I although I don't use the arduino feature myself, I was approached to look into an issue on behalf a frustrated client who couldn't figure out why they experiencing erratic behaviour with peripherals on the A9 side after launching a arduino script. The current arduino launcher goes the against the grain of when the M4 should be initialised so that the kernel is aware of it. Therefore as a warning if your running arduino scripts don't expect all peripherals to work correctly on the A9 side.
You notified the Udoo team with more details I presume? For our understanding: What peripherals were not working correctly in your clients example?
Hi @jas-mx, can you give us more info? Which peripheral???? Doing what you get an erratic behaviour? @ektor5