Purple Keyboard BT is a minimal ESP32 device that emulates a Bluetooth keyboard and automatically switches between two windows on macOS every 10 seconds — hands-free, indefinitely.
The primary use case is dual-screen monitoring: open two Chrome windows with your dashboards, Grafana panels, or log streams side by side, pair the device, and it will cycle between them on its own. No software to install on the host, no scripts to run, no browser extensions.
Getting started
Getting started is three steps:
- Flash your ESP32-WROOM-32 using the Flash button below
- Power it via USB-C (any phone charger or powered hub works)
- Open Bluetooth on your Mac and pair the device named Purple Keyboard
That's it. The device starts switching windows immediately on connection.
To pause, simply unplug the USB-C cable. Reconnect when you need it again — macOS will re-pair automatically within a few seconds.
No pairing codes, no drivers, no configuration needed. The firmware runs entirely on the ESP32 and communicates over standard Bluetooth HID, which every modern Mac, Windows PC, and Linux machine supports natively.
Keywords: esp32, ble, keyboard, automation