BSEC runs a default configuration which may be customized to better match your platform/use-case requirements. For instance, a configuration string includes information about the supply voltage of the BME680, duration between measurements and time constant for background calibration. Information about the default configuration used by BSEC and alternative settings available are described in the Integration Guide of BSEC's release package.
BSEC processes run in RAM, meaning a reset of the library (e.g. due to MCU/CPU reset, program restart, etc.) will loose all information about the state of the internal algorithms and variables. BSEC therefore provides interfaces to backup or load a "state string". This state string is meant to be saved in some sort of external non-volatile memory, and reloading a valid state valid then allows one to restore the state of all BSEC modules, including background calibration history, and continue operation even following a restart.
