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Hi
How do I change screen modes without using DOS or BIOS calls, so going to the hardware it's self. Also what about this 50 line mode, is that just a DOS hack, or can I implement it myself?

Thanks

There must be some way of doing it!! All examples I've found use BIOS.

You can, you must use directly the ports of the VGA(or any other card). The problem is that you must do a lot of things. The easy way is using BIOS, but if you wants to do it in pmode, i think the VESA 2.0+ have pmode functions u can use.

About the 50 lines mode is not a DOS hack, they do it changing the VGA registers(trought the ports, of course)

I think I shall come back to that at a later date, as I don't plan to use VESA yet, just VGA.

BTW Do you know of any places where I can find out exactly what I need to do, using the ports, to change video mode. I can then go back to that as a reference. Or, I do have the source of the linux kernel 2.4, where would it be in that?

Thanks

I think this has been answered on this forum, possibly even by me. Do a search and see where it takes you. In VGA, it's fairly simple to do once you understand how the video registers work.

found it

What is that initalised data all for?

without a reference, I can't be 100% sure of what you mean, but I think you're talking about the values which are fed to ports. There is a good explanation of the ports somewhere. I'll see if I can dig it up as soon as I get a chance.

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