uAvionix now supports seamless integration of ping200X and ping200XR transponders with ArduPilot – sUAS News – The Business of Drones
GPS/Compass (landing page) — Copter documentation
UBlox GPS + Compass Module — Copter documentation
Setup & Getting Started (Ardupilot) - Holybro Docs
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Tutorial: Connecting other GPS modules to ArduPilot - Blogs - diydrones