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mov   byte [fs:0xB809E], "1"  ;print 1
NoKey1:
xor   eax,eax      
in    al,60h         ; get key press
cmp   al,0x1c      ; check if enter
jne   NoKey1       ; if not loop

; SOME TEST CODE HERE

mov   byte [fs:0xB809E], "2"
NoKey2:
xor   eax,eax 
in    al,60h
cmp   al,0x1c   
jne   NoKey2 

; SOME TEST CODE HERE

mov   byte [fs:0xB809E], "3"
NoKey3:
xor   eax,eax 
in    al,60h
cmp   al,0x1c   
jne   NoKey3 

; SOME TEST CODE HERE

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    xor eax, eax      ; calcule l'adresse lineaire de GDT -- EAX IS 0 NOW
    xor ebx, ebx
    mov ax, ds               ; WHY DO YOU WANT THE VALUE OF DS
    mov ecx, eax
    shl ecx, 4
    mov bx, gdt          ; THE LABEL gdt IS 32 BITS IN SIZE. ONLY MUST DO MOV EBX,gdt 
    add ecx, ebx        ; ADDING THE WRONG VALUE
    mov dword [gdtptr+2], ecx

; passage en modep 
    cli                       
    lgdt [gdtptr]    ; charge la gdt
    mov eax, cr0                               
    or  ax, 1
    mov cr0, eax        ; PE mis a 1 (CR0) ; DS MUST BE ZERO BEFORE JUMPING TO PROTECTED MODE 

    jmp 0x8:next

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; YOU HAVENT CHANGED YOUR CS  SO IT IS GARBAGE AT BOOT TIME. EITHER THAT OR ORG 7C00
[ORG 0x0] 

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[BITS 16]
mov ax , Label1 ; Here Label1 is a 16 bit address
Label1:
    .....some-code.....

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[BITS 32]
mov ax , Label1 ; Here Label1 is a 32 bit address
Label1:
    .....some-code.....

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[BITS 16]
mov ax , Label1 ; Here Label1 is a 32 bit address. SO THIS WILL RESULT IN THE LOWER 16 BITS OF THE
                        ; ADDESS OF LABEL1 being entered into ax
mov eax, Label1 ; Here you get what is expected
[BITS 32]
Label1:
    .....some-code.....

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[BITS 32]
mov ax , Label1 ; Here Label1 is a 16 bit address. SO THIS WILL RESULT IN THE LOWER 16 BITS OF THE
                        ; ADDESS OF LABEL1 being entered into ax. THIS IS AS EXPECTED
mov eax, Label1 ; Here you get what is NOT expected. The higher EAX is now garbage
[BITS 16]
Label1:
    .....some-code.....

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mov dword [gdtptr+2], ecx ; which gets the 16 bit address of gdtptr and adds 2 which is not what you want

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[BITS 16]
[ORG 0x7C00]

jmp 0:start

start:

    cli
	mov ax , 0 
	mov ds , ax  ;################ SET DS TO 0

    lgdt [GDTR]    ; charge la gdt
    mov eax, cr0
    or  ax, 1
    mov cr0, eax        ; PE mis a 1 (CR0)


    jmp dword 8:protected
    
    
[BITS 32]

protected:

    mov ax, 0x10        ; segment de donne
    mov ds, ax
    mov fs, ax
    mov gs, ax
    mov es, ax
    mov ss, ax
    mov esp, 0x9F000   

	 jmp $  ;   if I do that I see my boot message


    jmp 0x8:0x1000    ; It restart my real computer & works in VMs



GDTR :
		dw	GDT_End - GDT - 1			;	16 Bit Size Limit Of GDT
		dd	GDT						;	32 Bit Linear Address Of GDT

GDT :
		dd	0x00000000 ,   0x00000000		;	Null
		dd	0x0000FFFF ,   0x00CF9A00		;	Kernel Code
		dd	0x0000FFFF ,   0x00CF9200		;	Kernel Data
		dd	0x0000FFFF ,   0x00CFFA00		;	User Code
		dd	0x0000FFFF ,   0x00CFF200		;	User Data
GDT_End :


times 510-($-$$) db 144
dw 0xAA55

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Mov cr0, eax
jmp 8:next
[BITS 32]
next:
; some code which init segments
mov byte [0xb8a00], 'H'
mov byte [0xb8a01], 0x57

jmp 0x1000