BMM350 not updating data after suspend mode

[444]

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]

@BSTRobin
I am using exactly same code without any change.
I am using Renesas MCU  and sensor interfaced as shown in following figure. VCC is having 1.8V

I also tried to put a loop around PMU busy and it seems like it is busy always, never gets free.
loop looks like this

    /* Check PMU busy */
    rslt = bmm350_get_pmu_cmd_status_0(&pmu_cmd_stat_0, &dev);
    bmm350_error_codes_print_result("bmm350_get_pmu_cmd_status_0", rslt);

    printf("Expected : 0x07 : PMU cmd busy : 0x0\n");
    printf("Read : 0x07 : PMU cmd busy : 0x%X\n", pmu_cmd_stat_0.pmu_cmd_busy);


    while(pmu_cmd_stat_0.pmu_cmd_busy != 0){
        /* Check PMU busy */
        rslt = bmm350_get_pmu_cmd_status_0(&pmu_cmd_stat_0, &dev);
        bmm350_error_codes_print_result("bmm350_get_pmu_cmd_status_0", rslt);

        printf("Expected : 0x07 : PMU cmd busy : 0x0\n");
        printf("Read : 0x07 : PMU cmd busy : 0x%X\n", pmu_cmd_stat_0.pmu_cmd_busy);

        R_BSP_SoftwareDelay(100, BSP_DELAY_UNITS_MILLISECONDS);
    }

output looks like this Always,  you can also see my code in the attachment
Expected : 0x07 : PMU cmd busy : 0x0

Read : 0x07 : PMU cmd busy : 0x1
Also I tried to put a loop around error checking which is returning 0xff always!

And I want to know what is the correct way to put sensor in low power mode and read valid values occasionally. It is not clear from the examples.
shold I configure it
1. init -> Normal mode -> suspend mode -> loop [forced mode -> read]
2. init -> Normal mode -> suspend mode -> loop [read ]  --- this is in example , but as you said it is not useful
3. init -> forced mode -> loop[read] -- I tried forced mode example but results are not changing the same as this one, I have attached that logs and code as well.

[444]

@BSTRobin 

I am putting this sensor in Suspend mode and reading it after putting it into forced mode, it seems all the registers have FF
init->normal mode -> suspend mode -> loop [ forced mode -> wait 2s -> read]

[444 · Accepted solution]

The issue is solved by lowering the baud rate on I2C from around 300k to around 100k. 

correct sequence to read in suspend mode is

init -> settings -> suspend mode -> loop [forced mode -> read sensor]
combination 1 in example of forced mode is not following the above mentioned sequence and not producing updated value in each loop.

Thanks a lot for your help @BSTRobin