Manual

BOP-1 turns the M-VAVE FM-1 into a music toy for children that is also a real synthesizer. Switch it on and music plays. Nothing a child can press sounds wrong, and every knob changes something they can see: a friend whose body is the sound. The same toy grows with the child, through four doors: Play (age 3 and up: press things), Make (6 to 8: beats, loops, songs), Lab (9 to 12 and up: a real subtractive synth with its real names, and lessons) and Games. This manual is for the grown-ups; the children need none of it.

1Install

Try it first: the browser emulator runs the same code with sound, played with the mouse, a touch screen or the keyboard.

Install from the browser: open the web installer in Chrome or Edge, connect the FM-1 with a USB data cable and press Install. Don't unplug it while it's writing; when it finishes, the FM-1 restarts into BOP-1 and plays.

Install from the command line: download bop1-X.Y.Z.fwsc from the latest release, install Python 3 with pip3 install mido python-rtmidi, and from the BOP-1 source run:

python3 tools/fm1_install.py bop1-X.Y.Z.fwsc

Which version: the start screen shows it under the name, and the grown-ups' page at the bottom (About).

Go back: "Back to the stock firmware", at the bottom of the installer page, puts M-VAVE's firmware back (download the FM-1 V15 file from the link there, choose it, press the button). M-VAVE's own updater, M-UPGRADE, works too.

Coming from another firmware: BOP-1 keeps its settings where other firmwares keep theirs, under its own name, and its songs, My Friends and the sticker book in the FM-1's main store (where some firmwares keep samples or patterns). It never reads another firmware's: it starts fresh, and its first save replaces what was kept there.

The stickers: the FM-1's buttons carry synthesizer names (ALGORITHM, ENV, LFO...). For children who don't read yet, print the sticker overlay on sticker paper: a picture for each button and knob (what it does in Play), and the eleven pads for the black keys.

2Getting started

Before you hand it over (two minutes):

1. Turn MASTER (the volume, top left) to the middle.
2. Hold GLO and SAVE together for three seconds: the grown-ups' page opens. For a child of three or four, set Doors shown to Play only (then HOME does nothing and they can't get lost). Check the Volume cap (70 % to start). Press HOME to close it.
3. That's all. Everything else is there to be found.

The first five minutes, together:

1. Switch it on. A song is already playing; the friend in the middle sings along.
2. Press the white keys: the friend sings, and every note fits the song. Press the black keys: drums and funny sounds.
3. Turn the four knobs on the right: the friend changes shape (knob 1), opens its mouth (knob 2, the sound gets brighter), wobbles (knob 3), and the room grows from a bedroom to outer space (knob 4, the echo).
4. Turn ALGORITHM for another friend, PRESETS for another style of music (the place changes), SELECT for slower or faster (a turtle or a rabbit).
5. Press FX: Surprise! A new song. Hold FX and press a white key: a magic trick while it's held.
6. Press REC and play: what you play goes round with the song ("Loop me"). REC again to stop.
7. Hold any button for a second: a card shows what it does.

3The friends

Every sound in BOP-1 is a friend, and the friend's body is the sound. Each control has one meaning, the same in every door:

Sounds made in the Lab and kept as My Friends (up to eight, each with its colour) join them in every door.

4Everywhere

Nothing is deleted with a tap, and no screen can strand anyone: HOME always goes home.

5Play

Ages 3 and up. No reading needed.

The music is already playing when it switches on: a song made by BOP-1 in the style chosen. The friend sings the tune; its band plays along: the bass friend on the left, the sparkle friend on the right, the drums on the floor. When a child plays, the friend's own tune steps aside to let them sing, and the key lights show the song's tune, so they can play along with the lights. The playhead runs dimly across the white keys.

The places: knob 4 takes the friend from a bedroom at night (a little echo) to a cave, a canyon at sunset and outer space (the most).

6Make

Ages 6 to 8. Beats, loops and songs.

A song has four layers, like four friends in a band: Beats (the drums), Bass, Tune (the friend) and Sparkle (arpeggios and chords). It has four parts, A B C D, each one bar long, played in a chain; each part has its own chord, from the song's chords (happy, sad, brave or sleepy). The Bass and the Sparkle follow the chords by themselves, so a line written once fits every part.

Make works on the song Play was playing (switch doors and it's the same song); SAVE keeps it.

The key lights show the steps (the playhead runs through them) and, on Beats, the drum chosen.

7Lab

Ages 9 to 12 and up. The real synth, by its real names.

The Lab's first screen offers the synth (white key 1) or the lessons (white key 2; see 8).

At the top, the signal flow: OSC 1 and OSC 2 into the FILTER, into the AMP, into the FX, with the ENVELOPE and the LFO drawn as wires to what they move. The page open is lit. Under it, a live scope shows the wave at that stage (after the oscillators, after the filter, after the amp), with the stage before it ghosted, so the filter can be seen rounding off a saw. The envelope's page draws its shape, the LFO's its wave. Each knob shows its real name, its value, and the toy's word ("Cutoff / 2.8 kHz / bright").

The Lab lets the resonance ring all the way (a squeal) unless the grown-ups' page says Lab squeals: never; in Play and Make it is always held back.

8Lessons

Behind the Lab door (key 2 on its first screen): ten short lessons, each a few picture cards and a try it the firmware checks. OCT+ goes to the next card (after a try-it, once it's done), OCT− back. Finishing one puts a sticker in the sticker book. The synth stays playable under them.

The printable lesson cards give each one as a classroom activity too, with and without the FM-1, and the real words to learn.

9Games and the sticker book

White keys 1–6 pick a game (the same key again, or PLAY, starts it), 7 the sticker book. PLAY in a game hears it again; HOME leaves. The song stops while the games play, and its sounds come back after.

