Gameboy Advance

[skeezix]

Its simple.

An emu is a software system emulating hardware; ie: A _PC_ based emu is usually intel x86 arch.. so its a piece of C code written for intel to support ARM virtual processor, as well as the other cusotm chips and effects in the target system.

Now, if you're actually running on an ARM processor it _may_ not be fully necessary to emulate every little bit.. ie: ARM on x86 coudl sometimes be different than ARM on ARM .. you may be able to skip some of that.

A _port_ is just getting the C code for the emu (Written to be portable, and thus run on x86 and everything else); but as you can see, if you change it, or write it from scratch you can potentially leverage the native processor better.

Consider this angle..

A good full software emu dopes everythign in software, and thus is maximumly portable; but a SNES and GBA can do sprite rotation in hardware, so you emulate it in software.. well and good, and slow on slow machines. But if your native hardware (video card etc) can do rotation, why not emulate that in hardware.. nice and fast. So an emu ideally is written in pure software (max portability), and when brought to a given arch some components can be swapped out to better use the native platform (use hardware scaling say).

This is why a 'basic port' of an emu usually sucks -- its interface is not native feeling, or may be very clumsy; but a port where the author localizes with sweat and blood, it'll be better.. might be the same code, but localized.

Thats why 'recompiling to make it faster' is rediculous; if life were that easy, we wouldn't need developers.

jeff

 

[Series-8]

GBA ARM7TDMI != ARM920

However the 16Mhz ARM7 should be quite possible.

Virtualization tricks with the second core, grabbing all device access with interrupts, shoving them over to a soft-driver... if that kind of stuff can be done with an ARM9 then fullspeed GBA is possible.

However nobody wants to do it. So it won't happen. :mellow:

Unless someone offers to port.

 

[ZodiacfreaK]

I fwhat was said about Nintendo on the first page then I know their secret plan to take over handheld gaming! They will secretly sign up one of their developers on a forum such as this one. Become part of the community then make a gba emu for the system and then nintendo oculd sue the company that made the system! Its foolproof and they could do it over and over again. lol I really dont think that they oculd sue a company just because something runs on it. But you never know with nintendo they patented "online console gaming"

 

[Borgi]

outrage me, but i wouldlike to see gba games on a gp2x :V

 

[vic20-ian]

Not interested in GBA - had one and never played it as I had a GP32 also...........but the emulation problem is interesting.

Picking up on a previous comment about interpreting the rom on the fly -

Would it be possible to process a GBA rom and create a modified "rom" file containing graphic data, sound samples if used and GP2X translated opcodes in a standardised format.

Could this all be done offline on a PC creating a pre interpreted rom?

This file could then be read and run by a GP2X running full speed.

Not truly emulation but a form of offline recompilation that would not look different to a GBA. Not so much dynarec as

I know I have ignored any special accelerator chips and things the GBA may have but am I barking up the wrong tree or just barking? Comments?

 

[DijiTao]

If only ridiculous compiler flags made things run better… (See Gentoo of a great example of just how miniscule a performance increase you get from compiler optimization)

 

[DaveC]

How could Nintendo do anything?  Do they go after PC manufacturers because PCs run perfect GBA emulators?  I think not.

​

Well... PC manufacturers and there is only one firm (and not exactly rich) what is standing behind the gp2x.

Nintendo knows very well that they could have chance only againsts minor players. Few minor PC's firms less that's not big deal for a whole PC industry. However there is only company involved in the gp2x and this is the difference.

It doesn't matter if claims would be bogus. As long one firm has more money then it can drain another to bankruptcy. The best example of such case is the Creative vs Aureal lawsuit. The latter even won but it didn't matter at all.

​

I think they would go after a company that sells much more units. They would go after Palm, Dell, Compaq, anyone that makes a PPC, PDA, cellphone, PC, Sony (the PSP runs Nintendo roms) etc. If anything they would go after Sony, the now arch rival in the home and portable console market, that would be much more worth while. They really can't do much against hardware makers though unless they make emus themselves.

Authors of the emus are a different story. They could claim that the emu maker is infringing on their bogus patents. I think this happened on the zodiac. Nintendo threatened the author of a GBA emu (which was crap anyway) but not Tapwave the maker of the hardware.

 

[skeezix]

As an FYI: Companies don't sue emu makes for profit; they sue to prevent release. Emus don't make profit

jeff

 

[chr15b]

So, eventually will it be possible to run GBA roms on the GP2X?

 

[Segata Sanshiro]

So, eventually will it be possible to run GBA roms on the GP2X?

​

It is already possible to run GBA roms on the Gp2x, at a ridiculous speed though. And also it is potentially possible to run GBA roms on the Gp2x at fullspeed, we just need an emulator that can do it.

Would it be possible to process a GBA rom and create a modified "rom" file containing graphic data, sound samples if used and GP2X translated opcodes in a standardised format.

Hm, isn't that called static recompiling? I looked for it on the net and I found things like this, which seem quite interesting.

But anyway, even in an emulator that works through virtualization, how would the GBA's graphical system (let alone sound) be emulated? I'm talking about hardware-managed sprites, scroll planes, etc. GP Advance does this anyway.

 

[Radek]

How could Nintendo do anything? Do they go after PC manufacturers because PCs run perfect GBA emulators? I think not.

​

Well... PC manufacturers and there is only one firm (and not exactly rich) what is standing behind the gp2x.

Nintendo knows very well that they could have chance only againsts minor players. Few minor PC's firms less that's not big deal for a whole PC industry. However there is only company involved in the gp2x and this is the difference.

It doesn't matter if claims would be bogus. As long one firm has more money then it can drain another to bankruptcy. The best example of such case is the Creative vs Aureal lawsuit. The latter even won but it didn't matter at all.

​

I think they would go after a company that sells much more units. They would go after Palm, Dell, Compaq, anyone that makes a PPC, PDA, cellphone, PC, Sony (the

It would be logical to do so but... we have so called "precedents". Thought there wouldn't be any significant direct gain in courting smaller firm in the what would came from it, the setting of precedent might be considered worth the effort.

Thankfully the GPH isn't considered as serious threat.

PSP runs Nintendo roms) etc. If anything they would go after Sony, the now arch
rival in the home and portable console market, that would be much more worth while. They really can't do much against hardware makers though unless they make emus themselves.

Nintendo can not even be dreaming about touching such giants like Sony. It would eventually just buy offender and case closed. For an example Intel did such thing to DEC. This is quite common practise to kill a lawsuit by buying smaller company (and many wouldn't even resist too hard - it can be very big financial gain for previous owners).

Authors of the emus are a different story. They could claim that the emu maker is infringing on their bogus patents. I think this happened on the zodiac. Nintendo threatened the author of a GBA emu (which was crap anyway) but not Tapwave the maker of the hardware.

​

Single persons are cheap to threaten. Nintendo did it because it didn't cost them anything extra. Imho when company is going to do such thing there inside in a law department no one is thinking seriously that person they are threating would fight back. It could be marketing disaster but rarely somebody will risk almost everything to do alike. It's much safer to just stop.

 

[Sonic-NKT]

look at gpadvance, if this gets ported (only works direct on hardware, cause of full MMU access?) it could be possible. The last version for the gp32 run the ARM7 stuff direct on hardware and used the VBA code for the graphic parts of the gba hardware. it was still quite slow but the VBA code wasnt optimized.
if you could get this running it could be fullspeed with overclocking (without sound) if you optimize the Graphics code (use the special 2D hardware in the gp2x) and then even use the second core it could get fullspeed with sound.
PS: im no Dev but i thinks this is kind of right.