Supported Firmware
Firmware can be flash via Mission Planner or QGroundControl. It can also be downloaded here: https://firmware.ardupilot.org/
PX4 Firmware Target: FMUv6x
Ardupilot Firmware Target: Pixhawk 6X
PX4
Support in PX4 1.14.3 release and later.
Ardupilot
Supported in 4.5.0 stable release and later.