Homebrew Emulation GameYob, a gameboy emulator for DS

[dickfour]

I'd like to see gbc bios support

 

[Normmatt]

I'm going to go with Github, thanks for the suggestions.

C++, not that it uses many C++ features. I have a half-finished asm core which can fall back to the c++ core for unfinished instructions... I stopped because I wasn't convinced my hand-made assembly would be any better than the compiler. But I might as well finish, I think there's just the bit-manipulation opcodes remaining.

Actually I kind of like lameboy's brutalist approach to menus. Fancy UIs aren't really my thing, plus it's really quick to throw in some temporary debugging options this way... I could probably at least get a font that's nicer to look at. Cheats, palettes, and wifi linking are definitely on my to-do list.

Could you add that asm core as a branch on github? I bet it could be optimized by using the goomba color asm core as a guide.

 

[2ndApex]

Can someone link me to a SDK/quick tutorial on how to compile NDS code?

 

[Drenn]

Can someone link me to a SDK/quick tutorial on how to compile NDS code?

http://devkitpro.org/wiki/Getting_Started/devkitARM
Good luck.

Could you add that asm core as a branch on github? I bet it could be optimized by using the goomba color asm core as a guide.

It's broken at the moment, due to general changes in layout. I'll try to get it working again and I'll add it.

 

[Normmatt]

One thing too note is your emulator fails some of the tests from http://slack.net/~ant/old/gb-tests/ theres some cpu bugs which might be causing some games to break. Timing might also be causing some stuff to break but thats harder to fix...

 

[RupeeClock]

Finally, an alternative to Lameboy for the DS.

I got straight to testing a bug that impeded progress in Mega Man V.
On Lameboy, selecting Saturn on the boss select screen would crash the game, making the game impossible to clear.
Testing the same scenario on GameYob, it did actually get passed the crash, but still have some unusual slowdown before actually playing the introduction animation, and then going to the stage.

It looks like there's a problem with selecting Saturn on Mega Man V when the emulation is still not correct, but the good news is that you can actually play the game on GameYob now.
I did notice that the sound was not accurate, as you said there may be issues, but I am hopeful that this project goes well, and that Lameboy will be superseded.

 

[Drenn]

One thing too note is your emulator fails some of the tests from http://slack.net/~ant/old/gb-tests/ theres some cpu bugs which might be causing some games to break. Timing might also be causing some stuff to break but thats harder to fix...

Hmm, thanks... for some reason the interrupt tester doesn't give any output, it just sits there so I can't see exactly what the problem is.
I was able to fix a few problems with flags, but I don't know about instructions E8 and F8. I'd better take a look at Gambatte.

Finally, an alternative to Lameboy for the DS.

I got straight to testing a bug that impeded progress in Mega Man V.
On Lameboy, selecting Saturn on the boss select screen would crash the game, making the game impossible to clear.
Testing the same scenario on GameYob, it did actually get passed the crash, but still have some unusual slowdown before actually playing the introduction animation, and then going to the stage.

It looks like there's a problem with selecting Saturn on Mega Man V when the emulation is still not correct, but the good news is that you can actually play the game on GameYob now.
I did notice that the sound was not accurate, as you said there may be issues, but I am hopeful that this project goes well, and that Lameboy will be superseded.

It does something that Lameboy doesn't? Awesome. I really hope I can get the sound sorted out.

 

[RupeeClock]

It does something that Lameboy doesn't? Awesome. I really hope I can get the sound sorted out.

Uh huh, and as I recall Lameboy had problems with certain boss battles in Super Mario Land 2 as well, such as the Tree Zone boss.
If you want to test out the Mega Man V bug, here's a password you can use in-game.

R E T E _
_ _ T _ E
T E T _ T
T T E E T
T T T E R

That password will bring you straight to the boss selection screen. Saturn is the top-right boss and it should be pretty obvious what is wrong when you try selecting him on Lameboy or GameYob, compared to other boss selections.

I also tested this bug on OhBoy on my GP2X Caanoo and that had no such problem.
Now that I think about it, OhBoy is an open-source emulator too. It has compiles for desktop x86 (Win/Linux), MIPS devices such as the Dingoo A320/GCW Zero, and ARM devices like the GP2X Caanoo.
http://code.google.com/p/ohboy/
It stands to reason that you could study the source code for this emulator to improve your own.

 

[Drenn]

Uh huh, and as I recall Lameboy had problems with certain boss battles in Super Mario Land 2 as well, such as the Tree Zone boss.
If you want to test out the Mega Man V bug, here's a password you can use in-game.

