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    BHI360 + BMM350 : No Mag data on custom board

    BHI360 + BMM350 : No Mag data on custom board


    Hello Bosch Sensortec community,

    I am working on a custom board with a BHI360 and a BMM350 connected as an external sensor in I2C. I am writing my own library to communicate from my host CPU to the BHI360.

    Here are some information about my setup:

    - I followed the BHI360 datasheet (4.1.2) to connect the BMM350 (see my schematic below).

    - I successfully flashed the "BHI360_BMM350C" firmware.

    - My host CPU can read the BHI360 Acc and Gyro data without any issue. (Although the gyro sensor self-test reports an Error 7: Multiple Axis Failed or Single Test Failed.)

    - The BMM350 self test returns 0: Test passed. However, when I try to use any virtual sensor using the BMM350 (such as the Magnetometer corrected or the rotation vector), I have the following errors for the Magnetometer: (0x24 Sensor Error: No Valid Data) and (0x25: Slow Sample Rate).

    - The virtual sensor rate is set to 100 Hz. I am using the non-wake up FIFO.

    - The Physical sensor information for the BMM350  are shown below, one strange thing is that its Master interface flag bits are "0b1010", which is not one of the possibilities of Table 65.

    Here are my questions:

    - Do you have any idea why I cannot get data from the BMM350 ? Do I have to do additionnal configuration steps besides loading your firmware and starting a virtual sensor to make it work ? Do I need to manually configure the BMM350 using the soft pass-through feature of the BHI360 (13.2.4) ?

    - Is there something wrong with my schematic ? I didn't wire the interrupt pin of the BMM350, is it mandatory?

    - What can I do about the Gyroscope self-test error ? The output data looks ok, it's not 0 when still, but the variations when I move the sensor around make sense.

    Thank you very much for your help.

    10 REPLIES 10

    Unfortunately, no. We endded up modifying our hardware (i.e. connecting the BMM350 interrupt line to the BHI360 JTAG_DIO pin). It's a shame we have to adapt our hardware to their firmware and not the contrary, but we figured it would take more time asking them to make a change... That being said, I still opened a ticket on the boschsensortec Githbub page, hopefully we'll get some feedback there.