Before anyone say or stick that image of R4 don't run GBA games, listen (read lol) what my question is. Maybe could be relevant, maybe not.
[Guide] DS/DSi/3DS Flashcards + GBA
As promised, I delivered, welcome to the ds flashcard noob tutorial !Breviaire des echecs tartakover pdf.
Keep in mind english is not my native language, but please point out any mistake I may have made.
Without further ado, let's get started !
What are flashcards ?
Flashcards allows you, among other things to play DS roms from a cartridge. They often come with a slot for you to put a microsd card in, to store your games.
Which DS is this tutorial for ?
All flashcards can be used on original DS and DS lite.
Some of them can also be used on DSi to play DS games, or sometimes DSi games too.
If you have a hacked 3DS with AL9H/Luma installed (the state of your 3DS after having followed the guide), you can use flashcards with your 3DS to play DS games. Launching DS games from SD card is highly experimental for the moment and does NOT WORK WELL. So the only way to play DS games on the 3DS is to use a flashcard.
Also take note that while some flashcards such as Gateway and Sky3DS allows you to play 3DS games from a flashcard, they are really expensive, and you can achieve the same results (and even more) by simply hacking your 3DS by following the guide (3ds.guide).
Is it expensive ?
Luckily, those are really cheap. It also depends on the features you want out of your flashcard.
Okay so which one should I get ?
Again, it depends on what you want out of it.
I want to play DS games on my old DS (DS Fat or DS Lite)
You can use your old original R4 if you have one. However, it does not support High capacity SD cards. You can only use SD cards with a capacity less than 2GB (which is enough for around 15 DS games).
If you want to buy a flashcard, I recommend the DSTT. It has nearly full comaptibility with all DS titles and is really cheap. It also supports SDHC (Up to 32GB capacity). The website I linked is safe, and also I recommend not to buy the SD card via this website, you should buy one off amazon, it will probably be cheaper.
But I also want to play GBA games on my DS Fat/DS Lite !
In this case, you have two options.
You can buy the more expensive Supercard DSTWO. This is one of the only cards which can run GBA games. But one of the drawbacks is that it uses more battery. It also has perfect compatibility with both the DS and DSiWare titles.
You can also buy a slot two flash card (It goes in the GBA port). Currently, only two are still manufactured : EZ-FLASH IV and EZ-Flash 3in1. Fortunately, they have perfect compatibility.
Also, as said by /u/el_wonso
If you want GBA games on DS lite you should also consider other slot 2 carts (used) as 3in1 is quite expensive. I've bought M3 GBA Expansion Pack for ~10 dollars some time ago and it works great with my R4. You will need M3DS Real (slot 1 cart) or GBA ExpLoader (homebrew) for this.
I don't have either of these myself, so if you need a tutorial to setup them, I suggest you to check this tutorial from GBA Temp.
Okay, but I have a DSi, what do I do?
Just buy a DSi compatible flashcard, the Supercard DSTWO is compatible, and on the cheaper side of things, the R4i Gold is also an option, though I am not sure if it can play the DSi games, which consists of five games (You don't really miss much honestly).
Again, if you also want to play GBA games on your DSi. The DSTWO is your only option, given the fact that the DSi lacks the slot-2 port.
What if I have a 2ds/O3ds(XL)/N3ds(XL)
You should first follow the guide I linked before, I'm so kind I am linking it again for you.
Once you are done with the guide, you should have AH9L and Luma3DS installed. Luma is a CFW that allow you to use any (most) flashcards made for the DS or DSi on your 3DS !
You really have two options for the flashcard to get. You can get the DSTT or the Supercard DSTWO if you want perfect compatibility.
This time around, the GBA feature of the DSTWO is not as useful as for the other games, since you can download an emulator to launch with the homebrew launcher to run the GBA games.
You also inject custom virtual consoles using the software developped by nintendo to emulate GBA. But it's not the goal of this tutorial, so if you want to, there is a good tutorial here.
Now I have a flashcard, what's next ?
First you should not forget to buy a microSD card for your flashcard, typically under 32GB, and under 2GB if you are using the original R4 or M3 Simply. They are pretty cheap on amazon (under 15€).
Now that you have the flashcard, we shall download the firmware for it :
Once you have the firmware for your flashcard, you should now connect your sd card to you computer and proceed to format it. I like using this tool. Format your sdcard to FAT 32, this is really important.
Now that your sd card is formated, if you are using the firmware for R4/DSTT/M3, just copy the folder _rpg and the file _DS_MENU.DAT to the root of your SD card. You can then proceed to create a folder that you can name 'Games' or 'Homebrews', and you will put your .nds files in the folder, or anywhere in your sd card really. Keep in mind that the flashcard will create .sav files for each .nds game. So if you want to keep the save and use it on a emulator for instance, this is the file to look for.
Now for DSTWO, it is even simpler ! Just copy the dstwoupdate.dat file to the root of your microsd card, and that's it ! Same here, you might want to create a folder for your .nds games. That's pretty much it ! If you have any question, don't hesitate to ask ! Also if you want a more in-depth guide on how to customize your DSTWO (and use emulators for GBA and SNES), I suggest reading through this.
Where to get the games from ?
Gba Exploader Rumble
This link is pretty much the ultimate solution, I believe it has all the available DS roms. If you need to find the ID for a game, you can find it on this site : http://datomatic.no-intro.org/index.php?page=search
You can also use this : https://goo.gl/yJE7sa
You may also want to forward DS games (that will boot on the flashcard) directly to the home menu. You can do that by following this guide.
Gba Exploader R4
If you want to run your games faster (still from the flashcard), you may want to use TWloader. Guide here