How do you draw a background for the screen?

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Redragon

Joined: 27 Nov 2004
Posts: 101
Location: U.S.

Redragon

This code sets the screen res to 640x480 and displays the bg color below.. Ive already got into protected mode and everything work but i think the problem is in this code..when it show up on the screen, it shows the color correctly, but it dosent make it full screen, it leaves a small black gap at the bottom..if i go into 1024x768 it leaves a black gap in the middle, im not sure whats wrong with it..thanks for the help!

Code:

mov   eax,00009999h 
               mov   ecx,480*640     
               mov   edi,[vesa_str]  ;defined in vesa file
               rep   stosd

17 Feb 2005, 03:42

Dex4u

Joined: 08 Feb 2005
Posts: 1601
Location: web

Dex4u

Code:

mov   eax,00009999h mov   ecx,480*640     mov   edi,[vesa_str]   clirep  stosdsti

Does that make a difference ?.

17 Feb 2005, 17:00

Redragon

Joined: 27 Nov 2004
Posts: 101
Location: U.S.

Redragon

when i use that it dosent even show the screen, it attempts to, then the computer restarts.. its not an interupt problem

17 Feb 2005, 22:45

Dex4u

Joined: 08 Feb 2005
Posts: 1601
Location: web

Dex4u

So you have not set your 'IDT' up yet, and you have disabled interrupts ? .
I got a similar black gap at the bottom of screen in CdPod (which is 640x480), i covered it up with a fade, this was because i did not enable A20, maybe theres where your problem lies.

18 Feb 2005, 02:38

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