Copter-4.2.1-rc1 available for beta testing

Copter-4.2.1-rc1 has been released for beta testing and should be available for download within a few hours of this post.

The changes vs 4.2.0 are in the ReleaseNotes and copied below.

  1. CAN ESCs bus bandwidth efficiency improvements (see CAN_Dx_UC_ESC_OF parameter)
  2. DShot timing improvements to support for ESC variants
  3. LOITER_TURNS command radius max increased from 255m to 2550m (but only 10m accuracy when over 255)
  4. Luftan EFI measures fuel consumption (see EFI_COEF1, EFI_COEF2)
  5. Bug fixes
    a) CAN ESCs work on boards with no safety switch (e.g. MatekH743)
    b) Inflight Compass calibration checks GSF yaw estimate is good
    c) LOITER_TURNS command’s Turns field limited to 255 (previously would wrap to lower number)
    d) NeoPixel colour fix
    e) Precision Landing maintains yaw during retries

The changes fixup a few things that came up at the end of beta testing but weren’t critical enough to block the stable release.

Any testing and feedback is greatly appreciated!


Some testing done.
12 km flight in quite good weather conditions (current 15A towards east, 9A west). Trip partially over the sea. Video from camera smooth, no oscillations or instabilities. Motors only slightly warm. In general no issues found. :slight_smile:



Thanks very much for the testing and reporting back!

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