LumiDI

Control a WS2812B LED strip from Ableton Live via a Teensy 4.0 running USB-MIDI firmware.

Ableton Live
  └─ LumiDI (Max for Live device — animation engine, streams pixel frames as MIDI notes)
       │ track "MIDI To"
       ├──> Teensy 4.0 USB-MIDI ──> LED strip          (the real thing)
       └──> IAC Driver bus ──> web simulator (Chrome)  (for testing, no hardware)

Components

• hardware/teensy/ — PlatformIO firmware. Notes 0–125 set one color channel of one pixel (note/3 = LED, up to 42 pixels; note%3 = R/G/B, value = velocity×2, velocity 1 writes 0), note 127 latches the frame. One build fits any strip length.
• ableton/ — the LumiDI Max for Live MIDI effect: solid / pulse / chase / rainbow animations, HSV color, brightness, speed, tempo sync, per-strip pixel count, and multi-strip layouts (several devices rendering one animation across their strips). See ableton/README.md.
• web/ — the landing page plus a browser strip simulator (under /simulator/) that listens to the same MIDI stream. See web/README.md.

One-time macOS setup for the simulator (IAC bus)

1. Open Audio MIDI Setup → Window → Show MIDI Studio.
2. Double-click IAC Driver, check Device is online (an "IAC Driver Bus 1" port appears).
3. In Live → Settings → Link/MIDI, make sure the IAC output is not used as a Track input elsewhere (avoid feedback loops); no other config needed.

Workflow

1. Build the device: python3 ableton/build_amxd.py, then drag ableton/LumiDI.amxd onto a MIDI track.
2. Set that track's MIDI To → IAC Driver Bus 1 and open the simulator (see web/README.md) to preview.
3. Switch MIDI To → Teensy MIDI to drive the physical strip.