Which version of the ArduSub firmware is suitable for the Cube Orange?

Hello,
I have tried making the ArduSub-Cube-Black firmware work with Cube Black. And then failed.
Next, I have tried making the ArduSub-fmuv3 firmware work with Cube Black. And then I succeeded.
Right now, I have intention to purchase a Cube Orange, and want to integrate it into the ArduSub system.
So, I would like to know which version of the ArduSub firmware is suitable for the Cube Orange.
By the way, does the Cube Orange belong to the FMU_v3? If not, which version of FMU does the Cube Orange belong to?
Looking forward to your reply. Thanks!

May I know how did you fail to upload firmware?
I have tried to upload ArduSub from Mission Planner to Cube Black and Orange.
Both works fine.

Cube Orange is FMU_v3

The Cube Black with firmware ArduSub-Cube-Black-v4.0 and above does not autoconnect to Companion computer. QGC will appear with video, but there is no vehicle detected.

The Cube Black with firmware ArduSub-Cube-Black-v4.0 and above does not autoconnect to Companion computer. QGC will appear with video, but there is no vehicle detected.

Hi Lucy, I assume you’re trying to connect with a RPi companion? If so this is a known issue 322 with ardusub companion and cubes.

I found I could get my Cube Purple to connect but restarting Mavproxy from the companion web interface. If you’re using Companion 0.0.25 you can just hit the ‘Stable’ button to try to flash the ardusub firmware. It won’t be able to do that but it restarts Mavproxy at the end and you get the connection.

I hope this helps.