@arctic flame
3in1 ExpTool is outdated, upgrade to GBA ExpLoader. This is mandatory for the newer revision of the 3in1 as they're not compatible. It also adds a few other nifty features such as compatibility with more carts such as the EWIN Expansion Pack and EZ Flash IV lite Deluxe.
@SHRIVES93
There is no emulator. You use the GBA ExpLoader which is an .nds file to load games from your Fire Card to the 3in1 so that they can run natively on the DS in GBA mode.
You can get the GBA ExpLoader
here.
There are two places that you can load games onto the 3in1: PSRAM and NOR Flash.
Here are the advantages and disadvantages of each:
PSRAM
+ really fast initial load time (10 seconds tops)
- game is lost after power off (must re-load game each time) *
- can only hold up to 128Mbits ROMs (16MBytes)
NOR Flash
+ game is kept after power off (can be used in a GBA/GBA SP/GB Micro/GB Player)
+ can hold full 256Mbit ROMs (32MBytes)
- slow initial load time (up to 5 minutes depending on ROM size)
* save is still kept after power off
Keep in mind that a save for each storage area coexists. So you can have a save for the game in PSRAM and another for the one in NOR Flash at the same time. GBA ExpLoader will ask you to backup your save to your Fire Card each time you run it.