Tetorica FM2612 Playground

pg

• pg is the main playground helper namespace
• pg.play("C4", { channel: CH1, duration: 0.2 }) plays one note
• pg.sleep(0.25) waits in seconds
• pg.liveLoop("bass", async () => {}) keeps a named loop alive
• pg.setBpm(120), await pg.beat(1), await pg.nextBeat(), await pg.tween(1, (t) => {})
• pg.setMasterVolume(1.5), pg.getMasterVolume()
• await pg.livePrepare("main-fx", async ({ fx }) => ...) reuses prepared live state across runs
• pg.scale("Eb2", "majorPentatonic", 2), pg.chord("B2", "minor")
• pg.noteToBlockFnum("C4"), pg.noteLerp("B2", "E3", 0.5), pg.lerp(0, 100, 0.5)
• pg.choose(array), pg.cycle(array), pg.cycle("bass", array)
• pg.rand(), pg.rrange(0.2, 0.8), pg.randInt(0, 7)
• pg.stopLoop(name), pg.stopAllLoops(), pg.stopAll()

fm

• fm is the raw YM2612Synth layer
• await play("C4") plays one note
• pg.fm points to the same YM2612 layer
• fm.setPreset(CH1, pg.presets["one-op-basic"]) applies one preset
• fm.setFrequency(CH1, 4, 553), fm.keyOn(CH1), fm.keyOff(CH1) expose the YM2612 note trigger flow
• fm.write(port, register, value) sends one YM2612 register write
• fm.writeAddress(port, register), fm.writeData(value) follow the YM2612 address/data flow
• fm.read(offset), fm.readStatus(), fm.getIrq() expose low-level chip state where available

psg

• psg is the raw Sega PSG (SN76489-compatible) layer, mixed into the same output as fm
• pg.psg points to the same PSG layer
• pg.psgTone(channel, period, attenuation) writes one PSG tone note helper for channel 0..2
• pg.psgNoise(mode, attenuation) writes one PSG noise helper using raw mode 0..7
• psg.write(value) sends one raw PSG register byte (tone/noise/attenuation, same format as docs/demos/psg.html)
• psg.reset() resets only PSG
• psg.resetAll() resets both PSG and YM2612

fx

• fx is the master FX helper layer
• pg.fx points to the same FX helper layer
• fx.eq(...), fx.filter(...), fx.delay(...), fx.distortion(...), fx.compressor(...), fx.gate(...), fx.wobble(...), fx.flanger(...), fx.reverb(...), fx.slicer(...)
• fx.setChain([filter, delay]) replaces the master FX chain
• eq.bass.set(...), eq.mid.rampTo(...), eq.treble.set(...)
• filter.cutoff.set(...), filter.cutoff.rampTo(...)

Note

This first version already includes a small liveLoop() runtime with shared BPM/beat timing. It is enough to start trying Sonic Pi style loop ideas on top of YM2612, though hot reload and safer live coding behavior still need more work.

Shared Playground URLs may include JavaScript source via ?src=. That source is loaded into the editor and waits for an explicit Run. During execution, common network APIs are disabled. This is a small safety guard, not a full security sandbox.

• ?ex=live-loop loads one built-in example by name
• ?src=... loads base64-encoded JavaScript source into the editor
• ?tfi=...&tfi-id=bass loads one URL TFI preset with id bass
• ?tfi=...,... with ?tfi-id=a,b loads multiple URL TFI presets