Each game gives one to three stars (always at least one); every five stars a new sticker. The sticker book holds the eight friends, the eight styles and the ten lessons' stars. Nothing is ever taken away (only the grown-ups' page can reset it).

10The grown-ups' page

Hold GLO and SAVE together for three seconds. SELECT (or ALGORITHM) moves, knob 1 (or PRESETS) changes, HOME closes it and keeps the settings.

11Safety

• The volume cap limits the output, and an always-on limiter keeps it under the cap whatever the MASTER knob, the song or the effects do (a test checks it at every setting, on the heaviest song).
• No squeals: in Play and Make the filter's resonance is held well below self-oscillation and the highest notes are folded down an octave. The Lab can go further unless the grown-ups' page says never.
• A gentle start: the sound fades in at power-on and after a sleep.
• Flashes: whole-screen and whole-panel light flashes are limited to three a second (the WCAG 2.3.1 threshold); with Lights: calm there are none, and no chases. A test measures every scene's brightness frame to frame and fails above the limit.
• Nothing lost by a tap: EDIT is undo; clearing needs EDIT held two seconds, the resets three.
• No reading needed in Play; the picture quick-start and the stickers help the youngest.

12The lights

A rainbow runs across the keys at power-on, after Surprise! and when stars are won (not with Lights: calm).

13MIDI

USB and the TRS MIDI input (with the FM-1's adapter): notes on any channel play the friend; channel 10 plays the pads (General MIDI drum notes: kick 36, snare 38, clap 39, hat 42, tom 45, cowbell 56, and 49, 51, 37, 46, 57 for the funny sounds). MIDI clock in drives the song (MIDI clock: follow), or BOP-1 sends its own (lead). With Keys to USB MIDI on, the notes played go out on the channel chosen.

14Saving

• The song (the one playing and being made) is kept by itself, a few seconds after a change when the music is stopped, and when changing doors; switching off and on comes back to it.
• Eight kept songs: SAVE shows them; a white key keeps the song there. Turn ALGORITHM or PRESETS and the same screen opens one instead (a white key: that song). EDIT undoes an open.
• My Friends (eight sounds) and the sticker book are kept as they change.

Saving to the FM-1's memory takes a moment in which the sound pauses, so BOP-1 saves while the music is stopped, or when asked.

15Troubleshooting

Update mode: hold OCT− and OCT+ together for five seconds. A countdown appears; let go before it ends to cancel.

Calibration: if a button or knob does the wrong thing, hold OCT− and OCT+ while you switch the FM-1 on. The screen then asks you to press each button and turn each knob in turn.

Clicks or dropouts: the most BOP-1 can be asked for is every pad on every step with chords on every step and every effect up. If the FM-1 ever runs short, BOP-1 plays fewer notes at once (the tune first, then the sparkle, then the pads) until it has time again.

After a crash: BOP-1 shows a red CRASH screen and restarts by itself a few seconds later. The next start shows RESTARTED AFTER A CRASH and an address (PC ...) for a moment. If you report the problem, include that address and what was happening.

Safe mode: if BOP-1 crashes twice in a row while starting, it starts in SAFE MODE instead. There's no sound, but USB works, so the web installer can reach it: reinstall BOP-1, or put the stock firmware back from the same page. Press PLAY to try starting BOP-1 normally again. If even safe mode fails twice, the FM-1 drops into the chip's own update mode, and only the rescue below can reach it.

Recovering an FM-1 that won't start

An FM-1 in the chip's own update mode shows a blank screen, and neither the web installer nor M-VAVE's updater can see it. A script in the BOP-1 source puts M-VAVE's firmware back, on a Mac, with the USB cable you already have. In Terminal, from the BOP-1 folder:

bash tools/fm1_rescue.sh

1. If a window asks to install the command line developer tools, click Install. When it has finished, run the line again.
2. If it asks for a password, type your Mac password (nothing shows as you type) and press Return.
3. When it says it's waiting, plug the FM-1 in and switch it on. The script catches it, checks the chip, saves a backup of the FM-1's memory in the fm1-rescue folder in your home folder, and asks before it writes anything.
4. Type yes and press Return. Don't unplug anything until it says it's restarting the FM-1. The FM-1 then starts into its original firmware, and you can install BOP-1 again from there.

The script downloads M-VAVE's FM-1 V15 firmware and JieLi's flash loader, and checks both against known fingerprints. It writes only the firmware area of the memory, never the bootloader or the FM-1's own settings, and checks everything it writes. Running it again is always safe. If the FM-1 never shows up at all, Felucca's FM-1-transporter (a small RP2040 board wired to the USB lines) can still reach it.

16Credits

BOP-1 is free software under the GNU General Public License, version 3. If you share the firmware, you must also share its source code.

• BOP-1 is built on CRT-4 and LCD-4, themselves built on IND-1 and on AMB-1 by Charles Vestal: the engine's frame, the drums, the plate reverb, the screen and knob code, the simulator and the browser emulator.
• The platform (the FM-1's drivers, USB, storage, updates, the installers) is Felucca by Leo Kuroshita (@kurogedelic), Hügelton Instruments, by way of X0X and FoMni.
• Children's synthesizers such as Blipblox inspired BOP-1's ideas (music at power-on, generated melodies, nothing that sounds wrong, lights with the music, a toy that grows into a synth). Only ideas: BOP-1's friends, music, sounds and pictures are its own.
• The games' tunes are traditional or in the public domain.
• The screen's face is Fredoka (SIL Open Font License).
• The idea of running FM-1 firmware in the browser comes from Groove OS.

M-VAVE and FM-1 are trademarks of their owners. BOP-1 is independent: it is not affiliated with M-VAVE.