[BMI160] Register values always zero

[potter1234]

Hi all,

I encountered a strange issue in BMI160 with nordic 52840 mcu. (on a customed board)

The situation looks like this:

1.The mcu has no problem receving irq like STEP_DETECT_INT, DOUBLE_TAP_INT, and the register values of 0x1C-0x1F are correctly displayed.

2. However, when I try to set irqs like LOW_G_INT, HiGH_G_INT, SLOW_NO_MOTION_INT, I can see irqs arriving in my interrupt handler, but the register values of 0x1C-0x1F are always zero.

This can be quite problematic, since I have no clue which interrups are triggered.

for setting low-g interrupt, my code looks like this

struct bmi160_int_settg int_config;

/* Select the Interrupt channel/pin */
int_config.int_channel = BMI160_INT_CHANNEL_1;// Interrupt channel/pin 1

/* Select the Interrupt type */
int_config.int_type = BMI160_ACC_LOW_G_INT;// Choosing LOW G/fall detection interrupt
/* Select the interrupt channel/pin settings */
int_config.int_pin_settg.output_en = BMI160_ENABLE;// Enabling interrupt pins to act as output pin
int_config.int_pin_settg.output_mode = BMI160_DISABLE;// Choosing push-pull mode for interrupt pin
int_config.int_pin_settg.output_type = BMI160_DISABLE;// Choosing active low output
int_config.int_pin_settg.edge_ctrl = BMI160_ENABLE;// Choosing edge triggered output
int_config.int_pin_settg.input_en = BMI160_DISABLE;// Disabling interrupt pin to act as input
int_config.int_pin_settg.latch_dur = BMI160_LATCH_DUR_NONE;// non-latched output

int_config.int_type_cfg.acc_low_g_int.low_data_src=BMI160_ENABLE;//
int_config.int_type_cfg.acc_low_g_int.low_en = BMI160_ENABLE;//
int_config.int_type_cfg.acc_low_g_int.low_mode = BMI160_ENABLE;//
int_config.int_type_cfg.acc_low_g_int.low_hyst = BMI160_ENABLE;//
int_config.int_type_cfg.acc_low_g_int.low_dur = low_dur; // [ms] ((n+1) * 2.5) PREV=50
int_config.int_type_cfg.acc_low_g_int.low_thres = low_thres; // [mg] (n * 7.81) PREV=96

bmi160_set_int_config(&int_config, &sensor); /* sensor is an instance of the structure bmi160_dev */
fall_detected = false;

I'm pretty sure I followed every guideline from here https://github.com/BoschSensortec/BMI160_driver

What could possibly be wrong here?  Is it possible that it has something to do with HW schematic?

Any feedback will be appreciated.

Thank you!

[BSTRobin]

Hello potter1234,

There was another ticket that had same TAP feature usage with you.
You could refer this ticket.
https://community.bosch-sensortec.com/t5/MEMS-sensors-forum/bmi160-tap-detection/td-p/21749

[potter1234]

What I've been struggling has nothing to do with tap at all.

My question is I can see LOW_G_INT, HiGH_G_INT, SLOW_NO_MOTION_INT,  irqs firing, but the register values of 0x1C-0x1F are always zero.

In this case, I can't tell which interrupt is actually firing and I really need to distinguish them.

[BSTRobin]

Hello potter1234,

It was a reference code that run well. When MCU received HW interrupt signal, then read non-zero 0x1C-0x1F register values. For your reference to compare with you code.