84 lines
1.2 KiB
NASM
84 lines
1.2 KiB
NASM
[BITS 16]
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real_hexprint:
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xor cx, cx
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mov bl, al
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shr al, 4
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jmp .donibble
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.nibble2:
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mov al, bl
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inc cx
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.donibble:
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and al, 0x0F
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cmp al, 0x0A
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jl .noadjust
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add al, 'A' - '0' - 10
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.noadjust:
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add al, '0'
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mov ah, 0x1f
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stosw
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test cx, cx
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jz .nibble2
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ret
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real_printword:
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mov dx, ax
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mov al, ah
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call real_hexprint
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mov ax, dx
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call real_hexprint
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ret
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extern v86Code
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v86Code:
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mov ax, 0xb814
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mov es, ax
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mov di, 20
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mov ax, sp
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call real_printword
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add di, 2
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mov ax, ds
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call real_printword
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add di, 2
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mov ax, cs
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call real_printword
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.loop:
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inc byte [0]
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;mov ax, 0x1111
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;mov ds, ax
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;mov ax, 0x2222
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;mov es, ax
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;mov ax, 0x3333
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;mov fs, ax
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;mov ax, 0x4444
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;mov gs, ax
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;mov ax, 0x5555
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;mov ss, ax
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;mov ax, 0x6666
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;mov sp, ax
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int 3
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int 3
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;jmp .loop
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mov ax, 0x13
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int 0x10
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int 0x30 ; exit
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jmp $
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extern real_test
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real_test:
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nop
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nop
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nop
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jmp $
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[BITS 32]
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; extern void enter_v86(uint32_t ss, uint32_t esp, uint32_t cs, uint32_t eip);
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global enter_v86
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enter_v86:
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mov ebp, esp ; save stack pointer
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mov dword [0x20004], ebp ; tss ESP0
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push dword [ebp+4] ; ss
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push dword [ebp+8] ; esp
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pushfd ; eflags
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or dword [esp], (1 << 17) ; set VM flags
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;or dword [esp], (3 << 12) ; IOPL 3
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push dword [ebp+12] ; cs
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push dword [ebp+16] ; eip
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iret
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