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Date:	Tue, 01 Nov 2005 23:35:11 +0100
From:	Pafo007 <"Pafo007 at wanadoo dot fr"@unknown.addr>
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Subject:	Re: Why the call instruction points 2 bytes before to the real start
	sub-routine ?
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Ouch! Going to 32bits mode isn't a easy thing: you have to build a GDT, 
to load GDTR with LGDT intruction, to set bit0 of CR0 register and to 
jump to your code in a 32bits segment... That's a hard way if you 
haven't read anything about it!
Perhaps should you try this:
http://www.osdever.net/tutorials/pmodetuts/all_pm_tuts.zip?the_id=36
That's a 17 chapter book about protected mode...


Diego Cueva a écrit :
> Thanks for your response.
> 
> Now I am using a 32 bit disassembler:
> 
> 00000000  90                nop
> 00000001  E80B000000        call 0x11
> 00000006  66BE5C01          mov si,0x15c
> 0000000A  E834000000        call 0x43
> 0000000F  CD20              int 0x20
> 00000011  6650              push ax
> 00000013  6653              push bx
> 00000015  6651              push cx
> 00000017  6652              push dx
> 00000019  B406              mov ah,0x6
> 0000001B  B000              mov al,0x0
> 0000001D  B500              mov ch,0x0
> 
> This dis-assembled code is correct, but when I run the program does not
> work fine. 
> 
> The program act as a 16 bit code, this mean that the 1st CALL
> instruction, jump to 010F. In other words, this compiled program only
> execute:
>     100. - NOP
>     101. - CALL    010F (jump really to 10F not to 0x11)
>     10F. - INT 0x20   :(   That's all.

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