R E T E _
_ _ T _ E
T E T _ T
T T E E T
T T T E R

That password will bring you straight to the boss selection screen. Saturn is the top-right boss and it should be pretty obvious what is wrong when you try selecting him on Lameboy or GameYob, compared to other boss selections.

I also tested this bug on OhBoy on my GP2X Caanoo and that had no such problem.
Now that I think about it, OhBoy is an open-source emulator too. It has compiles for desktop x86 (Win/Linux), MIPS devices such as the Dingoo A320/GCW Zero, and ARM devices like the GP2X Caanoo.
http://code.google.com/p/ohboy/
It stands to reason that you could study the source code for this emulator to improve your own.

I see what you mean, and some bosses in the first half have that slowdown too. I'll check it out.

Also I just noticed something, maybe I shouldn't even mention it or I'll make people paranoid... but sound in gameyob is the tiniest bit faster than on a real gameboy. Probably the game runs slightly faster due to the ds's lcd timings. That must be why I needed a hack to make Pikachu's voice sound better...

 

[mikeyisdead]

i think it's a good idea to use ohboy source and use few the Features that has
maybe would make it little more better than before if you think about it

 

[deshayzilla]

This all sounds pretty awesome. Can't wait to see how far this project goes. If it can get to the point where we can do RGBY Pokemon trading I think I'll be set for life with pokemon games!

 

[TheLostSabre]

YES! YES! YES!

Finally another gameboy emulator! While lameboy is great, it practically dead now and with no open-sources it might as well be dead. I hope this emulator will be even greater! Much can be done with this emulator since the source is open. I wholeheartedly support this project!

 

[Sicklyboy]

This finally got frontpaged. Congrats, man.

 

[Drenn]

Since at least 3 people asked me yesterday, the gbc bios is supported now. I'll update the first post with details. Also I'm going to stop incrementing the version number with small changes, and I'll be putting a binary of the latest build on dropbox rather than being mixed with the source on github. But I'll put new version numbers in the "bin" directory on github.

Edit: First post updated. You need to download the latest build from the dropbox link for bios support.

Edit: Crap. I broke something when the bios file isn't available. I'll fix it shortly...

Edit: Should be fixed now.

 

[BLsquared]

Finally, an alternative to Lameboy for the DS.

I got straight to testing a bug that impeded progress in Mega Man V.
On Lameboy, selecting Saturn on the boss select screen would crash the game, making the game impossible to clear.
Testing the same scenario on GameYob, it did actually get passed the crash, but still have some unusual slowdown before actually playing the introduction animation, and then going to the stage.

It looks like there's a problem with selecting Saturn on Mega Man V when the emulation is still not correct, but the good news is that you can actually play the game on GameYob now.
I did notice that the sound was not accurate, as you said there may be issues, but I am hopeful that this project goes well, and that Lameboy will be superseded.

YAY! Finally, Saturn works!!! Thank you!
*goes to complete MMV*

 

[loco365]

I'm already anxious to try this out, and I'm definitely looking forward to SGB Border support. The border for Pokemon Red (And Blue I presume) is partially broken in Lameboy.

Edit: Can I make one tiny request? Perhaps adding a gbs player would definitely make this emulator stand out.

 

[Clydefrosch]

i'm wondering, when more work is put into this, would it be able to run shantae at full speed?
or is this game just too hard to emulate in general, as it even has problems working on a psp

 

[Drenn]

I'm already anxious to try this out, and I'm definitely looking forward to SGB Border support. The border for Pokemon Red (And Blue I presume) is partially broken in Lameboy.

Edit: Can I make one tiny request? Perhaps adding a gbs player would definitely make this emulator stand out.

The borders in the pokemon games seem to fix themselves when you reset emulation. But that's just annoying. I'll add gbs playback to the list, but it'll be near the bottom.

i'm wondering, when more work is put into this, would it be able to run shantae at full speed?
or is this game just too hard to emulate in general, as it even has problems working on a psp

It's tough to say, it's probably possible, but it would take a ton of optimization. Luckily some of the graphical glitches disappear when "wait for vblank" is enabled, which means when fullspeed, those glitches would fix themselves. But yeah, it's one of the more intense games to emulate.

 

[Drenn]

I fixed the slowdown for megaman. Actually, by all rights it should have crashed when selecting those robot masters which caused lag - that's what happened after the slightest change. Interrupt timing issues... anyway it's fixed now, and it only fails one of the cpu tests.

 

[TheLostSabre]

You work really fast. O_O

Kudos to you. ;]