Pixhawk GPS/NMEA Serial Configuration

• Pixhawk 2.4.8 clone running ArduRover 4.7.0
• DFRobot RTK LoRa kit (Quectel LC29H, NMEA output over UART) — base and rover, LoRa link confirmed working, rover shows solid RTK lock
• Connected to the Pixhawk’s GPS port

Problem: Mission Planner shows “EKF3 waiting for GPS config data” and never acquires a position. Already tried:

• GPS_TYPE = 5 (NMEA), SERIAL3_PROTOCOL = 5
• GPS_AUTO_CONFIG = 0
• Every supported baud rate on SERIAL3_BAUD, rebooting each time
• Swapping TX/RX (original orientation confirmed correct — receiver lost lock when reversed)
• Confirmed the module’s I2C/UART switch is set to UART

Looking for someone with hands-on ArduPilot experience to diagnose over a screen-share session. I can provide parameter files, logs, and photos of the wiring. Remote only — I’ll do the physical work on my end.

Skills: ArduPilot / Mission Planner, Pixhawk, GNSS/NMEA, embedded serial debugging