Bring your Lutron HomeWorks Interactive system into the modern smart home.

ESP32-based replacement processor

A drop-in processor that speaks both Lutron bus protocols natively.

The Lutron Lighting Upgrade firmware runs on a single ESP32 and replaces the original HomeWorks Interactive processor at the heart of the installation. On the keypad bus it speaks StarBus over RS-485 — 9,600 baud, differential signaling, full bidirectional state broadcast so every keypad's LEDs reflect the current scene. On the dimmer bus it speaks the 15V Vareo protocol — 120 Hz line-synced clock, ten phase-angle brightness levels per zone. Above both buses sits a state manager, a scene engine, WiFi station mode, and a local REST API on port 80 — and the Matter-enabled build is in active development.

• StarBus RS-485 keypad protocolNative RS-485 driver for the Lutron StarBus keypad bus — 9,600 baud, 8N1, differential A/B signaling on the 4-wire bus. Runs on its own dedicated processor core for predictable, real-time bus timing. PRESS commands from any keypad on the bus flow in; state-bit updates broadcast back so every keypad on the bus shows consistent scene state on its LEDs.
• Vareo 15V dimmer-bus driverNative driver for the 15V Vareo phase-angle dimmer bus — 120 Hz clock synced to the AC line, 1,300 ms per command frame, ten brightness levels per zone (0 off through 9 full). Reverse-engineered from oscilloscope captures of the original Lutron processor's traffic and fully documented by A1SI engineering.
• Local REST API on port 80A local-network HTTP API exposes the system to anything that speaks JSON. GET /api/status returns the full state. GET /api/zones returns brightness for every zone. PUT /api/zones/{id} sets a zone's brightness 0–9. POST /api/scenes/{id} activates or deactivates a scene. No cloud round-trip, no proprietary control protocol — just plain HTTP on the customer's LAN.
• Scene system — button → scene → zonesA central scene engine maps each keypad button to a scene, and each scene to a set of (zone, on/off, brightness) actions. Press a button on a keypad or POST a scene activation over the REST API and the same engine drives the same dimmers — keypad state and API state stay coherent.
• WiFi station modeThe ESP32 joins the customer's existing WiFi network in station mode. That's the network the REST API listens on, and the network any home-automation hub (Home Assistant, openHAB, Node-RED, custom HTTP client) reaches the system through. No separate hub, no dedicated wiring.
• Matter protocol support (in development)A Matter-enabled build is in active development. When Matter ships, the same processor exposes the Lutron installation as a Matter device to Apple Home, Google Home, Samsung SmartThings, and Amazon Alexa over Thread or WiFi without changing any of the underlying bus drivers.