If you got an Ak2/i with AKAIO, you can use the built in 3in1/FAS functions to write to the F2A. It works with the F2A 256M.

If your save doesn't stay on the F2A after a reboot, it means the battery is dead and you will have to replace the battery.

 

ExpLoader doesn't support the F2A.


There is the standalone loader FAS tool: https://filetrip.net/nds-downloads/applications/download-fas1-1-5-f1650.html

you want to probably use this if you don't have or plan to find a AK2/i.


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@migles
I'll get around to it, eventually.

 

Exploader can erases the boot sector of a EZIV, it is fixable but requires the use of a EZ writer/reader from a EZ2 or EZ3.

There are only a handful of stand alone loaders, most of them stopped development before the 3in1+ came out.
I don't remember if Cory's loader did or didn't support the use of a frame.
CycloDS didn't use a frame, if it did I don't remember it.
NDStation, didn't have frames from what I remember. Frames were new when the v1.2.1 was released. here
Every R4 clone basically relied on wood for 3in1 support, all the R4 clones that used the older system files didn't have 3in1 support and had to use an external loader.
YSMenu probably had frame support.
M3 basically didn't use frames for their gba expansion pack, even in the M3i zero.

 

Using that tool gives me
'detecting flash type: unknown
***exception unsupported flashcart (0xff)'
I wonder if my cart is broken. I don't have an AK2/i.
Oddly, this appears to be the homebrew ROM on the cartridge right now. http://pdroms.de/files/gameboyadvance/apydia-release-2

 

Mine is a card like this: http://livedoor.blogimg.jp/izumififty/imgs/7/3/7340b86e.jpg

 

You should have been able to use the FAS1 with that version.

 

It doesn't necessarily mean it is a lemon. It might be mean you have a hardware version that isn't supported by FAS1, in that case you would have to get the cable or reader/writer to use the F2A.