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    BNO055 Calibration, Cal. reuse, Cal. status, Run modes, Offsets, Axis mapping

    BNO055 Calibration, Cal. reuse, Cal. status, Run modes, Offsets, Axis mapping

    New Poster


    I am evaluating the BNO055 using a Microchip Xplained Pro Kit and a Raspberry Pi, connected via I2C bus.

    I've managed to set basic settings such as run mode, read the Calibration status byte, etc. However, I am not sure which data can be read in which run mode respectively when exactly some data is updated by the sensor controller. My questions are:

    1. Is it correct, that the calibration data (addresses 0x55 to 0x6A) can only be read in CONFIGMODE?

    2. Is it correct, that the calibration status byte (address 0x35) can only be read in a run mode, i.e., any operation mode other than CONFIGMODE, e.g., NDOF?

    3. Given the sensor was fully calibrated, i.e., the CALIB_STAT byte at 0x35 holds 0xFF, and the calibration data (0x55-0x6A) was stored on the host system and uploaded to the sensor in the following fashion: Calibrate, save data, power cycle the sensor, ensure sensor is in CONFIGMODE, write calib. data to according addresses, put sensor into operation mode (e.g., NDOF), read calibration status. Should the CALIB_STAT byte then immediately be 0xFF and the sensor calibrated and ready to use? I observed the sensor not showing fully calibrated after uploading the calib. data.

    4. Is it possible to force the sensor to not update the calibration data after it was uploaded? Can it be done reading only raw data from the sensor and using the BSXlite sensor fusion software?

    5. Is it correct, that using the default axis mapping P1 (AXIS_REMAP_CONFIG = 0x24, AXIS_REMAP_SIGN = 0x00) the forward direction of the measured heading is as is depicted using the red arrow in the attached picture? I observed 90 degree offsets to magnetic north which makes me question the axis mapping.

    Thanks in advance for your answers!

    5 REPLIES 5

    Community Moderator
    Community Moderator

    Hello DRA,

    Does BSXlite host side fusion software support disabling of continous calibration?
    The running or stopping of BSXlite can be determined by the host.

    ad 5.: The read arrow in the figure denotes positive X axis.
    It should be P0 according your description.

    6. How is HEADING defined? Is it the angle between configured sensor positive X axis and true north?
    You could refer it from BNO055 data sheet:

    BNO055 coordinate system.png