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; {{{ Now, try to get the size of memory
E820H:
; NOTICE
; we assume that the maximum index of MRD structure is 128
; if the MRD entry count is bigger than 128, it can makes problem..
; but most system didn't uses more than 128.. I believe that...
; just believing...
; If this makes some problem. try fix it.
; and I will check this and tell it to the KERNEL, to handle it.. :)
        and BYTE [CPUTYPE], MEM_BIT_CLEAR
        or BYTE [CPUTYPE], E820_USED
        xor ebx, ebx
        mov [MRD_CNT], BYTE 0
        mov di, MRD
e_mem_info:
        mov eax, 0x0000E820     ; function
        mov edx, SMAP           ; signature
        mov ecx, 0x14           ; size of record

        push    ds
        pop     es                              ; set es to zero, di -> MemoryRangeDescriptor

        int 0x15                        ; interrupt
        jc E820H_error          ; no-carry = success

        cmp eax, SMAP
        jne E801H                       ; check signature

        cmp ecx, 0x14
        jne E801H                       ; check the size

        add di, 0x14            ; add 20 to DI

        cmp ebx, 0
        je mem_ok                       ; check EOF (ebx == 0)

        cmp BYTE [MRD_CNT], MRD_MAX_CNT
        jae E820H_over_cnt
        inc BYTE [MRD_CNT]

        jmp e_mem_info          ; LOOP

E820H_over_cnt:
        and BYTE [CPUTYPE], MEM_BIT_CLEAR
        or BYTE [CPUTYPE], E820_OVER
        jmp             mem_ok

E820H_error:
E801H:
        mov di, MRD
        and BYTE [CPUTYPE], MEM_BIT_CLEAR
        or BYTE [CPUTYPE], E801_USED
        stc
        xor     cx, cx
        xor     dx, dx
        mov ax, 0xe801
        int 0x15
        jc E801H_error

        cmp cx, 0
        jne E801_USE_CX_DX
        cmp dx, 0
        jne E801_USE_CX_DX
        mov ax, cx
        mov bx, dx

E801_USE_CX_DX:
        and edx, 0xffff
        shl edx, 6
        mov DWORD [di], edx
        and ecx, 0xffff
        add DWORD [di], ecx
        add di, 4
        jmp mem_ok

E801H_error:
E88H:           ; real value of function is '88h'
        mov di, MRD
        and BYTE [CPUTYPE], MEM_BIT_CLEAR
        or BYTE [CPUTYPE], E88_USED
        mov ah, 0x88
        int 0x15
        mov WORD [di], ax
        add di, 2
mem_ok:
        int 0x12
        mov WORD [di], ax
; }}}