Pixel Ring

A headless daemon + web UI to drive the ReSpeaker USB Mic Array v2.0 LED ring (USB 0x2886:0x0018, XVSR3000). It mirrors a voice assistant's state on the ring, doubles as a LedFx output device, and gives you full manual control over animations, colors, and the on-board DSP.

Independent and MIT-licensed. The device's USB protocol is public (Seeed wiki); the driver and DSP code here are clean-room rewrites — no GPL respeaker code is reused. (The old Raspberry-Pi SPI/APA102 path is gone.)

Features

• Animation engine — Echo/Google-style assistant animations (wakeup/listen/think/speak) plus creative effects (rainbow/comet/breathe/wipe/chase), recolorable, all rendered host-side and pushed to the ring via USB.
• Assistant mode mirroring — connects as a client to a voice assistant's WebSocket and animates the ring per mode (idle/listening/thinking/speaking/boot). The assistant needs no changes; it's purely a consumer of its public mode broadcast.
• LedFx output device — listens for DDP frames, so LedFx can drive the ring with zero LedFx changes (add a DDP device → 127.0.0.1:4048, 12 pixels).
• REST + WebSocket API — manual control, per-LED override, live ~20 fps frame stream.
• Web control UI — a Vite/React/MUI app served by the daemon (also builds as an embeddable IIFE for a host frontend).
• DSP access — read/write all XVSR3000 tuning parameters (DOA, VAD, AGC, AEC, noise…).
• Calibration & display — DOA offset/flip, output gamma, and a preview-orientation transform, all persisted.

Requirements

• A libusb backend + USB access to the device's vendor interface (one-time per OS — see USB device setup). This is the only hard requirement — it's a system driver, needed whether you run from source or the standalone binary.
• To run from source: Python ≥ 3.10 and uv (or pip). Node 18+ only if you want to build the UI yourself.
• To run the standalone binary: nothing else — Python, uv and Node are all baked in.

The daemon and UI are cross-platform (Windows / Linux / macOS). Only the USB setup and the autostart mechanism differ per OS; nothing in the code changes.

USB device setup (one-time)

• Windows — bind a WinUSB/libusb driver to the device's vendor/control interface with Zadig (pick the ReSpeaker control interface, not the audio one).
• Linux — libusb is usually already present. For non-root access, add a udev rule:

  echo 'SUBSYSTEM=="usb", ATTRS{idVendor}=="2886", ATTRS{idProduct}=="0018", MODE="0666"' \
    | sudo tee /etc/udev/rules.d/99-respeaker.rules
  sudo udevadm control --reload-rules && sudo udevadm trigger

  (or just run the daemon with sudo).
• macOS — brew install libusb.

LED control + DSP tuning use endpoint-0 control transfers, so they coexist with the mic (the USB audio interface stays usable) on all three.

Quick start

Three ways to run it — all serve the same UI/API on :9700:

Install (have Python?) — one command, cross-platform, web UI bundled in:

uv tool install yz-pixel-ring    # installs the `yz-pixel-ring` command, on PATH
#   or:  uvx yz-pixel-ring        (run without installing)
#   or:  pipx install yz-pixel-ring

Standalone binary (no Python needed) — run yz-pixel-ring(.exe) directly. See Standalone binary for how to build it.

From source (devs):

uv venv
uv pip install -e .              # or: uv pip install -e ".[dev]" for tests + mock
uv run yz-pixel-ring             # follow assistant + REST/UI on :9700, DDP on :4048
#   (equivalently: python -m yz_pixel_ring)

Any way, open http://127.0.0.1:9700 for the control UI. (All still need the one-time USB driver step.)

Useful flags / env:

--port / RING_DAEMON_PORT     REST + UI + WS port (default 9700)
--ws-url / JARVYZ_WS_URL      assistant WebSocket (default ws://127.0.0.1:8765/ws)
--no-jarvyz                   don't connect to the assistant
--ddp-port / RING_DDP_PORT    DDP listen port (default 4048)
--no-ledfx                    don't listen for LedFx DDP frames

How it works

The daemon owns the USB ring and runs a ~20 fps frame loop. Frames come from one of three input sources, by priority:

LedFx (DDP, UDP :4048)  >  manual (REST)  >  assistant mode (WebSocket)

LedFx takes over while DDP frames arrive and falls back after a 1 s timeout. The current frame + live state are broadcast over a WebSocket so the UI renders a live ring preview without polling.

REST API (port 9700)

Method & path	Purpose
GET /health, GET /state	liveness; full snapshot
POST /mode {state}	inject an assistant mode
POST /follow {enabled}	follow assistant (auto) vs. manual
POST /effect {kind,name,style,color,palette,intensity,doa_*}	manual animation
POST /color {r,g,b,intensity} · POST /off	solid color / off
POST /leds {leds:[[r,g,b],…]}	raw per-LED frame (custom)
GET /modes · PUT /modes/{mode} · POST /modes/reset	per-mode animation config
GET /tuning · GET|POST /tuning/{name}	DSP parameters
POST /doa_offset {value,flip} · POST /gamma {value} · POST /preview {rotation,mirror}	calibration / display
WS /ws	live frame + state stream

LedFx integration

In LedFx, add a DDP device → host 127.0.0.1, port 4048, pixel count 12. While LedFx streams, the ring shows its output; when it stops, the daemon resumes assistant/manual. Tip: let LedFx own brightness and keep the daemon's gamma at 1.0.

