Solved: BMM350 not updating data after suspend mode

444 · ‎03-11-2024

I have been using BMM350. I am initialising it using APIs from the library and setting power mode suspend and then when I put it in forced mode and see data , it returns me same data all the time ? what can be the problem ?

following is my code.

if I do not put sensor in suspend mode , it runs ok! @BSTRobin
--------

bmm350_init(&dev);/* Initialize BMM350 */

/* Set ODR and performance */
bmm350_set_odr_performance(BMM350_DATA_RATE_1_5625HZ, BMM350_NO_AVERAGING, &dev);

/* Enable all axis */
rslt = bmm350_enable_axes(BMM350_X_EN, BMM350_Y_EN, BMM350_Z_EN, &dev);

rslt = bmm350_set_powermode(BMM350_NORMAL_MODE, &dev);

rslt = bmm350_delay_us(10000, &dev);

rslt = bmm350_get_compensated_mag_xyz_temp_data(&mag_temp_data, &dev);

bmm350_set_powermode(BMM350_SUSPEND_MODE,&dev); // power saving while not in use
while (1){
bmm350_set_powermode(BMM350_FORCED_MODE,&dev); // power saving while not in use

bmm350_get_compensated_mag_xyz_temp_data(&mag_temp_data, &dev);
delay(1000);
}

I can not see updated data if sensor is not sampling at ODR rate as can be seen in the following picture. Only when I see periodic current consumption at ODR rate I see updated data. The time between two current peak is around 663 ms which is inverse of 1.5625 Hz.

444 · ‎03-15-2024

I run the example project
https://github.com/boschsensortec/BMM350_SensorAPI/tree/main/examples/bmm350_config_changes

and the results are same, the sensor is not updating data in suspend mode

444 · ‎03-15-2024

This is the full out put of example one , one thing I can not understand is error is always 1 instead of 0 , I have tried two different sensor and the results are same

Expected : 0x07 : PMU cmd busy : 0x0

Read : 0x07 : PMU cmd busy : 0x1

Expected : 0x02 : Error Register : 0x0

Read : 0x02 : Error Register : 0xFF

Expected : 0x2E : Interrupt control : 0x86

Read : 0x2E : Interrupt control : 0x86

Data ready enabled\r

Compensated Magnetometer and temperature data in NORMAL MODE

Timestamp(ms), Mag_X(uT), Mag_Y(uT), Mag_Z(uT), Temperature(degC)

-1.078575, -1.078646, -1.080269, 25.239235

***** AVERAGE MAG VALUE *****

Average_Mag_X(uT), Average_Mag_Y(uT), Average_Mag_Z(uT)

-0.539288, -0.539323, -0.540135

Compensated Magnetometer and temperature data in SUSPEND MODE

Timestamp(ms), Mag_X(uT), Mag_Y(uT), Mag_Z(uT), Temperature(degC)

-1.078575, -1.078646, -1.080269, 25.239235

Compensated Magnetometer and temperature data in NORMAL MODE

Disable x and y axis, enable z axis

Mag_X(uT), Mag_Y(uT), Mag_Z(uT), Temperature(degC)

0.000000, 0.000000, -1.080252, 25.239235

nopsee this stuff --printsee this stuff --++printfnopsee this stuff --printsee this stuff --++printfnop -1.078575, -1.078646, -1.080269, 25.239235

-1.078575, -1.078646, -1.080269, 25.239235

***** AVERAGE MAG VALUE *****

Average_Mag_X(uT), Average_Mag_Y(uT), Average_Mag_Z(uT)

-0.539288, -0.539323, -0.540135

Noise level x, Noise level y, Noise level z

0.539288, 0.539323, 0.540135

Compensated Magnetometer and temperature data in SUSPEND MODE

Timestamp(ms), Mag_X(uT), Mag_Y(uT), Mag_Z(uT), Temperature(degC)

-1.078575, -1.078646, -1.080269, 25.239235

Compensated Magnetometer and temperature data in NORMAL MODE

Disable x and y axis, enable z axis

Mag_X(uT), Mag_Y(uT), Mag_Z(uT), Temperature(degC)

0.000000, 0.000000, -1.080252, 25.239235

444 · ‎03-15-2024

The full response of example 1 looks like this @BSTRobin

I have tried to run this example on 2 different sensors and error returns 0xFF all the time? What can be the reason
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Expected : 0x07 : PMU cmd busy : 0x0

Read : 0x07 : PMU cmd busy : 0x1

Expected : 0x02 : Error Register : 0x0

Read : 0x02 : Error Register : 0xFF

Expected : 0x2E : Interrupt control : 0x86

Read : 0x2E : Interrupt control : 0x86

Data ready enabled\r

Compensated Magnetometer and temperature data in NORMAL MODE

Timestamp(ms), Mag_X(uT), Mag_Y(uT), Mag_Z(uT), Temperature(degC)

-1.078575, -1.078646, -1.080269, 25.239235

***** AVERAGE MAG VALUE *****

Average_Mag_X(uT), Average_Mag_Y(uT), Average_Mag_Z(uT)

-0.539288, -0.539323, -0.540135

Compensated Magnetometer and temperature data in SUSPEND MODE

Timestamp(ms), Mag_X(uT), Mag_Y(uT), Mag_Z(uT), Temperature(degC)

-1.078575, -1.078646, -1.080269, 25.239235

Compensated Magnetometer and temperature data in NORMAL MODE

Disable x and y axis, enable z axis

Mag_X(uT), Mag_Y(uT), Mag_Z(uT), Temperature(degC)

0.000000, 0.000000, -1.080252, 25.239235

nopsee this stuff --printsee this stuff --++printfnopsee this stuff --printsee this stuff --++printfnop -1.078575, -1.078646, -1.080269, 25.239235

-1.078575, -1.078646, -1.080269, 25.239235

***** AVERAGE MAG VALUE *****

Average_Mag_X(uT), Average_Mag_Y(uT), Average_Mag_Z(uT)

-0.539288, -0.539323, -0.540135

Noise level x, Noise level y, Noise level z

0.539288, 0.539323, 0.540135

Compensated Magnetometer and temperature data in SUSPEND MODE

Timestamp(ms), Mag_X(uT), Mag_Y(uT), Mag_Z(uT), Temperature(degC)

-1.078575, -1.078646, -1.080269, 25.239235

Compensated Magnetometer and temperature data in NORMAL MODE

Disable x and y axis, enable z axis

Mag_X(uT), Mag_Y(uT), Mag_Z(uT), Temperature(degC)

0.000000, 0.000000, -1.080252, 25.239235

BSTRobin · ‎03-19-2024

Hi 444,

It is normal that the sensor is not updating data in suspend mode. As you can see it from BMM350 data sheet, data conversion does not occur in suspend mode, but you can read the register value of the sensor.

See it from your log data:
1.PMU cmd busy : 0x1
Error Register : 0xFF
pmu_cmd_busy means the previous MU CMD is still in processing.

2.In normal mode, the value of the sensor in your log is also the same. We would like to know:

We would like to know what kind of hardware are you using? And did you strictly refer to official example code?
I have attached the log of my usage example code(https://github.com/boschsensortec/BMM350_SensorAPI/blob/main/examples/bmm350_config_changes/bmm350_c...), which shows the hardware usage of application board 3.0+BMM350 shutter board 3.0.

BMM350 not updating data after suspend mode

BMM350 not updating data after suspend mode

Still looking for something?