PC 386 and 286 Core Setup Ideas

[suww37]

memories of having fun with the XT monochrome monitor and hercules

I've tried making a monochrome mode for ao486.
It's a long shot ... and I may not merge it (I'm by no means a core developer), but it's an interesting experiment.

The rbf attached use the same algo as the PCXT core but extended to 8-bit color. It doesn't work well with EGA or VGA yet - I'm probably missing something - but CGA converts nicely, and if you add scanlines it does look quite similar to my old Apple II monochrome monitor.

The difference between setA and setB are coefficients used in the algo, which give different results in contrast between CGA colors.
Which one do you guys like best?
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green486_setA.zip
green486_setB.zip

ddragon.png

Thank you for trying your ao486 core monochrome effect. However, unlike the PCXT core monochrome CGA, the screen is very dark, cloudy, and not clear.

[suww37]

Here is a first unofficial build release of a monochrome mode for ao486.
Don't expect it to be merged ... but I've included the HDL changes in the zip file, if anybody wants to tinker with it.

I sacrificed some OSD flags to have space for the Display Mode menu;
there are now a few monochrome options, including the original four and some others added for fun that look quite good.

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ao486_monochrome.zip
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mk2a.png
mk2r.png
osd_options.jpg

I tested it, it got a lot better. Thank you so much for your hard work. I'll use it well ^^

[Newsdee]

I found a nice slowdown program that works with ao486:
http://www.ibiblio.org/pub/micro/pc-stu ... wdown.html

It's pretty easy to use, for example to set it at 12Mhz for Death Track:

Code: Select all

SLOWDOWN.EXE /Mhz486:12

And for Megaman 25Mhz works best:

Code: Select all

SLOWDOWN.EXE /Mhz486:25

dtrack.png (33.27 KiB) Viewed 1858 times

[suww37]

I found a nice slowdown program that works with ao486:
http://www.ibiblio.org/pub/micro/pc-stu ... wdown.html

It's pretty easy to use, for example to set it at 12Mhz for Death Track:

Code: Select all

SLOWDOWN.EXE /Mhz486:12

And for Megaman 25Mhz works best:

Code: Select all

SLOWDOWN.EXE /Mhz486:25

dtrack.png

The speed down utility like "slowdown" is that there is a problem that the frame is not smooth and skip. So I can never get the feeling of being at the actual AT pc. And the monochrome mode ao486 you uploaded is different from pcxt's mochrome mode, and the contrast of the cga is not well represented.

[Newsdee]

And the monochrome mode ao486 you uploaded is different from pcxt's mochrome mode, and the contrast of the cga is not well represented.

it's exactly the same code in both cores But I wonder if the CGA palette of ao486 might be slightly different as PCXT so doesn't have as good a contrast.

[NightShadowPT]

Assuming this monochrome add-on is working well, is there a reason why it could not be integrated into the main ao486 core? It's not like it branches out in a completely different direction, it just gives users one more option.

I for one, would love to have it in the main core as I have played many MS-DOS games either on an Amber or Black&White screen.

Anyway, thanks for creating this mod... really appreciate your work.

[Newsdee]

Assuming this monochrome add-on is working well, is there a reason why it could not be integrated into the main ao486 core? It's not like it branches out in a completely different direction, it just gives users one more option.

It's not reallly worth the effort.giveb the way the core is right now.

It requires two or three OSD status bits (for either 4 monochtome modes or all 8 of them). These bits are all used up in the core, and can't easily be extended without a wider changes to the core .. which would need a lot of retesting.

That said, if that extension were made independently (for some more important feature), then this could be added after relatively easily.

[aberu]

You can double the number of status bits very easily to 128 now.

https://github.com/MiSTer-devel/Templat ... e929fe8b5c

But just because you can add something doesn't always mean it's the right thing to add

[jordi]

https://github.com/jamieiles/80x86

Is this portable?