with luma ntr hans etc you can redirect the rom of the game from the sd card for mods but in ds mode you can't run retial games off the sd yet except for demos and maybe dsiware roms
Because the DS doesn't have an SD card slot Not writing a long answer because this guy will still argue with me.
Several reasons: 3DS roms are intended to be run from multiple locations. Cartridge or eShop, and possibly Virtual Console in the future. So, they call system APIs, which we can replace. DS roms though don't have system APIs, they interact directly with bare hardware to read the cartridge slot. When running in DS mode, the SD card is turned off, and we don't yet know how to turn it back on. (not the case for DSiWare)
well still ds emulators on the pc can load a nds rom off the sd slot in the pc only problem with those is my pcs cpu isn't real good so its laggy playable but laggy
ncch's were designed to be versatile while srls weren't. You can run an ncch from different media by just flipping a few flags while and srl has to be recompiled to do the same thing. that's a simple non-technical answer. no reason to go into any more detail so don't ask.
The 3DS has dsi hardware in it to run games natively. THe dsi hardware shuts off the sd card slot as MikeMK said. On your pc, you are recreating the hardware in emulation, and your pc's sd slot (or any storage location for that matter) can be used to emulate a cartridge slot. So on your pc, the "ds" think that your rom file is a cartridge.
ROM, Read Only Memory. ROMS, a fancy name for dumped ROMs from cartridgaes etc. Only way for a DS system to be able to have a SD Card is through a expantion card (most called them flashcards) ds filesystem isn't the same as the 3ds filesystem. It's like comparing FAT and FAT32. They aren't the same but share the same name.
nds expects (at least commercial game) data to be pushed to and read from slot1. That's basically all the more there is to it. The problem is effectively emulating the card read from within nds mode (or somehow redirecting it to a device that the system isn't expecting to be there, which from my understanding they've made some really good progress in this area).
As soon as you boot a nds rom that is retail, the sd card slot is disabled and it can't read the rom. That simple. Edit: I didn't click post so It just posted, (sorta 'd?)
