MiSTer FPGA Forum

I don't know if it would be technically possible to make, but it would be nice to get features exclusive to Super Game Boy like special palettes and boarders. I don't know if it could be a modification in the Game Boy core or in the SNES core, its own specific core recriating SNES and Super Game Boy or a core of the Super Game Boy working with the SNES core. Can a core work with another core?! I don't know.

Isn't that not already in the Gameboy core? Just select super gameboy on and a compatible rom. Worked for me just fine

Cebion wrote: ↑Sun Jun 07, 2020 6:31 pm Isn't that not already in the Gameboy core? Just select super gameboy on and a compatible rom. Worked for me just fine

It is present but doesn’t work properly. I tried it with Castlevania and first the graphics corrupt then goes to a black screen It’s unplayable with SGB enabled

In my experience it's very sketchy at moment, not working on the first load of the rom, then staying when you load another, as if there were some kind of memory displacement in time. But I confess since it doesn't support the sound output provided by the SFC and don't like most of the choices of the colour palettes, I just keep it turned off.

Isn't that not already in the Gameboy core? Just select super gameboy on and a compatible rom. Worked for me just fine

The SGB had support for letting the game upload arbitrary code to the SNES's RAM to be executed by the SNES CPU. I don't think that could work unless the SGB core also included a SNES core (or vice versa).

I see, makes sense.
Let's hope then for a proper implementation.

mic_ wrote: ↑Mon Jun 08, 2020 6:10 amThe SGB had support for letting the game upload arbitrary code to the SNES's RAM to be executed by the SNES CPU. I don't think that could work unless the SGB core also included a SNES core (or vice versa).

How many games used that, though? I think only Space Invaders had that ability?
It may be easier to just hack the ROM into two (one for the GB core and one for the SNES core)?

Well, in the interest of hardware preservation, I feel like even these obscure features ought to be supported. Doesn't mean that it should be a top priority or anything, but if you only have the palettes and the borders then it's not really a Super Gameboy.

In addition to the pallets/borders, SGB allowed for multiplayer on some GB games, even multitap for the Bomberman games
https://en.m.wikipedia.org/wiki/List_of ... _Boy_games

Would be amazing to see this. I'll be keeping an eye on the SD2SNES WIP that just popped up.

With a good GB/GBC core and other easy ways to play the games on TV this will be a very low priority request but I would personally love seeing it implemented, having owned a SGB growing up. Donkey Kong was amazing with it and it's just not the same playing it without the SGB improvements.

Did this just drop? I was never able to get the SGB palettes and borders to work and now it does?

The new enhancements are really great! I'm enjoying the new audio filters and playing Donkey Kong '94 in SGB mode.
Would it be complicated to implement 2-player/multitap for the SGB games that support it? There's about 30 of them.

Newsdee wrote: ↑Tue Jun 23, 2020 3:26 am The new enhancements are really great! I'm enjoying the new audio filters and playing Donkey Kong '94 in SGB mode.
Would it be complicated to implement 2-player/multitap for the SGB games that support it? There's about 30 of them.

Where are these audio filters? I don't quite understand what they are, much less where to find them.

retrorepair wrote: ↑Tue Jun 23, 2020 1:54 pmWhere are these audio filters? I don't quite understand what they are, much less where to find them.

There's an "audio filters" option now available on the same screen where you can select video filters. But the updater script has pulled any actual filters down yet, and I don't see any looking at the GitHub. Presumably the idea here is that you can apply a filter to do things like emulate the tinny sound of the actual GB speaker, or maybe one that lets you choose between different Genesis revision sounds.

Sigismond0 wrote: ↑Tue Jun 23, 2020 4:12 pm There's an "audio filters" option now available on the same screen where you can select video filters. But the updater script has pulled any actual filters down yet, and I don't see any looking at the GitHub. Presumably the idea here is that you can apply a filter to do things like emulate the tinny sound of the actual GB speaker, or maybe one that lets you choose between different Genesis revision sounds.

Do you think that a Gameboy bezel (like the Super Gameboy offers) would be one of the video filters perhaps?

OnCor wrote: ↑Tue Jun 23, 2020 4:30 pmDo you think that a Gameboy bezel (like the Super Gameboy offers) would be one of the video filters perhaps?

No. Video filters are things like scanlines, interpolation, etc. Selectable borders would have to be an entirely new feature.

Sigismond0 wrote: ↑Tue Jun 23, 2020 7:32 pm No. Video filters are things like scanlines, interpolation, etc. Selectable borders would have to be an entirely new feature.

Ah, I see. Thanks!

retrorepair wrote: ↑Tue Jun 23, 2020 1:54 pm Where are these audio filters? I don't quite understand what they are, much less where to find them.

