Homebrew GNUBoy 3DS

[RetroGamer02]

Hi everyone I have been working on porting the GNUBoy GameBoy Color Emulator to the 3DS but I feel like it still needs some testing.

The Menu is accessed with the Y button.
The L Trigger is quick save and R Trigger is quick load.

If anyone would be willing to help that would be great. =)

I hope you enjoy!

Source: https://github.com/RetroGamer02/gnuboy-3ds

Download: https://github.com/RetroGamer02/gnuboy-3ds/releases/tag/3ds-V0.5.3

 

[CoolMe]

How's the emulation if you don't mind me asking?

 

[RetroGamer02]

How's the emulation if you don't mind me asking?

I personally find it fine.

 

[ber71]

I personally find it fine.

Better than (standalone) mgba? which is unplayable slow with some demanding GBC titles, on old3ds.

In the other hand, gameyob-3ds sucks, and gameyob-dsi runs fine but seems blurry because of the additional scaling.

 

[RetroGamer02]

Better than (standalone) mgba? which is unplayable slow with some demanding GBC titles, on old3ds.

In the other hand, gameyob-3ds sucks, and gameyob-dsi runs fine but seems blurry because of the additional scaling.

I only have a Old 3DS and it works fine. =)
It also has linear scaling.

 

[XRTerra]

Better than (standalone) mgba? which is unplayable slow with some demanding GBC titles, on old3ds.

In the other hand, gameyob-3ds sucks, and gameyob-dsi runs fine but seems blurry because of the additional scaling.

Yeah, I've noticed that specifically GB/A emulators on the 3ds just aren't super amazing.

I'm loading my 3ds with some GB/C roms right now and gnuboy(obviously). But having a good gameboy emulator could also pave the way for fullspeed gba on an old3ds(which should definitely be possible).

Post automatically merged: Jul 11, 2023

For the first few tests I've been doing, they all run well.

OG Gameboy games have pretty warm colors(I have to set my screen temperature to 8000k for it to look black and white.

A romhack I have of Castlevania II: Belmont's revenge was probably the perfect test for this. Game ran well but there were stutters/a choppy frame rate that isn't present on mGBA(infact, a few games had this, nothing crazy though). Colors did look exactly like they do on mGBA. I tested it on an n3ds, both with regular clocks and downclocked to o3ds speeds. At o3ds speeds, it runs better than mGBA, infact, it runs better than n3ds speeds which run the games choppier than o3ds speeds. The issue seems to be with 804mhz and not the l2 cache.

Overall, for being a young emulator, this is amazing, outside of n3ds fps issues.

My only real issue is that you have to press the dpad down multiple times depending where your roms folder is. May I suggest that gnuboy automatically looks for a "roms/gb" path or "/roms/" path in general?

 

[RetroGamer02]

Yeah, I've noticed that specifically GB/A emulators on the 3ds just aren't super amazing.

I'm loading my 3ds with some GB/C roms right now and gnuboy(obviously). But having a good gameboy emulator could also pave the way for fullspeed gba on an old3ds(which should definitely be possible).

Post automatically merged: Jul 11, 2023

For the first few tests I've been doing, they all run well.

OG Gameboy games have pretty warm colors(I have to set my screen temperature to 8000k for it to look black and white.

A romhack I have of Castlevania II: Belmont's revenge was probably the perfect test for this. Game ran well but there were stutters/a choppy frame rate that isn't present on mGBA(infact, a few games had this, nothing crazy though). Colors did look exactly like they do on mGBA. I tested it on an n3ds, both with regular clocks and downclocked to o3ds speeds. At o3ds speeds, it runs better than mGBA, infact, it runs better than n3ds speeds which run the games choppier than o3ds speeds. The issue seems to be with 804mhz and not the l2 cache.

Overall, for being a young emulator, this is amazing, outside of n3ds fps issues.

My only real issue is that you have to press the dpad down multiple times depending where your roms folder is. May I suggest that gnuboy automatically looks for a "roms/gb" path or "/roms/" path in general?

Thank you for the excellent feedback! I have attached a version of the emulator that will hopefully only enable the l2 cache for now since I only have an old model 3ds this will specifically need testing. If you would be so kind as to let me know if it runs better that would be great. I don't know why the higher clock speed causes trouble yet. I also set the rom directory to the roms on the sd cards root sdmc:/roms.

 

[XRTerra]

Thank you for the excellent feedback! I have attached a version of the emulator that will hopefully only enable the l2 cache for now since I only have an old model 3ds this will specifically need testing. If you would be so kind as to let me know if it runs better that would be great. I don't know why the higher clock speed causes trouble yet. I also set the rom directory to the roms on the sd cards root sdmc:/roms.

