iNemo (LSM6DS3) significant motion detection not working

[Alan Chambers]

Posted on January 16, 2017 at 18:26

I am trying to configure the iNemo to assert INT1 when significant motion is detected. I have followed AN4650 closely (the configuration matches that given in AN4650 Section 6.2 at the end of the section), but no interrupt is ever generated. I am using a STEVAL-MKI160V1 plugged into another board. I'm probing INT1 on the STEVAL while shaking the board and otherwise trying to simulate walking, running or other motion. I have tried reducing the threshold, including DEB_STEP, but nothing has worked.

Does this mode actually work as documented? Do other registers need to be written to make this work? I have the FIFO turned on, and it accumulates data at 26Hz as expected.

Thanks.

[Miroslav BATEK]

Posted on January 18, 2017 at 14:55

Hello Alan,

yet, the significant motion works as described in the application note. The 

algorithm is based on pedometer. Significant motion is detected if the number of steps performed by the user upon a change of location is higher than a set limit. So you have to simulate walking to trigger the interrupt.

How do you probe the INT1 signal? The interrupt signal generated by the significant motion function is pulsed, maybe you missed the pulse. You can set the LIR bit in TAP_CFG register, then the interrupt will be active until you read the FUNC_SRC register.