It's still a work in progress, but it should become available via the updater at some point.

Newsdee wrote: ↑Wed Jun 24, 2020 6:20 am

retrorepair wrote: ↑Tue Jun 23, 2020 1:54 pm Where are these audio filters? I don't quite understand what they are, much less where to find them.

It's still a work in progress, but it should become available via the updater at some point.

I see there are some example filters in the Main repo. It sounds interesting (pun intended).

EvilRyu wrote: ↑Mon Jun 22, 2020 4:00 pm Did this just drop? I was never able to get the SGB palettes and borders to work and now it does?

The first version with SGB support was released in the beginning of May. Maybe you had it set to Gameboy Color mode? It only works in Gameboy mode.

Newsdee wrote: ↑Tue Jun 23, 2020 3:26 am Would it be complicated to implement 2-player/multitap for the SGB games that support it? There's about 30 of them.

There you go : https://github.com/MiSTer-devel/Gameboy ... 19a4151f8c

EvilRyu wrote: ↑Mon Jun 22, 2020 4:00 pm Did this just drop? I was never able to get the SGB palettes and borders to work and now it does?

In my experience there are issues with it. Castlevania Legends, for example, has corrupted graphics in SGB mode and eventually hangs at a mostly blank screen

So how to we feel about supporting the "speed" button on the SGB controller?

I'm a little confused about the state of SGB emulation: currently the screen can be shrunk down with a black border, and the SGB color pallet can be applied to non GBC games. Is that the extent of it? Is there a point in me loading up "SGB Enhanced" roms? Will any of those enhancements come through?

Edit: after some fidgeting I got boarders to work for enhanced games: not sure if I was being impatient, or if it has something to do with having the System set to Auto.

Things that the SGB effects in the core don't replicate:
- Specific SGB interface -- including user-customizable coloration, borders, and animations (and a credits sequence), and these are different between the two SGB models.
- Fade-out from Super GB border into game-specific one (not a particularly noteworthy feature on its own)
- Use of SPC-700, for sound effects or music (i.e., Donkey Kong, Animaniacs) -- in SGB mode no audio plays. The only emulator I know of that supports this properly is bsnes/Higan, and unlike colors or borders I doubt a simple high-level solution for this exists.
- Space Invaders including a memory-resident SNES copy of the game, but this feature isn't as useful when you're not playing it from an actual GB cart anyway; there's a perfectly good SNES-specific copy of the game (and a very nice SNES core), after all.
- Use of the SNES clock to replicate the specific gameplay speed of the SGB1. Having looked into it a little more I do believe that the Hori GB Commander could be used to downclock both the original the SGB2 as well, though I don't know what the SGB2 alternate clock speeds are (see here, where it used with the SGB2: https://www.youtube.com/watch?v=blxuKsQCQGI).

Of these the only one I personally care about on a level stronger than "that would be nice to have I guess" is some way to replicate the SPC-700 sound effects.

Is it really even appropriate for SGB functionality to be in the Game Boy core long-term? I know it's typical of Game Boy emulators to have it, but wouldn't it be be more accurate for the SGB functionality to be moved to the SNES core instead? After all, the Super Game Boy is really an add-on for the SNES (like the BS-X), and not a true Game Boy.

jlancaster86 wrote: ↑Mon Oct 26, 2020 9:54 am Is it really even appropriate for SGB functionality to be in the Game Boy core long-term? I know it's typical of Game Boy emulators to have it, but wouldn't it be be more accurate for the SGB functionality to be moved to the SNES core instead? After all, the Super Game Boy is really an add-on for the SNES (like the BS-X), and not a true Game Boy.

Totally agree with this. True SGB support in the gameboy core would mean moving the SNES core over to it which would make it much bigger than it needed to be.

Moving the gameboy core (or parts of it) to the SNES core makes much more sense.

I think the big problem with the SNES core is that it's close to full with all the other various mappers and hardware extensions.

I would be interested in a core that forked off the SNES core with the sole purpose of implementing super game boy stuff with proper accuracy, though. I think it's fine if it's separate from this which I think of as more of a GBC / Game Boy Player sort of core.

the_muteKi wrote: ↑Fri Oct 30, 2020 11:36 pm I think the big problem with the SNES core is that it's close to full with all the other various mappers and hardware extensions.

I would be interested in a core that forked off the SNES core with the sole purpose of implementing super game boy stuff with proper accuracy, though. I think it's fine if it's separate from this which I think of as more of a GBC / Game Boy Player sort of core.

For what it's worth, I totally agree with this approach. While it logically makes sense for SGB/SGB2 functionality to be a part of the SNES core, if it's so full then setting it up as a separate core only for GBC/GB games makes all the sense in the world.

Now we just have to find someone to make the core!