Minimal flashcart bootstrap for NDS consoles. Loads /BOOT.NDS and
papers over various device-specific quirks, allowing running 100%
clean homebrew launchers on a variety of such devices.
Copy the contents of the specified directory to the root of your flashcart's memory card:
| Device | Directory | Notes |
|---|---|---|
| Ace3DS+ / Ace3DS X | ace3dsplus | |
| Acekard 2/2i | generic | |
| Datel Games 'n' Music | generic | |
| DSTT | generic | |
| EDGEi | generic | |
| EZ-Flash Parallel | generic | |
| EZ-Flash V | generic | |
| Gateway Blue | gwblue | |
| iTouchDS | m3ds | No bootstub support |
| M3 DS Real | m3ds | No bootstub support |
| R4 (original) | generic | |
| R4 i.L.S. | ace3dsplus | |
| R4/R4i Ultra | r4itt | |
| R4iDSN | r4idsn | |
| R4iSDHC RTS (black) (r4isdhc.com) | m3ds | No bootstub support |
| R4iTT 3DS | r4itt | |
| R4/R4i RTS (r4rts.com) | m3ds | No bootstub support |
| r4dspro.com | r4dspro | |
| r4ids.cn | r4itt | |
| R6 Gold/Silver | mkr6 | |
| Stargate 3DS | stargate | |
| SuperCard DSONE | generic | |
| SuperCard DSONE SDHC | dsonesdhc | |
| Various timebomb carts | generic |
Notes:
- "No bootstub support" means that nds-miniboot does not install its own bootstub, enabling homebrew to return to the boot program on exit. As most people chain nds-miniboot with a menu that adds its own bootstub (like nds-hb-menu), this is not a problem in practice for most users.
Hold START while loading to enable debug output. Note that launching will only continue once you release START.
To build miniboot, the Wonderful toolchain's
wf-tools, toolchain-gcc-arm-none-eabi, as well as BlocksDS 1.7.0+ (for
ndstool and dldipatch) are required. Please follow their respective installation instructions.
.nds files can be loaded essentially anywhere in RAM: in particular,
3.75MB out of the 4MB of main RAM can be used. As such, the easiest
way to load such a file is to put the bootstrap code outside main RAM.
As the fastest place to execute code from is ITCM, I started wondering if one could create a bootstrap that operates entirely from ITCM (32K) and DTCM (16K). That is not a lot of room - the DLDI driver which is provided by a flashcart vendor has to have 16KB of space reserved, leaving only 16KB for the remaining code. Thankfully, there's not much code involved: one needs a lightweight copy of FatFs to read files from the filesystem, a DLDI patcher for the loaded ARM9 binary, and some simple load/reset code on top of that.
I've also never created a freestanding NDS homebrew program before, so I wanted to see what goes into that.
Assorted notes:
arm9.binandarm7.binare extracted from the ELF file as they are position-independent - the binaries relocate themselves upon execution to areas outside of main RAM, they just have to be started from their first word (offset 0).- Initiailization is deliberately sparse; if a given device needs additional cleanup, please document it!
The miniboot source code itself is covered under a mix of two licenses:
- the Zlib license,
- the FatFs license.
Individual binaries for specific flashcarts may be covered under their own respective licenses.