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how to switch video modes (switching to VESA video modes too) in protected mode

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lukassevc:
Hi, I am Lukas,
and I am writing my operating system but I have problem with switching video modes ( switching to VESA modes too ) because I don't know how to do it and I don't found any tutorial on it so I need help. I know that in real mode it can by done by using ah = 0x00 and with interruption 0x10, but I am in protected mode so I don't know how to do it. Can someone help me please?
Thanks for any help!

fredericopissarra:
http://www.petesqbsite.com/sections/tutorials/tuts/vbe3.pdf

See "Obtaining the Protected Mode Entry Point", page 21 -- this is NOT available in all implementations and I was never been able to make it work properly...

lukassevc:

--- Quote from: fredericopissarra on May 16, 2019, 11:43:33 AM ---http://www.petesqbsite.com/sections/tutorials/tuts/vbe3.pdf

See "Obtaining the Protected Mode Entry Point", page 21 -- this is NOT available in all implementations and I was never been able to make it work properly...

--- End quote ---

I read it, and it seems to that it can work properly, but can you please tell me how to do it in C language?
Thanks!

fredericopissarra:

--- Quote from: lukassevc on May 16, 2019, 03:58:44 PM ---I read it, and it seems to that it can work properly, but can you please tell me how to do it in C language?
--- End quote ---
I could, but I thought this forum was about assembly language, isn't it?

ace012k8:
I ran into the same headache back when I was experimenting with writing a small OS kernel for fun. Switching to VESA modes in protected mode easily becomes a rabbit hole. I had to do a bunch of hacks just to get the BIOS to cooperate. The legacy BIOS interrupt (INT 0x10) just won't fly once you're out of real mode, so I remember relying on setting up a trampoline to call into real mode temporarily or using something like a VBE 2.0+ Linear Framebuffer approach after querying video modes beforehand.

For videos and demo recording, I always used a lightweight editor to polish up footage or build quick walkthroughs. If you’re working on dev-related content and want to make clean quick edits, especially on Windows, I picked up a solid one here: https://www.movavi.com/imovie-for-windows/. Easy to use and doesn’t overcomplicate things.

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