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With the BSEC2 library, a timestamp in nanoseconds is required to be provided for each sensor measurement. The documentation says that it is fine if this is a value that starts at zero and is increased over time. Must this value remain consistent during power cycles, when the state is re-loaded from flash into the system, or can the timestamps start back at zero in this case? I ask as I am working on a project that will likely experience occasional power interruptions, but I do not have a way to maintain a clock between these interruptions. Here is an example scenario (note that I am using smaller numbers for the timestamp, to keep it simple). Start up Sample at t=0 Sample at t=5 Save state Sample at t=10 Power Loss Load State Sample at t=0 Sameple at t=5 (continue indefinitly).   Is this allowed, must the timing be preserved after power loss, so that the post-power loss samples are values greater than 10 (which would thus require me to integrate an external method for keeping track of  time)? ... View more

I'm working on a small personal environmental monitoring project that uses the BME688 alongside the BSEC2 library, and I am confused about some of the behvaior related to the sample rate of virtual sensors, as documented in section 1.2.4 of the integration guide PDF, and in the example code provided in the library. Looking through the integration guide PDF and the examples provided by Bosch, I'm confused as to how the sample rate for the virtual sensors are supposed to be configured. The array that is passed into bsec_update_subscription allows for a different sample rate to be set for each virtual sensor, but the documentation, as well as the provided examples make it look as if only one sample rate should be used for all of the different virtual sensors. Should I be using the same sampel rate for all sensors, or can I mix which sensors are used (i.e. some sensors in ULP mode, and others in SCAN mode)? I'm confused as to what sample rates the different virtual sensors support. In the bsec_iot_example.c file that is provided with the BSEC library, the sample rate of the gas index and estimate sensors are set to BSEC_SAMPLE_RATE_LP, however the integration guide PDF that is provided with the library states (in section 1.2.4) that these sensors only support BSEC_SAMPLE_RATE_SCAN. Is this an error in the integration guide, or in the example code? Looking at the integration guide (in section 1.2.4), it seems that the gas index features and the IAQ/VOC/eCO2 measurements are not able to operate in the same sample modes, and thus likely cannot be operated at the same time. This is further indicated by the statements that the sensor shall not perform both at once, and shall not switch between different modes during the lifetime of the sensor. Does this mean that to be able to perform both types of measurements, multiple sensors must be used? In the integration guide (in section 1.2.4), it states that " the user shall not switch between different modes during the lifetime of a given sensor." What is the meaning of "lifetime"? Does this mean for an operational purpose, or that once I start using the sensor in one mode, I should never change it again, even if I intend to use the sensor in an entirely different prototype project? ... View more