Choice of Correct Resolution Old DOS Games

Fricco81
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Choice of Correct Resolution Old DOS Games

Unread post by Fricco81 »

Hi Guys I've a question for You

I'm thinking of buying MiSTer FPGA in order to play My favorite Old DOS Games and Some Amiga Games
I've a Sony G220 multiscan with VGA input
The Horizontal Scan rate Is 31khz and Up (I Can't Get 15khz)
I'd connect My monitor CRT Via VGA cable with MISTer analogue output
The 80% of the DOS games I'm into are 320*200 resolution
Does Aos 4086 Core allow me to play games in the native 320*200 or Only at 640*480?
Another problem Is that MISTer Only gives you 15khz and My Sony Is Only 31 and Up.
I'm forced to use scandoubler Is right? The image Will be Upscaled? Is It bad?
Thanks to All
FoxbatStargazer
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Re: Choice of Correct Resolution Old DOS Games

Unread post by FoxbatStargazer »

AO486 core doesn't have a "real" analog output, so you have to set a resolution and appropriate scaling parameters, as if it was an HDMI display. You can use direct video and forced scandoubler to get something going, but that is just more like a default resolution (640x480), you get more control by picking your own resolution.

For the most "authentic" look on a VGA CRT monitor, you will want to output 400p @70hz. 640x400 will look fine for games, but DOS text is 720 wide so might look a little blurred. Personally I use 1600x400, with HV integer scale, wide/full aspect ratio, "no interpolation" filter. This makes 320x200 games look perfect, and DOS text is slightly squished/tall with small pillarbox on sides but all pixels are 1:1 accurate. It takes some tinkering but you can get DOS to look great on a VGA CRT. You need completely different settings if you want to run windows or 480p games though, which can be a hassle.

There is also some fork that switches actual resolution between 720x400 and 640x400 for the most authentic/cleanest look. Doesn't really know how to handle other resolutions though.

Reminder that AO486 really stands for 486, Pentium class games will be a struggle on Mister, and win95 doesn't game very well.
throAU
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Re: Choice of Correct Resolution Old DOS Games

Unread post by throAU »

Also worth noting that some Pentium class games likely won’t run at all as a lot of them started requiring a decent fpu.
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