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; Here is the disk_packet struct...
align 4
	disk_packet    db 10h									; 10h or 18h Disk Packet Structure for Extended int 13h loads(size).
			       db 0										; reserved.
			       db 32									; block count to transfer (max 07fh for phoenix edd).
			       db 0										; reserved
			       dw 0,0									; ofs:seg for read/write buffer (if ffffh:ffffh use last qword and 18h).
			       dq 1										; qword block start (2nd sector).
			       dq 0										; Float 64bit address of transfer buffer if dword at 4 is ffff:ffff (EDD3). (not used).

; here is the code snippet.. load... the val in EAX and CL and ES:BX I've checked and they're correct.. 
; ONE thing i did notice in the spec doc there is 1 byte for the sector count and a reserved byte, in RB's int list there is a a full DW (word)?!?

	mov esi,offset disk_packet
	mov dword ptr ds:[esi+12],0
	mov dword ptr ds:[esi+8],eax	; Store Starting Sector.
	mov byte ptr ds:[esi+2],cl		; Store Sector Count to disk_packet.
	mov ax,es
    mov word ptr ds:[esi+6],ax		; Store Segment to Load To.
    mov eax,ebx
    mov word ptr ds:[esi+4],ax		; Store Offset to Load To.
    mov dl,fs:[BOOT_DRIVE_ID]
	mov ax,4200h
	int 13h