Odd video modes

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jal
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Re: Odd video modes

Post by jal »

Troy Martin wrote:You can also get 80x30 in real mode fairly easy by activating 640x480 graphics mode and adding a "mov bl,07h" statement before every usage of int 10h ah=0Eh. Haven't tried activating 8x8 in graphics mode though!
Using graphics mode for text would kinda defeat the purpose. Terribly slow.


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Troy Martin
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Re: Odd video modes

Post by Troy Martin »

The text mode cursor gets disabled as well so you'd need to use an underscore or some other character to show the cursor.

Oh, and don't try doing 80x60, it does weird things with the graphics in Virtual PC and Bochs, so I'm guessing it's possible it could damage a CRT monitor.
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I wish I could add more tex
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Love4Boobies
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Re: Odd video modes

Post by Love4Boobies »

About weird things; did anyone else notice that QEMU behaves horribly in fullscreen under text modes?
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Re: Odd video modes

Post by Owen »

Modern CRTs are pretty bomb proof. Modern desktop LCDs are safe, as they have integral scalers rather than running directly off the display clock.

But laptop LCDs are very easy to destroy, as many an X.Org developer has learnt the hard way
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Re: Odd video modes

Post by Love4Boobies »

That's not what I meant. Besides, QEMU can cause no harm; it uses the OS host OS' services to draw to the screen, it doesn't have access to I/O ports, etc. What I meant was that the screen doesn't get updated properly and it looks funny.
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Troy Martin
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Re: Odd video modes

Post by Troy Martin »

When I said "damage a CRT monitor" I meant on RHW only, not virtualized, just RHW. And probably on an older monitor too.
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Solar wrote:It keeps stunning me how friendly we - as a community - are towards people who start programming "their first OS" who don't even have a solid understanding of pointers, their compiler, or how a OS is structured.
I wish I could add more tex
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Love4Boobies
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Re: Odd video modes

Post by Love4Boobies »

Sorry, I didn't read your post. I thought Owen was referring to mine about QEMU behaving badly. :oops:
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