Homebrew Is it possible to have DS games boot straight from home menu?

[Absestos]

I have my 3DS setup with TwilightMenu to load DS dumps from my MicroSD, and after seeing how Ultimate injector allows generating CIAs that behave 100% like native 3DS apps (install via FBI, launch via tile on home screen, uninstall via settings/data management), I am wondering if it would be possible to somehow do the same for DS dumps.

A it is TwilightMenu can be invoked from the main menu via the CIA, but my understanding is that it's not a standard app since
- It causes the 3DS to reboot in DS mode
- Makes it run the BOOT.nds file from the root of the microSD
- That code eventually loads TwilightMenu

But still, would it not be possible to generate CIAs for DS games? One could:

- Pack the nds dump itself as part of the CIA archive
- On install, the nds dump gets extracted to the SD
- When launching the installed CIA some code writes a small config file to a known location in the SD, with the path of the dump file to run
- BOOT.nds could read the config file and run the dump

As for why one would want to do this, I think it would be nicer to have all one's games in the main menu

 

[Shadow#1]

I have my 3DS setup with TwilightMenu to load DS dumps from my MicroSD, and after seeing how Ultimate injector allows generating CIAs that behave 100% like native 3DS apps (install via FBI, launch via tile on home screen, uninstall via settings/data management), I am wondering if it would be possible to somehow do the same for DS dumps.

A it is TwilightMenu can be invoked from the main menu via the CIA, but my understanding is that it's not a standard app since
- It causes the 3DS to reboot in DS mode
- Makes it run the BOOT.nds file from the root of the microSD
- That code eventually loads TwilightMenu

But still, would it not be possible to generate CIAs for DS games? One could:

- Pack the nds dump itself as part of the CIA archive
- On install, the nds dump gets extracted to the SD
- When launching the installed CIA some code writes a small config file to a known location in the SD, with the path of the dump file to run
- BOOT.nds could read the config file and run the dump

As for why one would want to do this, I think it would be nicer to have all one's games in the main menu

Not possible

 

[RickFryMcFly]

I always recommend getting a good quality flash cart for regular DS games.

 

[Shadow#1]

I always recommend getting a good quality flash cart for regular DS games.

They all scoff at thst idea

 

[RickFryMcFly]

They all scoff at thst idea

I get it, they cost money and you have to wait for them to come over on the slow boat from China usually but I think it's worth it. The games boot and run as good as the original cartridges

 

[Shadow#1]

I get it, they cost money and you have to wait for them to come over on the slow boat from China usually but I think it's worth it. The games boot and run as good as the original cartridges

I know right

 

[RickFryMcFly]

I have my 3DS setup with TwilightMenu to load DS dumps from my MicroSD, and after seeing how Ultimate injector allows generating CIAs that behave 100% like native 3DS apps (install via FBI, launch via tile on home screen, uninstall via settings/data management), I am wondering if it would be possible to somehow do the same for DS dumps.

A it is TwilightMenu can be invoked from the main menu via the CIA, but my understanding is that it's not a standard app since
- It causes the 3DS to reboot in DS mode
- Makes it run the BOOT.nds file from the root of the microSD
- That code eventually loads TwilightMenu

But still, would it not be possible to generate CIAs for DS games? One could:

- Pack the nds dump itself as part of the CIA archive
- On install, the nds dump gets extracted to the SD
- When launching the installed CIA some code writes a small config file to a known location in the SD, with the path of the dump file to run
- BOOT.nds could read the config file and run the dump

As for why one would want to do this, I think it would be nicer to have all one's games in the main menu

Just make sure if you do go the flash cart route, to get one without a time bomb. I have the R4I gold and it works great.

 

[Vulpes-Vulpeos]

to get one without a time bomb.

It's not a problem, as you can always install YSmenu.
For me, there is one problem with my flashcard (R4i-RDHC RTS) - battery drain in standby. If I leave it in my N2DS XL, it will drain it after 5-6 hours

 

[Viri]

You can, I got mine to load from the Home menu, I forgot how I did it. I think it was with a forwarder.

 

[CeeDee]

I think what you're looking for is probably a DS forwarder, something like this.

 

[godreborn]

yes, there are ds forwarders. the twl nand is limited though as you can install a max of 40. I'm not sure, but I think you might need a flash cart for that, since it asks which flash cart you're using. there's a java app that will create them for you. it's on the board somewhere.

 

[Deleted User]

yes, there are ds forwarders. the twl nand is limited though as you can install a max of 40. I'm not sure, but I think you might need a flash cart for that, since it asks which flash cart you're using. there's a java app that will create them for you. it's on the board somewhere.

You don’t need a flash cart to use forwarders

 

[Deleted member 42501]

I always recommend getting a good quality flash cart for regular DS games.

Why? The menu apparently does all the job with none of the downsides like battery drain that all flashcarts provide so whats your reasoning?

 

[godreborn]

some games don't work. golden sun for the ds for example unless using a flash cart. twilight menu++ will tell you if a game is incompatible, so it must have some sort of whitelist.

 

[Absestos]

Forwarders are closer to what I had in mind and a definite step up in usability, but I am curious: *why* do some games only work via flashcards, technically?

