Game compatibility for classic computer cores?

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vraskin
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Game compatibility for classic computer cores?

Unread post by vraskin »

Hi everyone. I'm considering buying a MiSTer FPGA pretty much exclusively for the classic computer core support. Specifically I am interested in the Commodore 64, Amiga, MSX, Sharp X68000, and DOS. I can't seem to find any sort of concrete answer with regards to the compatibility percentages for these cores. I understand that the ao486 core for DOS is a work in progress and has limitations, but can't really find any other specifics. The EMUGen wiki lists most of the cores I am interested in as being in "SuperStar" status, but I am not sure what that means exactly. Is it safe to assume that other than the a0486 core I will have close to 100% compatibility?

Thank you!
dshadoff
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Re: Game compatibility for classic computer cores?

Unread post by dshadoff »

Consider the X68000 as a preliminary work in progress.

ao486 has very good compatibility from what I understand - but in a case of "you had to be there", PCs weren't always compatibility with PCs back in the day, and there was an incredible amount of driver-adjustment required for some of the most mundane tasks.... on original hardware. Having said that, there is no math coprocessor on the ao486, so don't expect that to exist.
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Re: Game compatibility for classic computer cores?

Unread post by aberu »

Compatibility percentages are kinda not the correc tway to look at these things regardless. Agreed with dshadoff completely. ao486 you can basically expect that (with you being willing to work on incompatibilities yourself by changing memory managers, etc...) almost anything made before 1995 can run pretty well if not identically. Once you get to the early 3d games and then games that required a "VESA" graphics card, it can get dicey. I noticed Settlers II Gold Edition ran as slow as I remembered it would on my 486DX4 back in the day :D
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vraskin
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Re: Game compatibility for classic computer cores?

Unread post by vraskin »

Thanks for the quick responses guys! That's kind of what I expected re: the ao486 core and I'm fine with that. Any insight into how well the Amiga and Commodore 64 cores work? Those are actually the ones I'm more interested in.
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Re: Game compatibility for classic computer cores?

Unread post by LamerDeluxe »

vraskin wrote: Tue Mar 23, 2021 8:56 pm Thanks for the quick responses guys! That's kind of what I expected re: the ao486 core and I'm fine with that. Any insight into how well the Amiga and Commodore 64 cores work? Those are actually the ones I'm more interested in.
The Amiga (MiniMig) core is mostly cycle-exact when you select the 68000 CPU. I noticed that it can be incorrect when chasing the beam; the shadows of the score sprites in Hybris are not in the right place. I've made a ticket for that quite a while ago, but it hasn't been fixed yet.

The 68020 core is not cycle-exact and can run at about the speed of an 68030 at 50Mhz when you enable d-cache (which a 68020 doesn't have, so that can cause problems). There's also no FPU support, but I don't know of any game that uses that.

The audio of the MiniMig core was improved a lot recently, with more faithful audio generation and the addition of the LED-coupled low-pass filter.

From what I know, almost all games that don't require a very fast Amiga fun absolutely fine on it.

Also good to know is that many cores have game packs available that will let you run hundreds of games without having to configure anything or know specific commands for the computer they are simulating.
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Re: Game compatibility for classic computer cores?

Unread post by Bas »

C64 is so close to the original that I've yet to spot any glitches in any of my original software. The only areas where I see minor differences is in recent demos that push the C64 to it's utmost limits but even those are hardly noticeable to the untrained eye. For all intents and purposes your MiSTer is a C64, unless you really go looking for minute differences.

Same for the Amiga 500 these days with the audio filter update.
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Re: Game compatibility for classic computer cores?

Unread post by rcade »

The only real issue with the C64 core is the disk emulation. It doesn't do flux-level images or even G64's, so only CBM DOS (aka cracked) images will work. No original disks.

If that isn't a feature you need, then no harm done. It works well.
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Re: Game compatibility for classic computer cores?

Unread post by max1602 »

Are the gamepacks usually found on the internet archive? Wo asking for any links...
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Re: Game compatibility for classic computer cores?

Unread post by Bas »

Search engines are your friends. Look for the term TOSEC if you want a huge curated collection.
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Re: Game compatibility for classic computer cores?

Unread post by dshadoff »

I've noticed problems with some TOSEC artifacts.
Dragon (similar to Radio Shack Color Computer) images are not in standard format, omitting portions of headers.
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Re: Game compatibility for classic computer cores?

Unread post by Bas »

I can really only comment on the C64 and Amiga parts of TOSEC and those have been spot-on for me.
vraskin
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Re: Game compatibility for classic computer cores?

Unread post by vraskin »

Thanks again for the feedback everyone. I've had this thing for about a week now and I'm loving it. Currently working on getting full sets for everything.
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darksakul
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Re: Game compatibility for classic computer cores?

Unread post by darksakul »

Keep in mind with the nature of DOS gaming you never have 100% compatibility across all games.
Too many games are built with particular hardware in mind and DOS covers alot of "ground".
Even with FPGA features we can toggle on and off, there only so much you can do.
You also have to factor in your version of DOS that's installed. Some games don't even like to run in Dos and instead must be ran as the boot disk.
It is my great regret that we live in an age that is proud of machines that think and suspicious of people who try to.
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Re: Game compatibility for classic computer cores?

Unread post by ZigZag »

Gamebase64 is great. I just use the gb64 to SD converter to extract the collection with the right names Again, Google is your friend (a friend that's also a nosy bastard).
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