Does the BNO055 come with preloaded firmware that is internally stored and automatically loaded by the bootloader?
The BNO055 has Firmware which is already loaded into the chip so you can directly use it without downloading the firmware again.
There is a section in the datasheet that talks about possible firmware updates. If there is a firmware update and I want to update my device, what pins do I need to be able to control?
To update the firmware of BNO055, you need to connect nBOOT_LOAD_PIN (pin 4), reset pin (pin 11) and protocol pin.
Please see page 96 and 97 of the BNO055 datasheet for pinouts.
All information was provided by Bosch Sensortec’s Forum.