Homebrew The Truth behind GBA emulation

[Extreme Coder]

Maybe it would be best if we'd try to get a team of DS homebrew devs. to work on this, maybe then we'll see something that works.

I doubt you'd find homebrew devs willing to do this. I mean, they program what they want to do, not what the warez scene wants to do.

QUOTE(Whizz @ Jan 22 2008 @ 06:03 PM)I wrote a PS3 emulator for the DS. I won't release it because I'm affraid of it being used for piracy.

I hope you can get atleast ~40 FPS with it

Also, does it stutter when it loads ISOs over 5 GB?

 

[Extreme Coder]

I wrote a PS3 emulator for the DS. I won't release it because I'm affraid of it being used for piracy.

I hope you can get atleast ~40 FPS with it

Also, does it stutter when it loads ISOs over 5 GB?

 

[Rayder]

I still think it's ridiculous to even attempt GBA emulation on the DS. THE DS SUPPORTS GBA IN SLOT2! It's one thing to pirate every game on the system, it's another to be too cheap to buy a slot2 card to play GBA games with.


Just buy a slot2 card. Silly discussion about emulating hardware that's already supported then becomes moot.

 

[imz]

Whoever made the concept should definitely either release a video, or pictures, otherwise we can just forget it.

I'm not sure whether to believe it or not, so some proof would be nice...

Amen

I'm not falling for that crap again which I did with a certain IGN editor (yes I'm talking about halo DS)

 

[pika3000]

Amen

I'm not falling for that crap again which I did with a certain IGN editor (yes I'm talking about halo DS)

He released a video for it, although it looked like an edited version of Goldeneye: Rouge Agent

 

[rest0re]

liraluna did it

 

[flai]

Oh wow.

 

[Wuschmaster]

Sounds like bullsh1t

 

[elfsander]

I still think it's ridiculous to even attempt GBA emulation on the DS. THE DS SUPPORTS GBA IN SLOT2! It's one thing to pirate every game on the system, it's another to be too cheap to buy a slot2 card to play GBA games with.


Just buy a slot2 card. Silly discussion about emulating hardware that's already supported then becomes moot.

Did you even READ it? This is NOT about emulating a GBA, this about making a hypervisor to support GBA games using DS hardware.

 

[Grimalkin]

Did you even READ it? This is NOT about emulating a GBA, this about making a hypervisor to support GBA games using DS hardware.

Calm down.

I'd like at least a proof of concept. Especially how the hypervisor would regulate the memory.

 

[Nio]

I was so excited when I read my RSS, but after reading the post, I feel fucked ... thats shit ...

 

[elfsander]

Did you even READ it? This is NOT about emulating a GBA, this about making a hypervisor to support GBA games using DS hardware.


Calm down.

I'd like at least a proof of concept. Especially how the hypervisor would regulate the memory.

Sorry the quote wasn't correctly included. And I am calm.

 

[lenselijer]

lol, this is all just a joke.

The anonymous programmer is concerned about the implications of piracy so the concept demo will not be released

sure, the gba isnt even sold in stores anymore for a long time here, same goes for the games. and why not release a proof of concept of some gba demo playing instead? that wont harm anyone

 

[jalaneme]

I still think it's ridiculous to even attempt GBA emulation on the DS. THE DS SUPPORTS GBA IN SLOT2! It's one thing to pirate every game on the system, it's another to be too cheap to buy a slot2 card to play GBA games with.


Just buy a slot2 card. Silly discussion about emulating hardware that's already supported then becomes moot.

exactly, this emulator thing is pointless.

 

[azotyp]

Just buy a slot2 card. Silly discussion about emulating hardware that's already supported then becomes moot.

Thinking that way I could say that it is stupid to play nds games on supercard for slot 2 with flashed nds, because they exist on slot 1. I say this is revolution, maybe in few years nobody will use slot 2 anymore. (or maybe not

).

 

[jenngcia]

Isn't Nintendo prepping some kind of downloadable gba games for sale soon? Bet somebody can hack that and get it to work with slot-1 flashcarts...

 

[Exophase]

Registered so I can clear this up, a lot of people are getting excited over something fundamentally flawed.

Guys, you can't do a hypervisor that'll run at real time speed because the Nintendo DS doesn't have an MMU, it has an MPU. That letter makes a huge difference. Let me explain how this works:

A "hypervisor", or virtual machine manager is code that virtualizes a platform so that it appears to the client code (whatever you're trying to virtualize) that it's running on that machine. Some decades ago a set of standards were written up determining what a virtualization environment must include to properly work (http://en.wikipedia.org/wiki/Popek_and_Goldberg_virtualization_requirements). The code must behave exactly as it can on the original machine, the VMM must be in control of the resources, and it has to be efficient. If you take out the third category then technically any emulator could pass so it really is important. Any ARM9 will fail the first two of these because there are sensitive resources which can't be trapped (like PSR status, SWIs, etc) but for games it might not matter, if they don't depend on this accuracy. The third part you won't ever get w/o an MMU.

An MMU is necessary because it translates one address space to another and traps accesses to memory mapped devices, you can NOT do this efficiently with an MPU. All you can do is make it trap on every address space mapping that doesn't match the original (and even this capacity is limited). In the DS's case the entire cart bus won't be properly mapped to an actual ROM like the GBA game will expect, meaning that every single instruction fetch from ROM would have to be trapped. GBA games run on average about 60% of their code from ROM. This would be much slower than a recompiler by far (which can translate the code into RAM instead of ROM). In fact, it'd probably be slower than an interpreter too, because when the code isn't running from RAM that's essentially what it will be - each trap will have to be decoded to determine what kind of memory access it is and then mapped to emulated ROM. Of course this also includes the paging of said ROM in and out of RAM like others have mentioned but that'd just be an afterthought in performance degradation when compared to the primary costs.

No offense to Normmatt, but as the co-author of a DS emulator I expected you to already know all of this.

Now it's time for the usual, fending off all the people who say "anything is possible" and back it with anecdotal evidence, or that I don't know what I'm talking about compared to those who they heard were involved. That is, if everyone doesn't ignore this post altogether.

 

[cracker]

Isn't Nintendo prepping some kind of downloadable gba games for sale soon? Bet somebody can hack that and get it to work with slot-1 flashcarts...

That's what I'm thinking the built-in storage in the DS Lite 2 (DS Liter?) will be used for. No doubt it will use some kind of encryption to lock downloaded games into one system and prevent unauthorized games from playing on systems like VC on Wii and the N64 iQue.

 

[dib]

The possibility or impossibility is irrelevant, without a demonstration it hasn't happened.

Oh yeah and HAY GUYS I GOTS NINTENDO 64 RUNNING ON MY DS! FOR REALS! I JUST CONNECTED THE PROCESSOR MATRIX TO THE FLUX CAPACITOR AND CUT THE N64 CART CONNECTION DOWN TO THE SIZE OF THE DS THEN PLUGGED IT IN AND IT TOTALLY WORKS YOU SHOULD BELIEVE ME.

 

[amptor]

sounds good, hopefully we'll see this working possibly with sound in the future. would be good to have all games in one cart, rather than lugging around multiple carts for gaming and trying to figure out which gba cart is the best one to use.