PX4 FMU v1.6 compatible with APM 3.1 (without PX4 IO)?

Hi. I have an older PX4 board (labled PX4FMU v1.6) and no PX4 IO board.
Is it possible to use APM firmware with this setup to control a quadcopter?

I also have an old 3DRobotics GPS (labled LEA6 v1.1). It has no compass. Is it possible to use this GPS together with the above setup to achieve position hold? Or do I need an additional external compass module?

Thanks for your help,

Hi Jonek,

I think you need this: http://copter.ardupilot.com/wiki/px4fmu-only-wiring/


No, it is not possible to use Arducopter 3.1 without the IO board.

Flying with just the FMU is not officially supported (it is not part of our testing) but as you say it has been working. I think we overlooked this in 3.1 and the problem is you can’t arm. This should be resolved in master.

Please try using master (also known as latest firmware.diydrones.com/Copter/latest/PX4-quad/


That should allow you to arm and the motors to spin.

Be very cautious if you actually fly master. There are some known issues with the throttle pulsing and a massive wobble at waypioints during missions, but please report back if you can arm.

is it resolved in master ?

how to flash a specific firmware with mission planner ?.