BNO055 register 0x3B bit 0 has defination of accel unit, you can select the output unit as mg or m/s2.
This means the accel data was already convert inside BNO055 . and directly output as mg or m/s2. if you select output unit as mg, then the sensitivity is 1mg/LSB.
When select the fusion mode, the accel range is fixed to 4G range, you can't change the range by yourself. the output accel value in register on page 0 was converted according to its output unit.
WHen select non-fusion mode, you can change the acc range in register 0x08 on page 1 to other range like 8G, the maximum range of accel will be changed, the internal sensitivity from internal MEMS sensor output was also updated. but the accel value stored into BNO055 acc data read out register will be still 1mg/LSB. those value are processed by BNO FW, converted to the desired unit, not directly map the output register from internal MEMS sensor.
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