This is the firmware itself, compiled to WebAssembly from the same sources as the device build: the YM2612 and SN76489 emulation, the tracker and every screen. Songs you save stay in this browser's flash.
| Knobs | Drag up and down, scroll, or focus one and use the arrow keys. MASTER is the volume |
| Keys | Z…/ is F3 to A4 with the black keys on the row above, W…U goes on to G5 |
| PLAY | Space |
| HOME | Pattern view; again for the stage view, with scopes and the YM2612's registers lighting up |
| REC | Edit mode: the keys write notes. KNOB 1–4 edit the note, instrument, volume and effect; FX flips them to the effect columns |
| SEQ · EDIT · GLO | Orders and song settings · the instrument editor and library · songs and setup |
| SEL | Hold it and turn SELECT to mark a block; tap to copy, hold 1 s to paste |
The full control map is in the README. The editor writes songs on a computer keyboard and moves them to an FM-1 over USB; keep this page open and it reaches this emulator's songs too.
Connect the FM-1 with a USB data cable, then let this page use MIDI. Chrome, Edge and Opera on a computer can do this; Safari cannot.
Tested on a real FM-1. It is provided as is, with no warranty of any kind: you install it at your own risk, and the author is not responsible for a bricked or damaged device or lost data (see the GPL-3.0, sections 15 and 16). The update loader is FM1-GM’s: know its recovery steps before you install.