Refactored into multiple files

v86.nasm

@@ -0,0 +1,81 @@
+[BITS 16]
+real_hexprint:
+xor cx, cx
+mov bl, al
+shr al, 4
+jmp .donibble
+.nibble2:
+mov al, bl
+inc cx
+.donibble:
+and al, 0x0F
+cmp al, 0x0A
+jl .noadjust
+add al, 'A' - '0' - 10
+.noadjust:
+add al, '0'
+mov ah, 0x1f
+stosw
+test cx, cx
+jz .nibble2
+ret
+real_printword:
+mov dx, ax
+mov al, ah
+call real_hexprint
+mov ax, dx
+call real_hexprint
+ret
+extern v86Code
+v86Code:
+mov ax, 0xb814
+mov es, ax
+mov di, 20
+mov ax, sp
+call real_printword
+add di, 2
+mov ax, ds
+call real_printword
+add di, 2
+mov ax, cs
+call real_printword
+.loop:
+inc byte [0]
+;mov ax, 0x1111
+;mov ds, ax
+;mov ax, 0x2222
+;mov es, ax
+;mov ax, 0x3333
+;mov fs, ax
+;mov ax, 0x4444
+;mov gs, ax
+;mov ax, 0x5555
+;mov ss, ax
+;mov ax, 0x6666
+;mov sp, ax
+int 3
+;jmp .loop
+mov ax, 0x13
+int 0x10
+int 0x30 ; exit
+jmp $
+extern real_test
+real_test:
+nop
+nop
+nop
+jmp $
+[BITS 32]
+; extern void enter_v86(uint32_t ss, uint32_t esp, uint32_t cs, uint32_t eip);
+global enter_v86
+enter_v86:
+mov ebp, esp               ; save stack pointer
+push dword  [ebp+4]        ; ss
+push dword  [ebp+8]        ; esp
+pushfd                     ; eflags
+or dword [esp], (1 << 17)  ; set VM flags
+;or dword [esp], (3 << 12) ; IOPL 3
+push dword [ebp+12]        ; cs
+push dword  [ebp+16]       ; eip
+iret
+