38 lines
585 B
NASM
38 lines
585 B
NASM
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mov ah, 0x0e ; tty mode
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mov bp, 0x8000 ; far away from 0x7c00, want to avoid overwriting ourself
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mov sp, bp ; if stack empty, sp points to bp
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push 'A'
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push 'B'
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push 'C'
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; stack grows downwards
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mov al, [0x7ffe] ; 0x8000 - 2
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int 0x10
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; you can only access stack top now
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mov al, [0x8000]
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int 0x10
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; recover chars with pop
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; you can onoly pop words, so you need an aux register to manipulate the lower byte
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pop bx
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mov al, bl
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int 0x10
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pop bx
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mov al, bl
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int 0x10
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pop bx
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mov al, bl
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int 0x10
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; pop'd stack is garbage now
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mov al, [0x8000]
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int 0x10
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jmp $
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times 510-($-$$) db 0
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dw 0xaa55
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