# 80×86 Architecture: Windows Virtual Device Driver

Assembler code

```
ICOD:C001A45F
ICOD:C001A45F loc_C001A45F:                           ; CODE XREF: Locate_Byte_In_ROM+D↑j
ICOD:C001A45F                 xor     esi, esi
ICOD:C001A461                 mov     edi, offset aSystemrombreak ; "SystemRomBreakPoint"
ICOD:C001A466                 VMMCall Get_Profile_Boolean
ICOD:C001A46C                 test    eax, eax
ICOD:C001A46E                 jz      short loc_C001A495
ICOD:C001A470                 mov     al, 73h ; 's'
ICOD:C001A472                 VMMCall Get_Debug_Options
ICOD:C001A478                 jz      short loc_C001A495
ICOD:C001A47A                 mov     edi, 0FFFEFh
ICOD:C001A47F                 mov     ecx, 3FF0h
ICOD:C001A484                 mov     eax, [esp+20h+var_4]
ICOD:C001A488                 std
ICOD:C001A489                 repne scasb
ICOD:C001A48B                 jnz     short loc_C001A495
ICOD:C001A48D                 inc     edi
ICOD:C001A48E                 mov     [esp+20h+var_4], edi
ICOD:C001A492                 clc
ICOD:C001A493                 jmp     short loc_C001A496
ICOD:C001A495 ; ---------------------------------------------------------------------------
ICOD:C001A495
ICOD:C001A495 loc_C001A495:                           ; CODE XREF: Locate_Byte_In_ROM+23↑j
ICOD:C001A495                                         ; Locate_Byte_In_ROM+2D↑j ...
ICOD:C001A495                 stc
ICOD:C001A496
ICOD:C001A496 loc_C001A496:                           ; CODE XREF: Locate_Byte_In_ROM+48↑j
ICOD:C001A496                 cld
ICOD:C001A497                 popa
ICOD:C001A498                 retn
ICOD:C001A498 Locate_Byte_In_ROM endp
ICOD:C001A498
ICOD:C001A499 ; ---------------------------------------------------------------------------
ICOD:C001A499
ICOD:C001A499 loc_C001A499:                           ; CODE XREF: start+756↓p
ICOD:C001A499                 push    ebx

```


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