It crashed after opening my GB file after it boots to the Roms section. I'm determined to test a game out though, so I'm going to put a gb game just in the root of /roms/

Game works fine, but it doesn't enable the L2 cache(probably conflicting with Luma's settings) so I'm gonna do some troubleshooting to see if I can get it to enable the l2.

 

[RetroGamer02]

It crashed after opening my GB file after it boots to the Roms section. I'm determined to test a game out though, so I'm going to put a gb game just in the root of /roms/

It could be I did not do the N3DS Cache setting properly. If so try this one that has no New 3DS Specific code.

 

[XRTerra]

It could be I did not do the N3DS Cache setting properly. If so try this one that has no New 3DS Specific code.

Both versions crash.

 

[RetroGamer02]

Both versions crash.

It seems to be the romdir code oddly. Ill try to get it working right odd though since it worked fine in the emulator but not the real thing. Please forgive the crashes.

 

[Mr_Start]

Does it has RTC save file?

 

[RetroGamer02]

Does it has RTC save file?

It has RTC yes.

Post automatically merged: Jul 12, 2023

New version: https://github.com/RetroGamer02/gnuboy-3ds/releases/tag/3ds-V0.5.2

• Changed Y from exit to menu.
• Hopefully fixed issues on New 3DS.
• Video mode may be changed from the menu but it does not save yet.
• Rom directory is now /roms/ on the sdcard.

 

[CrashMidnick]

Thanks RetroGamer02 for this emulator. I did not test previous versions but on my side I noticed this (only tested on O3DS at the moment) :
- games are not smooth, it is like there is frameskip
- speed in some games seems to be too fast (i.e. DK country GBC)
- For some reasons, the file browser does not see some of my roms

What could be great :
- DMG "green" colour for GB games
- scroll faster the game list
- the Police is not that good to be honest, it is diffult to see some letters (i.e. "B" looks like a "E")

 

[RetroGamer02]

Thanks RetroGamer02 for this emulator. I did not test previous versions but on my side I noticed this (only tested on O3DS at the moment) :
- games are not smooth, it is like there is frameskip
- speed in some games seems to be too fast (i.e. DK country GBC)
- For some reasons, the file browser does not see some of my roms

What could be great :
- DMG "green" colour for GB games
- scroll faster the game list
- the Police is not that good to be honest, it is diffult to see some letters (i.e. "B" looks like a "E")

I will do what I can to fix these issues and thank you very much for the feedback.
If you want to I can send you a dev build and you could tell me if speed issues persist.

Post automatically merged: Jul 14, 2023

New version: https://github.com/RetroGamer02/gnuboy-3ds/releases/tag/3ds-V0.5.3

Can load bios from /3ds/GNUBoy/
If using bios please use both gb and gbc bios roms or it could cause errors.
Speed Ups
More Video Options
Actual DMG Colors for GB games
Fixed 2 small sound bugs.
New 3DS Enhancements are disabled until they can be properly tested.
Can use left and right in menu to skip a few items.
Dpad movements should now be correct had some occasional odd movements before.
Joystick has been disabled for now its code still needs to be rewritten when I can.

 

[worm28]

I cant wait to try this i have wanted a good gameboy (color) emulator since i modded my 3ds any chance we can get a
GNUBoy CIA?

 

[RetroGamer02]

I cant wait to try this i have wanted a good gameboy (color) emulator since i modded my 3ds any chance we can get a
GNUBoy CIA?

I just added a cia version. =)

 

[CrashMidnick]

If you want to I can send you a dev build and you could tell me if speed issues persist.

Sure I will test them. I can test N3DS builds as well

 

[RetroGamer02]

Sure I will test them. I can test N3DS builds as well

Nice also what roms did the selector not see? What extension did they have and when you said the Police is not that good I assume that's a game?

 

[CrashMidnick]

Nice also what roms did the selector not see? What extension did they have and when you said the Police is not that good I assume that's a game?

It does not see some standard .gb and .gbc roms. For example I have a mario.gb (super mario land) that is not showing in the browser. I had to download another rom. My Zelda roms are also affected. I need to investigate because I have some .sav files generated by other emulators.
About the Police, I talk about the rom browser.

EDIT : TESTED the previous build 0.5.2 on N3DS and it works on my side. The emulator behave the same as on O3DS : no smooth scrolling but full speed on all games except few GBC games such as Aladdin or DKC.