GetBestGraficMode

[BITS 16]
mov bx, 0x7E00
mov es, bx
mov di, 0
mov [es:di], dword "VBE2"
mov ax, 0x4F00
int 0x10
mov bx, 0x7E00
mov es, bx
mov di, 4
mov ax, [es:di]
cmp ax, 0x300
je VBE_3
cmp ax, 0x200
je VBE_2
jmp VBE_1
jmp kernelerror
VBE_3:
    jmp VBE_2
VBE_2:
    mov word [Grafic_Mode_number-start], 0
    Choose_Best_Grafic_Mode:
        call Get_Grafic_Mode_Info
        cmp word [Grafic_Mode_number-start], 1024
        je Set_Best_Grafic_Mode
        ; ...
        mov bx, 0x8000
        mov es, bx
        mov di, 0
        mov ax, [es:di]
        and ax, 10000000b
        cmp ax, 0
        je Next_Mode
        ; ...
        mov bx, 0x8000
        mov es, bx
        mov di, 0
        mov ax, [es:di]
        and ax, 00010000b
        cmp ax, 0
        je Next_Mode
        ; ...
        mov bx, 0x8000
        mov es, bx
        mov di, 27
        mov al, [es:di]
        cmp al, 0x6
        jne Next_Mode
        mov bx, 0x8000
        mov es, bx
        mov di, 18
        mov ax, [es:di]
        cmp ax, word [Best_XResolution-start]
        jg Better_Grafic_Mode_Found
        je Best_XResolution_Equal
        Next_Mode:
            inc word [Grafic_Mode_number-start]
            jmp Choose_Best_Grafic_Mode
    Best_XResolution_Equal:
        mov bx, 0x8000
        mov es, bx
        mov di, 20
        mov ax, [es:di]
        cmp ax, word [Best_YResolution-start]
        jg Better_Grafic_Mode_Found
        je Best_YResolution_Equal
        jmp Next_Mode
    Best_YResolution_Equal:
        mov bx, 0x8000
        mov es, bx
        mov di, 25
        mov al, [es:di]
        cmp al, byte [Best_BitsPerPixel-start]
        jg Better_Grafic_Mode_Found
        jmp Next_Mode
    Better_Grafic_Mode_Found:
        mov bx, 0x8000
        mov es, bx
        mov di, 18
        mov ax, [es:di]
        mov word [Best_XResolution-start], ax
        mov bx, 0x8000
        mov es, bx
        mov di, 20
        mov ax, [es:di]
        mov word [Best_YResolution-start], ax
        mov bx, 0x8000
        mov es, bx
        mov di, 25
        mov al, [es:di]
        mov byte [Best_BitsPerPixel-start], al
        mov ax, word [Grafic_Mode_number-start]
        mov word [Best_Mode-start], ax
        jmp Next_Mode
    Get_Grafic_Mode_Info:
        mov bx, 0x7E00
        mov es, bx
        mov di, 14
        mov si, [es:di]
        mov es, [si]
        mov ax, word [Grafic_Mode_number-start]
        mov di, ax
        mov cx, [es:di]
        mov bx, 0x8000
        mov es, bx
        mov di, 0
        mov ax, 0x4F01
        int 0x10
        ret
    Set_Best_Grafic_Mode:
        mov bx, 0x7E00
        mov es, bx
        mov di, 14
        mov si, [es:di]
        mov es, [si]
        mov di, word [Best_Mode-start]
        mov cx, [es:di]
        and cx, 0111111111111111b
        mov bx, 0x8000
        mov es, bx
        mov di, 0
        mov ax, 0x4F01
        int 0x10
        mov bx, 0x7E00
        mov es, bx
        mov di, 14
        mov si, [es:di]
        mov es, [si]
        mov di, word [Best_Mode-start]
        mov bx, [es:di]
        and bx, 0111111111111111b
        mov ax, 0x4F02
        int 0x10
        jmp GraficModeSet
VBE_1:
    mov cx, 0x115
    mov bx, 0x8000
    mov es, bx
    mov di, 0
    mov ax, 0x4F01
    int 0x10
    mov bx, 0x115
    mov ax, 0x4F02
    int 0x10
jmp GraficModeSet