SIDOU (emulated)
A…' play C4–F5 Z X octave 1 6581 / 8580 7 menu , . or drag / scroll K1–K4: cutoff, resonance, the sound's own control, release drag / scroll PRESETS: the preset
What this is
SIDOU is free firmware that turns the M-VAVE FM-1 pocket synth into a Commodore 64 SID
instrument: an emulated SID chip (6581 or 8580) played from the FM-1's keys and knobs and over MIDI,
with three effect slots after the chip. It also plays and edits GoatTracker 2 songs with a step
sequencer and a tracker (0 SEQ, Space PLAY). .sid playback is planned.
This page runs the newest build of SIDOU's main branch, rebuilt whenever the firmware or this page changes, so it can be ahead of the latest release; the build line under the player names it (run locally: your own build) in fm1-emu,
an emulator of the FM-1's chip, in WebAssembly: the same update package (sidou.fwsc) a
real FM-1 would take. SIDOU runs on a real FM-1 too: see the
latest release for installing it.
Build: loading…
Own an FM-1? Send the showcase songs to it over USB, from this browser (Chrome or Edge).
Turn a song into a MIDI file: any GoatTracker 2 song, one MIDI channel a SID voice, made in the browser.
The how-to videos: seventeen short ones, from the first sound to MIDI learn.
How to play
Press Start (a browser plays sound only after a click). Any key skips the boot.
The first-run tour. After the boot, SIDOU shows three large messages, one after another: TURN K1 (turn , ., or drag or scroll over the K1 knob), PRESS ENV (press 3, or click the ENV button) and HOLD HOME FOR HELP (hold 7, or hold the mouse on HOME, for a moment: a help card opens, and any control closes it). Each goes when you do what it asks, or after 8 seconds. On a real FM-1 the tour runs once, after an install, because the unit remembers it in its flash. This page keeps the emulated flash in your browser, one save per SIDOU build: the tour and the full boot come once per build, and what you save (settings, songs) is there on your next visit. Export… writes it to a file and Import… brings it back; More… → Reset saved flash starts over. Clearing the site's data in the browser removes it.
| A W S … ; ' | the note keys, C4 to F5 (a piano row: W E T Y U O P are the sharps) |
| Z X | OCT− / OCT+ |
| 1 | FX: the chip, 6581 or 8580 |
| , . | K1 down / up (the cutoff on LIVE) |
| K1 K2 K3 K4 | drag up / down or scroll over a knob. On LIVE: cutoff, resonance, the sound's own control (pulse width, decay or sync ratio, by the sound) and the release. They show the page SELECT chose (TONE, or a slot's Amount, A, B, Mix); on the CHIP view (menu → CHIP) the focused section's controls |
| PRESETS | the big knob: drag or scroll for the next or previous preset (SAW LEAD, PWM BASS, SYNC LEAD, NOISE PERC, then DICE, which rolls a new sound each turn) |
| 5 held + K1–K4 | EDIT: the selected effect slot's Amount, A, B, Mix |
| 2 SCL | selects the next effect slot (Distortion, Modulation, FX) |
| 3 ENV | the selected slot's next algorithm, which sounds at once |
| 7 HOME | a tap: the menu from LIVE, back one view elsewhere; hold it for 0.6 s: the help card of the view, for what it is doing (SELECT turns a two-page card) |
| ← → | SELECT: pages the knob row on LIVE, moves in the menu and on CHIP |
| ↑ ↓ | ALGORITHM: the chip's profile on LIVE (or a slot's algorithm); in the menu, changes the item's value |
| 8 SAVE | in the menu: opens the highlighted item (CHIP, TRACKER, SETTINGS, SONG …); in a song view: saves the song; held while you turn a knob: MIDI learn |
| 0 SEQ | the song views, back to the one you used last; again: STEP, TRACKER, ORDER, INSTR, TABLE, round |
| Space PLAY / R REC | plays SIDOU's song (SIDOU LOOP) and stops it / record mode |
| MASTER | volume (drag the knob at the top left) |
| Menu → SETTINGS | KEYS, SOUNDS, ROWS, CARDS, STORE, THEME, REC: they save themselves |
The mouse or a touch screen plays the panel directly (4 LFO, 6 GLO and 9 ARP are the other buttons). All controls: docs/reference/controls.md.
MIDI in: pick a keyboard under MIDI in (Chrome, Edge, Firefox; Safari has no Web MIDI). SIDOU plays notes on every channel; CC 74 cutoff, 71 resonance, 1 pulse width, 7 volume, program change 0–3 the presets (MIDI map).
The emulator's limits
- No USB. fm1-emu has no USB device, so no USB-MIDI in or out: MIDI from this page reaches SIDOU through the emulated TRS MIDI IN jack, and the panel's MIDI out goes nowhere.
- No watchdog. The power and reset block's registers (P33) keep what SIDOU writes, but nothing acts on them, so a hang is not reset as it would be on the chip.
- Instructions, not cycles. The emulator counts instructions; the clock setting is instructions per second. A real FM-1's timing can differ. The page starts at 240 MHz, the clock SIDOU's audio budget is checked at. If the status line's count of short audio quanta keeps climbing, your computer is behind: pick a lower clock (SIDOU may then run short of time itself, heavy effects first).
Credits
The emulator and this page's player (main.js, the audio worklet, the wasm) are
fm1-emu by Joakim Eriksson, under the
MIT licence, unchanged but for two lines
(web/patch-main.sh).
SIDOU's firmware image is GPL-3.0-only (text); the package carries three files of JieLi's AC79 SDK under Apache-2.0 (text). Everyone SIDOU builds on: CREDITS.md.
SIDOU is an independent project, not affiliated with M-VAVE or Commodore trademark holders.