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Combuster wrote:

DavidBG wrote:Here is a silly question but I have searched and searched for an answer:

Hmm, first hit on google for me: The manual. Includes fairly detailed instructions for a reference document.

Thanks, but I am not using VBE 3. I have already seen the 2 manual also. Bank Switching seems to hold the answer though.

I think that with all your help, I have quite a lot to go by, thanks all!

David

Have you considered using Unreal Mode? Even if you don't understand protected mode all you need is either a snippet of source code that sets it for you, or if you are working under DOS, a precompiled COM file that configures the processor into Unreal Mode. It's a very simple and basic thing to do. You can see here an unreal86.asm and an unreal86.com samples.

You could adapt it to your needs with some minor changes if you have some experience with assembly programming.

In that way, you could access the 32-bit address space from your Real Mode program, and thus could reach any address, in this case, the VESA video memory locations. You can use verions of x86 instructions (like MOV, a32 STOSD, a32 INSD, etc,) that are native to 32-bit protected mode from your 16-bit program.

I wonder why MS Virtual PC dosn't show SVGA printed text, while if I actually boot the OS, the BIOS does??? Must be a Useless OS bug. (That is my OS name)

I have a question: Can I use address 0xA000 to plot pixels in SVGA or not? That is all I want to know.

Thanks!
David

Forget it, I figured it all out.