Custom Firmware Portable — Sup M3

| Issue | Likely Cause | Fix | |-------|--------------|-----| | Black screen after booting | SD card not formatted to FAT32 | Re-format using FAT32 with 32KB cluster size | | "No games found" | ROMs in wrong folder or wrong file format | Ensure ROMs are in GAMES/[Console]/ with correct extensions | | CFW installation hangs | Button combination failed | Try holding different buttons (try B + Power or L + Power) | | Save states disappear | Battery died during save | Use only fresh batteries or a fully charged internal battery | | Emulator runs too fast/slow | Incorrect core settings | Press Select + R1 (or L1) during gameplay to open the emulator menu and adjust frame skip |

: Adds low-battery warnings and optimized power profiles. 🛠️ Installation Basics sup m3 custom firmware

The SUP M3 is no longer in production. However, the custom firmware scene remains active, with hobbyist developers occasionally releasing fixes. As of 2025, the latest builds have added support for and WonderSwan emulation. The community is small but dedicated. | Issue | Likely Cause | Fix |

Allowing users to delete the "filler" games that often pad out the 900-in-1 list and replace them with personal libraries via the microSD card. The "Clone" Complication As of 2025, the latest builds have added