Where to put BIOS files? Need help understanding


I installed retroarch on my FireTV and I have a question about how use use the BIOS files.

The settings point the system/BIOS folder to /data/user/0/com.retroarch

However, I can’t seem to find this directory using ES file explorer. So while I have the .bin files I am not sure what to do now.

What happens if I change the system/bios directory? Does it break other emulators? If I change it and then download CORES is that effective?


You can make any user-readable directory your system/BIOS directory. RetroArch doesn’t come with any BIOS images, so if you haven’t put anything in there, you can’t break anything by changing it.


a newbie question with BIOS, why should I use BIOS files in the first place?

In the past I know some emulator wouldn’t work without a working bios. However I see RetroArch works fine without any. (it tells me bios missing but that’s about it.)

so what is the point of putting proper BIOS in place? Performance boost or some hidden traits?


Some emulators require bios, some don’t, some work both way (bios becomes optional because it can be emulated), it is highly recommended to use bios even when it is optional.


Thanks! Now it makes so much sense to me!


Sorry to bother you again. I put a proper bios for GBA last night (with MD5 checks out according to docs). Enabled loading bios if found. Could see boot screen as well.

Everything seems great right? That is until I tried to load states.

I have multiple saved states for Fire Emblem. No matter which one I choose, it takes me right back to the boot screen.

Frustrated and couldn’t figure out why. Is this the expected behavior as I used the BIOS after playing the game? Anything I can do to bring back my saved states?

Oh forgot to mention I’m using Android, RetroArch64 version from Google Play Store.


Where did the states come from? Same core, same RetroArch?


Yep, everything else remained exactly the same as before. The only difference was adding the gba_bios.bin to the ‘system’ folder.


Well, the easiest thing to check would be to remove the BIOS and try to load the state again. It is possible that the presence of a BIOS could break it, as states are extremely volatile. They are snapshots of the emulator at that point in time and they can be broken by even very small changes to anything that affects that emu state.


Good point! I’ll give it a shot and report back.


Removing the BIOS indeed revived my saved states! Guess I’ll only put BIOS in place after beating Fire Emblem then. Hope it doesn’t take too long this time… (could never finish it before :joy:)

Edit: stupid me. I just realized I can use the Suspend feature of the game, turn each of my saved stated to a Suspend save while BIOS gone, resume from the Suspend with BIOS in and save it as a new state. It would take a bit of back and forth tinkering but I don’t need to worry about losing saved states any more.