I have read a previous post where it gets stated that firmware 4.0 has a serious bug when used in autotune mode, while I am waiting for a new stable release, I was wondering if after performing Autotune with firmware version 3.6.11 the PID values calculated during this procedure will be kept after upgrading to firmware version 4.0.X
Yes, there’s a bug in AutoTune which can cause a crash (although it’s quite unlikely actually).
The PID values calculated with a 3.6.x AutoTune will be kept as part of the upgrade to Copter-4.0.x.
Once you elect to keep the PIDs from autotune, those are just the PIDs. It doesn’t actually matter whether those PIDs came from autotune or you typing the numbers in by hand. Autotune just saves the PIDs into memory and that’s it. Whatever value is saved gets converted.