITS 64]
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;; GLOBAL DATA
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A20_OK db 0
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;; TEXT
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check_a20:
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cmp BYTE [A20_OK], 1
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je .A20Success
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mov bl, 0x0C
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mov esi, Fail
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call write
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jmp Die
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.A20Success:
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mov bl, 0x0A
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mov esi, Pass
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call write
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ret
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