I'm going to use FXAS21002 3-axis gyro in car crash test environment (cars, barriers, dummies...).
The plan is to read gyro reading with a steady 500 Hz rate ie. new reading every 2 ms. The rate could be lower down to 200 Hz (5 ms) but according to spesification the FXAS21002 should be able to 500 Hz.
It is vitally important that all 3 axes give there reading at the same instant. I can live with non-simultaneous readings if I know the time difference between the axes?
Could you comment on these questions:
1. The specification sheet does not tell if I can somehow trigger a new measurement cycle. Is it possible to trigger a reading to make a more precise and externally controlled timing?
2. What is the time difference between the readings of the axes?
3. Can an interrupt pin tell whether ALL three axes have a new reading, not just one axis.
4. If I read the three readings is it possible that a new reading is updated in the output register so that one byte is from a previous reading and the other from a new reading? Or eg. the X axis reading is new and the Z axis reading is old.
5. How the sensor actually makes it reading rate (eg. max speed of 800 Hz)? It does not have a clock input. How accurate this rate is?