How to read trim values of Magnetometer of BMX160

[cwi]

As far as I've understood the trim values need to be read from the BMX160 via the mag_if registers.

Following the datasheet:

For a read access:

Write magnetometer register address to read from into Register (0x4D) MAG_IF[1]

Read

Register (0x1B) STATUS

until the bit mag_man_op is “0”

Read Register (0x04-0x0B) DATA_0 to DATA_7, get the data from magnetometer

1. First setting the Powermode: 0x19 -> BMX160_COMMAND_REG_ADDR

2. Set setup mode with burst read 8 bytes: 0x83 -> BMX160_MAG_IF_0_ADDR

3. Write Regaddres too MAG_IF1: BMM150_DIG_Z4_LSB -> BMX160_MAG_IF_1_ADDR

wait 10 ms

4. Read Status byte and check bit man_mag_op is "0"

5. Read Register (0x04-0x0B) DATA_0 to DATA_7, get the data from magnetometer

But I am always getting zeros and not data.

Help is apreciated.

Best regrads,

Constantin

[Jet]

Hi Sir:

     I think first you should check PMU_STATUS(0X03)  to know mag_if_pmu_status. 

     BMX160 is regared BMI160 and BMM150 integration.

     There is only a different CHIP_ID between BMX160 and BMI160+BMM150.

     If want to get mag data, you need to open BMI160 aux interface and BMM150 POWER_CNTRL_ENABLE.

     Ragarding operating BMM150 which is in BMX160 as a Magnetometer, you can reference the follow link:

     https://github.com/BoschSensortec/BMI160_driver