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-   -   protected mode programming guide (http://www.daniweb.com/forums/thread96274.html)

sgk26p10p07 Nov 11th, 2007 8:34 am
protected mode programming guide
 
Anyone to help with protected mode programming,like help me create a a data descriptor pointing to 0b800h when i try to write to RAM it rebbots

Ancient Dragon Nov 11th, 2007 8:40 am
Re: protected mode programming guide
 
Protected mode does not have access to real mode addresses. You have to switch back to real mode to access it. Yes its a pain in the butt. How to do it? I don't know, all I know is what I've read from documentation of dos extenders such as Phar Lap. Unfortunately when MS-DOS died so did many other companies such as Phar Lap.

sgk26p10p07 Jan 8th, 2008 5:44 am
Re: protected mode programming guide
 
heya why is it that wen i switch back to real mode i cant access real mode interrupts even when i never modified anythang like for instance this code
mov EAX,CR0
OR AL,0H
MOV CR0,EAX;THEN SWITCH BACK TO REAL MODE
MOV EAX,CR0
AND AL,10B
MOV CR0,EAX
;THEN INT 10H
MOV AX,3H
INT 10H
;THEN MY PROGRAM DOESNT RESPOND PLS HEL-P

sgk26p10p07 Jan 8th, 2008 5:46 am
Re: protected mode programming guide
 
Oh, No The
Or Al,1h ;not 0h Sorry


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