Would a Super Gameboy core be technically possible?

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Stremon
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Would a Super Gameboy core be technically possible?

Post by Stremon »

Hey guys,

I wanted to know if the DE10-nano would be big enough to contain both the Snes and GB logics at the same time (minus the special snes chipsets not needed here) for a SGB core to work on it?
Not asking anybody to make it of course, I'm just curious if it would fit in it, and how technically challenging it would be.
FPGAzumSpass
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Re: Would a Super Gameboy core be technically possible?

Post by FPGAzumSpass »

I don't see why it would not be possible.
You are just asking for SGB playability, so even parts of the SNES would not be needed.

Probably it would be a lot easier to just change the handling of the GB-Core to behave as it would be a SGB.
yoshi41
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Re: Would a Super Gameboy core be technically possible?

Post by yoshi41 »

The SGB is actually a piece of GB hardware (runs a bit faster than the original GB/GBC), which uses the SNES for video out. It allows to use a color palette for grayscale GB games.

If you're looking to play GB games with colors, the GB/GBC core already supports custom palettes (*.gbp).

The core also behaves like a real GBC (of course;), which allows to change the color palette with certain button combinations, at the Gameboy splash screen.

Check this...

https://www.reddit.com/r/nintendo/comme ... color_can/

https://i.imgur.com/jZUXMp2.jpg
MottZilla
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Re: Would a Super Gameboy core be technically possible?

Post by MottZilla »

SGB games can actually access SNES hardware. I think Space Invaders uses this quite a bit. I recall Killer Instinct doing something interesting as well. It's not just the palettes and borders that the SGB can do.

I'm not sure about if the DE-10 can fit all the logic for it or not. I suppose adding the usage of both cores together might give you a rough estimate but it's not going to be very accurate.
normal19
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Re: Would a Super Gameboy core be technically possible?

Post by normal19 »

Should also support Japanese only Super Game Boy 2
jayp76
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Re: Would a Super Gameboy core be technically possible?

Post by jayp76 »

As far as i know the Super Gameboy passes only the Space Invaders (SNES) Rom to the Super Nintendo.
Last edited by jayp76 on Wed Dec 11, 2019 12:24 pm, edited 1 time in total.
jayp76
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Re: Would a Super Gameboy core be technically possible?

Post by jayp76 »

Maybe the Super Gameboy rom already runs on the Snes core. Maybe it just needs the Gameboy Rom loading entry in the Framework.

Edit: Probabably needs Gameboy logic integrated into the core, too.
Stremon
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Re: Would a Super Gameboy core be technically possible?

Post by Stremon »

FPGAzumSpass wrote:I don't see why it would not be possible.
You are just asking for SGB playability, so even parts of the SNES would not be needed.

Probably it would be a lot easier to just change the handling of the GB-Core to behave as it would be a SGB.
It would be needed if you want special SGB palettes, correct 60Hz refresh rate and custom borders ;)
yoshi41 wrote:The SGB is actually a piece of GB hardware (runs a bit faster than the original GB/GBC), which uses the SNES for video out. It allows to use a color palette for grayscale GB games.

If you're looking to play GB games with colors, the GB/GBC core already supports custom palettes (*.gbp).

The core also behaves like a real GBC (of course;), which allows to change the color palette with certain button combinations, at the Gameboy splash screen.

Check this...

https://www.reddit.com/r/nintendo/comme ... color_can/

https://i.imgur.com/jZUXMp2.jpg
The SGB2 runs at the correct speed.
I know how GBC or standard color palettes work, but some games like Kirby Dreamland 2 were optimized to use the SGB hardware to display different color palettes for different zones of the screen, thing the GBC hardware alone (as well as the GB/GBC core) isn't able to do at all. It made those GB games look a bit like GBC games.
Just check online about SGB optimized GB games, you will see the huge difference it makes :mrgreen:
I'm always surprised that only few people seems to know this, and only few emulators actually support it :lol:
MottZilla wrote:SGB games can actually access SNES hardware. I think Space Invaders uses this quite a bit. I recall Killer Instinct doing something interesting as well. It's not just the palettes and borders that the SGB can do.

I'm not sure about if the DE-10 can fit all the logic for it or not. I suppose adding the usage of both cores together might give you a rough estimate but it's not going to be very accurate.
Yeah that's exactly what I am wondering, I have no idea how much usage each of the core is using (minus the snes special chips).

To me the extra advantage we could also get with such core is to also have custom borders and palettes, and have a video output at a standard 240p 60Hz, which would be perfect for analog output without using the scaler.
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Newsdee
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Re: Would a Super Gameboy core be technically possible?

Post by Newsdee »

Stremon wrote: I know how GBC or standard color palettes work, but some games like Kirby Dreamland 2 were optimized to use the SGB hardware to display different color palettes for different zones of the screen, thing the GBC hardware alone (as well as the GB/GBC core) isn't able to do at all. It made those GB games look a bit like GBC games.
If that is all you want, wouldn't it be enough to have the GB/GBC core support a SGB mode that displays the screen border and the additional capabilities? You don't need the full blown SGB SNES interface for that...
Stremon
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Re: Would a Super Gameboy core be technically possible?

Post by Stremon »

Newsdee wrote:
Stremon wrote: I know how GBC or standard color palettes work, but some games like Kirby Dreamland 2 were optimized to use the SGB hardware to display different color palettes for different zones of the screen, thing the GBC hardware alone (as well as the GB/GBC core) isn't able to do at all. It made those GB games look a bit like GBC games.
If that is all you want, wouldn't it be enough to have the GB/GBC core support a SGB mode that displays the screen border and the additional capabilities? You don't need the full blown SGB SNES interface for that...
I don't think that's technically possible, the GBC hardware can't handle those SGB custom palettes, nor the resolution/frequency needed for the borders.

Edit: Just as a reference, I joined a screen capture of how Kirby Dreamland 2 looks on a SGB.
You will clearly see that getting this result is impossible with GBC hardware.
You do not have the required permissions to view the files attached to this post.
yoshi41
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Re: Would a Super Gameboy core be technically possible?

Post by yoshi41 »

Stremon wrote: Just check online about SGB optimized GB games, you will see the huge difference it makes :mrgreen:
Just checked Kirby and DK on my SGB. Right, the colors are better on the SGB, compared to GBC hardware. Definitely an advantage.
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Re: Would a Super Gameboy core be technically possible?

Post by muteKi »

jayp76 wrote:As far as i know the Super Gameboy passes only the Space Invaders (SNES) Rom to the Super Nintendo.
Space Invaders is the only proper SNES-mode game out there, though it has another mode that colorizes the standard game boy mode on the cartridge.

A handful of games also had specific features unique to the SGB:
- A few fighting games supported a 2-player mode, reading in from both SNES controller ports
- A few titles also used the SNES sound hardware to play music/SFX. Animaniacs I think uses the SNES sound exclusively; Donkey Kong uses it to replace the 'Help!' scream sound with an actual 'Help!' sample

Christine Love put out a series of writeups on all the odd Super GB specific features out there, titled 'cluck the Super Gameboy'. (https://loveconquersallgam.es/post/2350 ... troduction)

As another very random note, the Super Game Boy supports a couple macros to do things like speed up and slow down its clock divider that are meant to be pulled off by way of the Hori Game Boy Commander controller. Since these are macros the commands they represent are tied to the BIOS, but would easily be made available if the core could support button macros. I don't possess any of the necessary hardware to see if the clock divider works for the Super Game Boy 2 (my suspicion is that since its clock is part of the cartridge and matches the original GB timing, it doesn't).
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