#172082 - cantab - Thu Jan 14, 2010 1:38 am
Is it possible to run a GBA ROM on a Nintendo DS with only a slot 1 device?
I've looked around, and everything I've come across has said no - but I haven't come across anything recent (mostly it's forum discussions from like 2008 or earlier), so I'm wondering if there's been any recent developments?
#172085 - dantheman - Thu Jan 14, 2010 6:37 am
GBA homebrew (please read the forum rules) can only be emulated from the slot-1 iPlayer cart, which has upgraded hardware originally meant to be used for playing back unconverted video files. The emulator is a port of gpSP and isn't perfect, but reportedly works fairly well. Unfortunately none of the sites I've seen have bothered to do any extensive testing with GBA homebrew.
The upcoming Supercard DS:TWO (release date unknown) will reportedly contain the iPlayer internals, so it will also be compatible with this same GBA emulator. They're also reporting that there will be an SNES emulator on the DS:TWO as well, but there has been no information about that. I'm hoping it's an entirely new emulator built for the upgraded hardware rather than simply integrating SNEmulDS or something like that.
#172086 - Sektor - Thu Jan 14, 2010 6:37 am
The only slot-1 flashcard that can run a GBA emulator is the iPlayer. It won't work on any other flashcard since it requires the extra power the iPlayer offers.
_________________
GTAMP.com/DS
Last edited by Sektor on Thu Jan 14, 2010 6:40 am; edited 1 time in total
#172087 - dantheman - Thu Jan 14, 2010 6:39 am
| Sektor wrote: |
| The only slot-1 flashcard that can run GBA emulator is the iTouchDS. This is because it contains a faster CPU than the DS. |
Careful, the iTouch is an entirely separate, regular old slot-1 device (I think made by the M3 Team but I'm not positive). It's the iPlayer that has the faster CPU. Easy mistake to make though, I'll admit.
EDIT: Heh, you fixed it before I posted the message. Ah well.
#172088 - Sektor - Thu Jan 14, 2010 6:41 am
Yeah you caught me. I wouldn't have even made my post if I saw yours.
_________________
GTAMP.com/DS
#172089 - cantab - Thu Jan 14, 2010 6:50 am
Of course I meant homebrew ROMs. .gba files. Whatever they're called.
What are the technical reasons for the DS being unable to run GBA software from slot 1?
#172090 - elwing - Thu Jan 14, 2010 7:18 am
I'm totally unsure, but if memory serve it's just 'cause the DS, when running in GBA mode can't access the slot1 device... the Iplayer, don't run in GBA mode, the Iplayer cointain a processor and it EMULATE the GBA...
#172092 - kusma - Thu Jan 14, 2010 10:08 am
| cantab wrote: |
Of course I meant homebrew ROMs. .gba files. Whatever they're called.
What are the technical reasons for the DS being unable to run GBA software from slot 1? |
The main reason is that the slot-2 provides 32 megabytes of memory-mapped ROM, whereas the slot-1 is not memory-mapped.
#172101 - dantheman - Fri Jan 15, 2010 12:49 am
Right, the memory mapping is a major issue. The GBA works by directly executing instructions off the ROM chip, which has lightning-fast read access. DS cartridges are block devices and load chunks of ROM into RAM before execution. This works fine for DS games, which are programmed to work that way, but emulating GBA games that expect that lightning-fast response would be difficult, especially for larger file sizes. There's also the question of whether or not the DS has enough horsepower to emulate the GBA on its own, which is debatable at best.
Also consider that the ARM7 functions entirely differently in DS mode than it does in GBA mode, so it's not like you can just send everything to the ARM7 and be done with it.
If you're asking why we don't just run the GBA file in GBA mode but storing the game on slot-1, it's because the instant you enter GBA mode, everything DS-specific gets disabled and any RAM gets cleared (minus a small portion of VRAM where you can place a border in the dead space around the GBA frame if you'd like). In other words, in GBA mode the system has no idea slot-1 even exists, let alone how to access it or stream data from it dynamically. Thus, in order for slot-1 to be used at all, it would have to be some sort of software emulator running in DS mode, which in essence is what the GBA emulator for the iPlayer is. The difference is that the iPlayer has the extra hardware that is multiple times more powerful than the components on the DS(i) itself, so it can manage the emulation without too much slowdown.
Really, your best option is to get some sort of slot-2 device, which will run the GBA files natively in the DS's GBA mode, no software emulation needed at all. If you've got a DSi, your only option at the moment is the iPlayer.
#172105 - sonny_jim - Fri Jan 15, 2010 4:57 pm
That's a great answer, dan!
_________________
| Quote: |
Would that be the internet driver for the program?
|