Install on BananaOS

BananaOS is a light Linux made only for the RG DS and RG DS Plus. GBA DS runs on it as a port, from the same zip as on ROCKNIX. Support is new: report anything that doesn't work (see Troubleshooting).

Install

1. Download the latest gba-ds-v…-linux-aarch64.zip from the Releases page.
2. Unzip it into the card's roms/ports folder (on the device: /data/roms/ports). You get a gba-ds/ folder, a GBA DS.sh entry and images/. Banana's file sharing (Settings → Network) lets you copy it over Wi-Fi.
3. Keep your Game Boy Advance games in roms/gba (/data/roms/gba), where Banana's own GBA list finds them too.
4. In Banana's menu, open Ports and start GBA DS.

How it fits in

• Both screens: Banana has no compositor, so GBA DS opens a window on each panel and draws them with the GPU, straight onto the panels (SDL's KMS/DRM driver); touches on the bottom panel work as on ROCKNIX. Banana's ports launcher normally switches the bottom panel off; GBA DS switches it back on while it runs.
• Buttons: the zip has a mapping for the RG DS's built-in controls (gba-ds/gamecontrollerdb.txt, ROCKNIX's), since Banana ships none for SDL apps. The buttons work as on ROCKNIX (HOME, or a tap on the bottom touchscreen, opens the pause menu).
• Where things go: these replace ROCKNIX's paths unless you've changed them in gba-ds.cfg:

Games	/data/roms/gba
Battery saves (.sav)	/data/saves, beside RetroArch's: a game's RetroArch save (.srm, from Banana's gpSP) is carried over the first time you start it in GBA DS
Screenshots	/data/screenshots
Cheats	roms/ports/gba-ds/cheats (RetroArch .cht files; subfolders are fine), and RetroArch's /data/retroarch/cheats
Save states, settings from the menu, logos	roms/ports/gba-ds/states/
Log	roms/ports/gba-ds/gba-ds.log

• RetroAchievements: the account from Banana's first-time setup (banana/accounts.conf) is used, in casual mode. Banana has no curl program, so GBA DS talks to the server through Banana's curl library instead (the log says "using libcurl").
• Battery and clock in the pause menu come from the system, as on ROCKNIX.
• Back to Banana: closing GBA DS from Ports goes back to Banana's menu.

Starting games from Banana's Game Boy Advance list

GBA DS can take over the second-screen games in Banana's own Game Boy Advance list, so you don't have to open GBA DS first:

1. Start GBA DS from Ports, open Settings in its game list (tap it, top right, or press SELECT) and switch GBA DS in BananaOS's GBA list on.
2. Restart BananaOS (Settings → System), since Banana reads its systems list when it starts.

Then a game picked in Banana's Game Boy Advance list starts in GBA DS when GBA DS has second-screen support for it (see Supported games), and closing it goes back to Banana's menu. Every other game plays in RetroArch (gpSP) as before.

How it works: Banana reads its systems from banana/systems.conf on the card when there is one, instead of its built-in list. Switching this on makes that copy (or edits yours) so the Game Boy Advance entry runs gba-ds/banana-play.sh, keeping the original line as a comment (# gba-ds: run = ...), which banana-play.sh uses for the games GBA DS doesn't support. Switching it off puts the line back, and deletes the copy if GBA DS made it and nothing else in it changed.

While the copy is there, systems added by later BananaOS updates don't appear in Banana's menu until you switch this off (Banana's own list is always in banana/systems.conf.default, to compare). If GBA DS's folder moves, it updates the line the next time it starts.

If something's wrong

Send roms/ports/gba-ds/gba-ds.log (and for a stutter or slowness, a log made with export GBADS_DEBUG=1 added near the top of gba-ds/launch.sh). The log's first lines say it found BananaOS, which paths it used, the window size and the frame pacing.

To compare other ways of reaching the panels, add a line near the top of gba-ds/launch.sh (before if [ -d /etc/banana ]):

• export GBADS_BANANA_VIDEO=evdev: one window over both panels drawn by the CPU, copied onto them each frame (24-30 frames a second on an RG DS Plus).
• export GBADS_BANANA_VIDEO=offscreen: the same drawn with OpenGL ES and read back (under 5 frames a second).