Hello I_Bela,
The firmware has been compiled, ou do not need to compile it separately. You can see on GitHub that it is in the form of header files. You only need to load the host into the sensor through the I2C interface through the example code. https://github.com/BoschSensortec/BHY2-Sensor-API/tree/master/firmware/bhi260ab
If you don't want to load firmware through host, you can refer data sheet and use standalone boot mode. BHI260AB can be configured to boot autonomously from an external flash device. You only need to read algorithm output from BHI260AB.
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