SX1262 liveness over WebUSB → CH341

Checkpoint A (hardware half): proves the protocol + WebUSB reach a real LoRa radio, no WASM yet.

← Full node

Requires Chromium (Chrome/Edge) over http://localhost or https. Plug in a CH341-based LoRa adapter (Meshstick / MeshToad / Pine64 LoRa hat). On Linux the CH341 must not be claimed by a kernel driver; on Windows it needs the WinUSB driver (Zadig). Default filter VID 0x1A86 / PID 0x5512.