Little update on what's going on
I've been wanting to write this post for a while now, but I'm having trouble focusing on it (as usual, I guess :P ). Regardless, I figured I'd just tell you folks about what's cooking in the melonDS HQ.

The focus for the next release is basically on making melonDS less obtuse to the average user. One of the biggest parts of this is removing the requirement for external BIOS and firmware files.

We started the work in that direction by merging some relevant pull requests, making melonDS able to fall back to the DraStic FreeBIOS and a generated firmware for DS mode. There are still some issues we need to take care of in one way or another, namely:

* We need to either force direct boot, or include some small bootloader inside the replacement BIOS/firmware. The easiest route is to force direct boot.

* The original BIOS includes the Blowfish key required to decrypt the secure area in encrypted ROMs. Lacking the key would make it impossible to support encrypted ROMs, but including it is muddy waters from a legal standpoint.

* A notable exception is that some of the encrypted ROMs, like those found in VC titles, contain the data for Blowfish crypto. It could be possible to make melonDS take advantage of it, but not all ROM dumps out there contain that (it's not normally readable in retail cartridges).

All in all, it seems pretty manageable on the DS side. Things get more rocky on the DSi side:

* As the NUS is still online, it is in theory possible to build a DSi NAND from scratch, though it needs to be studied closer. Some of the contents, like font files, would have to be replicated in free variants. The NAND bootloader would not be terribly difficult to replicate.

* There are several more crypto keys found in the DSi BIOS. While it is still possible to load DSi ROMs without requiring any key from the BIOS (provided the secure area is decrypted, which it generally is), I'm not sure about things like DSiWare.

* There is also the fun part of replicating the DSi BIOS. It has more SWI functions (namely, SHA1 and RSA functions, how fun) and also some fun bugs and shit.

It's nothing insurmontable, but it needs more work.

Another part I'm currently working on is making melonDS's DLDI support less obtuse. For now, DLDI support requires the user to provide a raw SD card image, which isn't very convenient.

Well, you might have read about my latest fatfs adventures. I decided to take this further: basically coding a system that will take a given folder on the host filesystem, create a FAT image from that, and then keep the two in sync. For now, it seems to work reasonably well, but it's going to need some intensive testing before being merged.

There are also some tidbits left: integrating this feature into the UI, making it configurable without being overly complex, ensuring the ROM being loaded is present in the DLDI volume and passing its path to libnds's argv system, adding a read-only mode that will preserve the host folder from any modification, ...

We're working on all these fun features, but it takes time. Especially if you're anything like me, dealing with ADHD (it took me over one hour to write this post). I'm also dealing with some minor real life shito, finalizing details of my transition, social programs to help me find a job adapted to me, etc... nothing bad, though.
Guest says:
Oct 18th 2021
Haven't seen anything run DSi stuff without the bios and it will be interesting if you make it work without them, does using bios, firmware, nand, keys and whatever increase compatibility and fix games or something aside from making things run?
less is more says:
Oct 18th 2021
wow. what wonder.
i love the melon.
by the way,
i need a CAMERA mod. pls. pleeease.
Yours truly, nb Gabi says:
Oct 18th 2021
You're doing groundbreaking stuff, at least for us noob simpletons. You're making a lot of things accessible for gamers and people that love the DS and DSi.

Take your time doing whatever you find is most interesting to do. Of course I could mention you some requests about things that would be great to have, but I see you're doing your best and it's amazing to see a person committed to something they love so much as this. Props for the wonderful job, and big thanks for these posts updating us on how it's all going, they are very interesting to read :D
randomperson says:
Oct 18th 2021
Hello, Arisotura, thanks as always to you and to the rest of the team for your hard work.

As a person dealing with a mental illness as well, I hope you're doing fine.

Noah978 says:
Oct 18th 2021
Wow it only took 1 hour? That’s genuinely impressive, at least compared to me.
Amnesias1000 says:
Oct 19th 2021
I had tried one of the "updates" from Github that added the autouptade option to the dev versions from Github, but then that feature disappeared, I hope it comes back, although it was difficult to make it work with the github key.
akuama says:
Oct 19th 2021
Holy shit, that sounds awesome! PS. how do I know if my roms have this crypto key built-in? I got them all a long time ago, so..
^.^ says:
Oct 19th 2021
"As the NUS is still online, it is in theory possible to build a DSi NAND"
My username says it all ^.^
^.^ says:
Oct 19th 2021
Also what Noah978 said, it would have took me half a day just to write a post like this, don't chastise yourself!
Oh last thing, did you get a chance to take a look at the full DSi bios dump they did some months ago by the way?
Arisotura says:
Oct 19th 2021
randomperson: thanks, I'm feeling good ^^ (I'm tired rn tho)

besides, I like being neuroatypical, it has fun perks too (like the bit where I feel colors in numbers)

akuama: open then in a hex editor, see if the data between 0x1000 and 0x4000 is anything other than all FF or 00

^.^: I was aware the full ARM7 BIOS had been dumped, but didn't hear about anything regarding the ARM9 BIOS. has anything changed since then?
Bob says:
Oct 19th 2021
You are a freaking genius.
poudink says:
Oct 19th 2021
Will this also work with the DSi SD card?
Arisotura says:
Oct 19th 2021
yup :)
Sam says:
Oct 20th 2021
hey, is it possible to add scanline filter in the next update? that woud make my day:)
poudink says:
Oct 20th 2021
Why? The DS has an LCD screen.
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