LSM6DSO timestamp for external sensor event

[el659]

Hi @Federica Bossi , I have a question about timestamp and the external sensor event.

According to the application note of LSM6DSO (image above), timestamp's register is written when main sensor or external sensor event occurs. I have no problem with main sensor event because it seems like the timestamp register is written when the new data from accelerometer and gyroscope is ready to be read. However, I am unclear about the external sensor event since I wouldn't directly be polling data from the external sensor but through LSM6DSO's sensor hub.

My questions is, for instance, assuming I will be reading timestamp data directly from the timestamp register on LSM6DSO, if I have LIS2MDL connected to LSM6DSO as sensor hub slave, does it mean that the timestamp register will be filled with data when the data from LIS2MDL arrives at LSM6DSO's FIFO through sensor hub operation?

Thank you,

[Federica Bossi]

Hi @el659 ,

There are two possible scenarios:

• If START_CONFIG = 0 (sensor hub trigger signal is the internal accelerometer/gyro data-ready signal), the timestamp of the trigger event is written in FIFO (even if a main sensor is not batched).
• If START_CONFIG = 1 (sensor hub trigger signal external from INT2 pin), the timestamp of the trigger event is not written in FIFO. If a main sensor is batched, the timestamp is written in FIFO as usual.