Configuration & persistence

Stored under ~/.yz-pixel-ring/:

• modes.json — per-mode animations (colors, DOA settings).
• config.json — DOA calibration (doa_offset/doa_flip), gamma, preview orientation.
• daemon.log — output when run headless (e.g. via Task Scheduler).

DSP tuning parameters live on the device (runtime only; reset on power loss).

Standalone binary (no Python)

For a friendlier hand-off, the daemon (web UI bundled in) can be packaged into a single self-contained executable with PyInstaller — no Python or uv needed on the target machine:

cd ui && npm install && npm run build:pages && cd ..   # build the UI once
uv run --extra build python tools/build_exe.py         # -> dist/yz-pixel-ring(.exe)

Then just run dist/yz-pixel-ring (or double-click it). It serves the UI on http://127.0.0.1:9700 exactly like uv run yz-pixel-ring, and takes the same flags/env vars.

Build knobs (env vars, forwarded to yz-pixel-ring.spec):

YZ_CONSOLE=0   no console window — output goes to ~/.yz-pixel-ring/daemon.log
YZ_ONEDIR=1    a folder instead of one file (faster start, fewer AV false positives)

⚠️ The binary still needs the one-time USB driver step. PyInstaller bundles Python and the deps, but it can't bundle a kernel driver — the libusb backend is a system driver (installed by Zadig on Windows / udev on Linux / brew libusb on macOS, see USB device setup). The exe removes the Python prerequisite, not the driver prerequisite. PyInstaller produces a binary for the OS you build on, so build on each target OS.

Autostart

Run the daemon at login with auto-restart. Replace <dir> with the project path (or point at the standalone binary above instead of the .venv Python).

Windows (Task Scheduler)

$exe = "$PWD\.venv\Scripts\pythonw.exe"
$action  = New-ScheduledTaskAction -Execute $exe -Argument "-m yz_pixel_ring" -WorkingDirectory "$PWD"
$trigger = New-ScheduledTaskTrigger -AtLogOn -User $env:USERNAME
$settings = New-ScheduledTaskSettingsSet -RestartCount 3 -RestartInterval (New-TimeSpan -Minutes 1) -ExecutionTimeLimit ([TimeSpan]::Zero)
Register-ScheduledTask -TaskName "PixelRingDaemon" -Action $action -Trigger $trigger -Settings $settings -Force

Linux (systemd user service)

~/.config/systemd/user/yz-pixel-ring.service:

[Unit]
Description=yz-pixel-ring daemon

[Service]
WorkingDirectory=<dir>
ExecStart=<dir>/.venv/bin/python -m yz_pixel_ring
Restart=always

[Install]
WantedBy=default.target

systemctl --user enable --now yz-pixel-ring

macOS (launchd agent)

~/Library/LaunchAgents/com.yeonv.yz-pixel-ring.plist:

<?xml version="1.0" encoding="UTF-8"?>
<plist version="1.0"><dict>
  <key>Label</key><string>com.yeonv.yz-pixel-ring</string>
  <key>ProgramArguments</key>
  <array><string><dir>/.venv/bin/python</string><string>-m</string><string>yz_pixel_ring</string></array>
  <key>WorkingDirectory</key><string><dir></string>
  <key>RunAtLoad</key><true/>
  <key>KeepAlive</key><true/>
</dict></plist>

launchctl load ~/Library/LaunchAgents/com.yeonv.yz-pixel-ring.plist

Project layout

yz_pixel_ring/
  __main__.py            python -m yz_pixel_ring -> daemon
  daemon.py              the daemon (REST + WS + DDP + assistant bridge)
  animations.py          pure frame engine
  led.py                 USB LED control
  tuning.py              DSP read/write (DOA / VAD / AGC / AEC / …)
tools/mock_jarvyz_ws.py  mock assistant WebSocket (offline testing)
ui/                      web control UI (Vite + React + MUI)
docs/                    device reference notes

Development

uv run pytest                    # hardware-free engine tests
cd ui && npm install
npm run dev                      # Vite dev server on :9701 (talks to the daemon via CORS)
npm run build:pages              # standalone SPA -> yz_pixel_ring/_ui (served by the daemon)
npm run build:lib                # IIFE -> ui/dist-lib (host-embeddable, window.YzPixelRing)

See ui/README.md for the web UI (build modes, structure, how it talks to the daemon).

Cutting a release

python tools/release.py            # bump patch, commit "Release x.y.z", push
#   --minor / --major / --set X.Y.Z   other bumps;  --no-push to stop before pushing

The push triggers the Builder workflow, which builds the per-OS binaries + IIFE + wheel, publishes a GitHub Release, and uploads the wheel to PyPI (OIDC, no token).

License

MIT © Yeon (Blade)