Pitch reversal after upgrade

After upgrading to 2.9.1b my quad immediately flipped over its nose when I attempted takeoff.  It was flying very well prior to the upgrade so there is no hardware problem.  We did the following tests.

- Motors are turning the correct directions and props are on right

- We get the correct responses from the RC controls, per other threads here.  It would not make sense to change the radio anyway because the APM would still be attempting to correct the wrong direction to maintain stability.

- Hand holding it, it is clear the pitch is reversed. When tilting it forward by hand it wants to tilt further. Tilting backwards it attempts to tilt further backward.

- Setup parameters show X configuration

- After noting this behavior we did an ESC calibration and an accel calibration and the behavior did not change.

- It would seem like we need to reverse the pitch in the APM and there are several references in these discussions to doing that.  However I’m not finding any parameter in MP for the pitch sense or reversal. 

Any guidance on how to fix this would be appreciated. 

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  • Turns out I had loaded the 8 motor X config firmware rather than the 4 motor.  I just didn't look closely enough at the configurations on the firmware upgrade page.  I've redone the radio cal, ESC cal, and accel cal and will test further.

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