RealMode Segmentation questions for Emulator

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Octocontrabass
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Re: RealMode Segmentation questions for Emulator

Post by Octocontrabass »

That's very strange that it would work with AL=0x13 but not AL=0x0D. Those are both real video modes, and all VGA-compatible graphics cards should support them both.
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Re: RealMode Segmentation questions for Emulator

Post by PearOs »

Octocontrabass wrote:That's very strange that it would work with AL=0x13 but not AL=0x0D. Those are both real video modes, and all VGA-compatible graphics cards should support them both.
That's what I thought. I'm going to start a new thread for making a V8086 task. Writing this Emulator has been fun and I've learned a lot but I don't want to spend the rest of my life implementing stuff until this thing is 100% flawless. I would rather use V8086 since it exists and move onto another part of my system. :) But thank you so much for your help, I really appreciate it.
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Re: RealMode Segmentation questions for Emulator

Post by Octocontrabass »

You're welcome. This was fun for me as well.

(Maybe I should write my own emulator now. :lol: )
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Re: RealMode Segmentation questions for Emulator

Post by PearOs »

Octocontrabass wrote:You're welcome. This was fun for me as well.

(Maybe I should write my own emulator now. :lol: )
Hahaha, it's a fun project. Very time consuming, and at times annoying but its cool to see the outcome. I just would rather use V86 and save some time plus it will run faster than my emulator ever could. :)
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Re: RealMode Segmentation questions for Emulator

Post by Combuster »

PearOs wrote:
Octocontrabass wrote:That's very strange that it would work with AL=0x13 but not AL=0x0D. Those are both real video modes, and all VGA-compatible graphics cards should support them both.
That's what I thought. I'm going to start a new thread for making a V8086 task. Writing this Emulator has been fun and I've learned a lot but I don't want to spend the rest of my life implementing stuff until this thing is 100% flawless. I would rather use V8086 since it exists and move onto another part of my system. :) But thank you so much for your help, I really appreciate it.
Mode 0x0D is weird, in the sense that it's inferior to both mode 0x12 and 0x13. Plus I don't recall a VGA register that does horizontal doubling (needed not to burn out monitors). Bottom line here is that I wouldn't be surprised if emulators neglected such support.

Also, using a legacy VGA mode number as a parameter to a VBE call is merely optionally supported.
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PearOs
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Re: RealMode Segmentation questions for Emulator

Post by PearOs »

Combuster wrote:
PearOs wrote:
Octocontrabass wrote:That's very strange that it would work with AL=0x13 but not AL=0x0D. Those are both real video modes, and all VGA-compatible graphics cards should support them both.
That's what I thought. I'm going to start a new thread for making a V8086 task. Writing this Emulator has been fun and I've learned a lot but I don't want to spend the rest of my life implementing stuff until this thing is 100% flawless. I would rather use V8086 since it exists and move onto another part of my system. :) But thank you so much for your help, I really appreciate it.
Mode 0x0D is weird, in the sense that it's inferior to both mode 0x12 and 0x13. Plus I don't recall a VGA register that does horizontal doubling (needed not to burn out monitors). Bottom line here is that I wouldn't be surprised if emulators neglected such support.

Also, using a legacy VGA mode number as a parameter to a VBE call is merely optionally supported.
Oh I see, thanks Combuster. I guess in gonna try v8086 task but it seems the emulator was actually a little easier :D

Thanks, Matt
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