And also, would it technically be possible to create a forwarder that includes the nds rom? Like what happens with Virtual Console injector.

I'm not complaining about the status quo or asking that my idea to be taken up and worked on, just curious about the tech.

 

[Ryccardo]

*why* do some games only work via flashcards, technically?

A flashcard, ideally, accurately emulates an original game card (this is the case for the orange sky3ds, for example) and so is functionally 100% the same as the original

Most if not all DS flashcards are not exactly that way, in part because they expand on that concept (like DLDI), in part because many of them do apply patches to original game backups (save types, support for excessively slow storage, etc) but still the good flashcard & kernel combos, like Wood and whatever the DSTwo uses, achieve remarkable accuracy and excellent compatibility at simulating original DS cards;

with DS-mode software virtualization, as is the case with nds-bootstrap (or with any other DS-mode addon for a DS title, such as a cheat engine or debugger), first and foremost you have this added software (which consumes memory and processing power) that is there and the game developers did not account for, so perfect compatibility is not even necessarily possible in theory, while accuracy is obviously much lower since it has to apply major mods to make slot-1 reads point to a file on SD (which in turn requires more code to be accessed)

tldr - nds-bootstrap is more invasive, with respect to the game's operation, than any slot-1 flashcard

would it technically be possible to create a forwarder that includes the nds rom?

Probably yes, but 1- there is a size limit for DSiWare, 2- the capacity of twlnand would be too low for more than a few games (or 0 games depending on the exact titles), 3- why the hell are you playing DS/i titles on a disgusting 3DS screen anyway?!

 

[Absestos]

A flashcard, ideally, accurately emulates an original game card (this is the case for the orange sky3ds, for example) and so is functionally 100% the same as the original

Most if not all DS flashcards are not exactly that way, in part because they expand on that concept (like DLDI), in part because many of them do apply patches to original game backups (save types, support for excessively slow storage, etc) but still the good flashcard & kernel combos, like Wood and whatever the DSTwo uses, achieve remarkable accuracy and excellent compatibility at simulating original DS cards;

with DS-mode software virtualization, as is the case with nds-bootstrap (or with any other DS-mode addon for a DS title, such as a cheat engine or debugger), first and foremost you have this added software (which consumes memory and processing power) that is there and the game developers did not account for, so perfect compatibility is not even necessarily possible in theory, while accuracy is obviously much lower since it has to apply major mods to make slot-1 reads point to a file on SD (which in turn requires more code to be accessed)

tldr - nds-bootstrap is more invasive, with respect to the game's operation, than any slot-1 flashcard


Probably yes, but 1- there is a size limit for DSiWare, 2- the capacity of twlnand would be too low for more than a few games (or 0 games depending on the exact titles), 3- why the hell are you playing DS/i titles on a disgusting 3DS screen anyway?!

Thank you so much for writing that! My Google skills seem to fail me when it comes to finding these kind of technical details (if I'm lucky I end up on some other GBAtemp thread where people go more in depth than usual - otherwise noise).

Three questions more if I may:

- Why would twlnand size be an issue when twilight menu loads the rom from the SD card?
- You say "make slot 1 reads" as if the games were doing fopen() and similar... is that what happens? I always thought those carts were like GB/GBA - just a big chunk of data to be memory mapped
- The 3DS screen is bad sure, but isn't it still better than the original DS's?

 

[RocketRobz]

Thank you so much for writing that! My Google skills seem to fail me when it comes to finding these kind of technical details (if I'm lucky I end up on some other GBAtemp thread where people go more in depth than usual - otherwise noise).

Three questions more if I may:

- Why would twlnand size be an issue when twilight menu loads the rom from the SD card?
- You say "make slot 1 reads" as if the games were doing fopen() and similar... is that what happens? I always thought those carts were like GB/GBA - just a big chunk of data to be memory mapped
- The 3DS screen is bad sure, but isn't it still better than the original DS's?

1. That's only if you want the ROM on TWLNAND itself.
2. Yes, that's true. Maximum ROM size is 512MB.
3. Yes, only if you want to use widescreen.

 

[Vulpes-Vulpeos]

@Robz8 is it possible to do this?

And also, would it technically be possible to create a forwarder that includes the nds rom? Like what happens with Virtual Console injector.

It will be great to have such "injects".

Or, at least, is it possible to create barebone version of TWLmenu++ for 3ds? Only 1 theme (DSi menu theme), no splashes, no emulators, no ap cheats, no widescreen. Nothing, except ds games.

 

[RocketRobz]

@Robz8 is it possible to do this?

It will be great to have such "injects".

Maybe with DS ROMs around 4MB, but with no saving.
For big ROMs, we'd have to fix the current 3DS TWLNAND init code in GodMode9i first, so that we can read the TWLNAND contents.
For saving, it would still have to be done on the SD card, as writing to TWLNAND in DSi mode is unsafe.

Or, at least, is it possible to create barebone version of TWLmenu++ for 3ds? Only 1 theme (DSi menu theme), no splashes, no emulators, no ap cheats, no widescreen. Nothing, except ds games.

That's possible, but it's currently exclusive to nightlies to make updating faster when testing nightly builds.