MPU-9250: mpu_lp_motion_interrupt() gives no interrupts

Hi all,

I'm using the MPU-9250 with motion driver 5.1.2.

At the moment everything is working fine in terms of configuring the MPU-9250, receiving interrupts and reading data.

I want now to call the mpu_lp_motion_interrupt() function once everything has been setup and interrupts have been configured to wake on motion.

However, even if I use very low thresholds (e.g. params (1,1,80)), if I call this function then I never get interrupts even when shaking the MPU-9250 a lot for many seconds. I also tried (500,1,5) from the example provided with the driver with the same results. The function is returning 0 (success) in all cases.

If I call it with parameters (0,0,0) to disable it then I get interrupts as normal.

I've compared what I'm doing to the motion_driver_test.c example and can't see anything obviously wrong.

What can I do to get this working please?

Many thanks for your time!