IMU BatchSampler - How to use it?

The wiki page documentation about the IMU BatchSampler provides obsolete information on how to use it, referencing parameters that do not exist anymore or have been renamed , in current 3.5 release.

(page here : http://ardupilot.org/copter/docs/common-imu-batchsampling.html)

As a consequence I do not find how to activate the logging for IMU BatchSampler and I do not find how to activate the high speed sensor rate logging for the Accel IMUs.

As result, I also do not find the two types of dataflash log messages involved in batch sampling, ISBH and ISBD.

The mentioned parameters that are listed in the wiki and do not exist anymore are:
INS_BAT_MASK
IMU RAW
INS_LOG_BAT_OPT
INS_LOG_BAT_CNT
INS_LOG_BAT_MSK
INS_LOG_BAT_LGIN
INS_LOG_BAT_LGIN

What are the current 3.5 parameters replacing these ones ?
How is BatchSampler enabled in 3.5 ?
How are FFT messages logged in the dataflash logs in 3.5 ?

Thanks in advance for any help

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The wiki page documentation about the IMU BatchSampler provides obsolete
information on how to use it, referencing parameters that do not exist
anymore or have been renamed , in current 3.5 release.

Sorry, things have changed a lot in master - and the upcoming Copter
release.

It deserves a note on that page. I wonder if we should do something like
the C++ docs to, with their (e.g) “(since C++17)” tags (see
http://en.cppreference.com/w/cpp/container/vector). Versioning on our
Wiki is tough since the information you’ve come across is useful for
people running master, but confusing for those running stable versions of
anything but Rover.

IMU RAW

That’s not actually a parameter - that’s a bit in the existing LOG_BITMASK
which turns on “very, very fast” continuous sampling of gyros and accels.
It’s role is replaced by batch sampling.

How is BatchSampler enabled in 3.5 ?

Sorry, it’s not - you only have the continual-sampling method.

How are FFT messages logged in the dataflash logs in 3.5 ?

No ISBH/ISBD messages are available in 3.5 - you can fft the data
present, but it’s prone to error.

If I understand what you’re saying is that the BatchSmapler is not existing in 3.5 ? In which release will it be then and why have already a wiki page if the feature does not exist yet ? Maybe a message saying something like : “this feature is not yet existing in current release” would be useful (I lost a full day trying to debug and make it work…)