BMX160 Any Motion Detection and Flat Detection interrupts are always triggered

[Nikosant03]

Hi everyone,

I am trying to map some interrupts on CHANNEL1. I followed the API instructions to configure the interrupts with success. So far I have configured the Any-Motion Detection,  Flat Detection, and the NO-Motion Detection

Regarding the NO-Motion Detection, everything works fine but when I use the Any-Motion Detection & Flat Detection the interrupt they are both always set and never resets. I have experimented with the configuration parameters as well as the acceleration range with no success so far. I have read carefully the manual without being able to find what's going wrong. However, I assume that is something simple.. I checked the registers 0x55-0x57 (INT_MAP), 0x5F-0x62 (INT_MOTION), 0x54 (INT_LATCH) and everything are fine (no latching).

This is the Any-Motion Detection configuration

void anyMotionInterrupt_set() {

  int_config.int_channel = BMI160_INT_CHANNEL_1;   // na - Select the interrupt channel
  int_config.int_type = BMI160_ACC_ANY_MOTION_INT; // na - choosing Any Motion Interrupt

  // na - the following configuration is written to registers (0x53) INT_OUT_CTRL & (0x54) INT_LATCH  see datasheet pg71 section 2.11.20
  int_config.int_pin_settg.output_en = BMI160_ENABLE;         // na - Enabling interrupt pin as output -> register (0x53)
  int_config.int_pin_settg.output_mode = BMI160_DISABLE;      // na - Selecting push-pull mode for interrupt pin -> register (0x53)
  int_config.int_pin_settg.output_type = BMI160_DISABLE;      // na - Setting interrupt pin to active low -> register (0x53)
  int_config.int_pin_settg.edge_ctrl = BMI160_ENABLE;         // na - Enabling edge trigger -> register (0x53)
  int_config.int_pin_settg.input_en = BMI160_DISABLE;         // na - Disabling interrupt pin to act as input -> register (0x54)
  int_config.int_pin_settg.latch_dur = BMI160_LATCH_DUR_NONE; // na - non-latched output -> register (0x54)

  // na - Select the Any Motion Interrupt parameter
  int_config.int_type_cfg.acc_any_motion_int.anymotion_en = BMI160_ENABLE; // na - 1- Enable the any-motion, 0- disable any-motion
  int_config.int_type_cfg.acc_any_motion_int.anymotion_x = BMI160_ENABLE;  // na - Enabling x-axis for any motion interrupt - monitor x axis
  int_config.int_type_cfg.acc_any_motion_int.anymotion_y = BMI160_ENABLE;  // na - Enabling y-axis for any motion interrupt - monitor y axis
  int_config.int_type_cfg.acc_any_motion_int.anymotion_z = BMI160_ENABLE;  // na - Enabling z-axis for any motion interrupt - monitor z axis
  int_config.int_type_cfg.acc_any_motion_int.anymotion_dur = 2;            // na - any-motion duration. This is the consecutive datapoints -> see datasheet pg32 section 2.6.1 <int_anym_dur> and pg78
  int_config.int_type_cfg.acc_any_motion_int.anymotion_thr = 20;           // na - An interrupt will be generated if the absolute value of two consecutive accelarion signal exceeds the threshold value -> see datasheet pg32 section 2.6.1 <int_anym_th> and pg78 INT_MOTION[1]
                                                                           // na - (2-g range) -> (anymotion_thr) * 3.91 mg, (4-g range) -> (anymotion_thr) * 7.81 mg, (8-g range) ->(anymotion_thr) * 15.63 mg, (16-g range) -> (anymotion_thr) * 31.25 mg

  rslt = bmi160_set_int_config(&int_config, &sensor); // na - Set Any-motion interrupt
  NRF_LOG_INFO("rslt: %d", rslt);

  if (rslt != BMI160_OK) {
    NRF_LOG_INFO("BMI160 Any-motion interrupt configuration failure!\n");
  } else {
    NRF_LOG_INFO("BMI160 Any-motion interrupt configuration done!\n");
  }
}

This is the Flat Detection configuration

void flatInterrupt_set() {

  /* 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_FLAT_INT; // Choosing flat 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

  /* Select the Flat interrupt parameters */
  int_config.int_type_cfg.acc_flat_int.flat_en = BMI160_DISABLE; // 1-enable, 0-disable the flat interrupt
  int_config.int_type_cfg.acc_flat_int.flat_theta = 8;          // threshold for detection of flat position in range from 0° to 44.8°.
  int_config.int_type_cfg.acc_flat_int.flat_hy = 1;             // Flat hysteresis
  int_config.int_type_cfg.acc_flat_int.flat_hold_time = 1;      // Flat hold time (0 -> 0 ms, 1 -> 640 ms, 2 -> 1280 ms, 3 -> 2560 ms) - delay time for which the flat value must remain stable for the flat interrupt to be generated (datasheet pg82)

  /* Set the Flat interrupt */
  rslt = bmi160_set_int_config(&int_config, &sensor); /* sensor is an instance of the structure bmi160_dev */

  if (rslt != BMI160_OK) {
    NRF_LOG_INFO("BMI160 flat interrupt configuration failure!\n");
  } else {
    NRF_LOG_INFO("BMI160 flat interrupt configuration done!\n");
  }
}

This is accel/gyro/mag configuration

// na - configure Accel sensor
  sensor.accel_cfg.odr = BMI160_ACCEL_ODR_100HZ;     // na - output data rate - Configure accel to measure at 100Hz
  sensor.accel_cfg.range = BMI160_ACCEL_RANGE_2G;    // na - range
  sensor.accel_cfg.bw = BMI160_ACCEL_BW_NORMAL_AVG4; // na - bandwidth
  sensor.accel_cfg.power = BMI160_ACCEL_NORMAL_MODE; // na - powermode

  // na - configure Gyro sensor
  sensor.gyro_cfg.odr = BMI160_GYRO_ODR_100HZ;       // na - output data rate - Configure gyro to measure at 100Hz
  sensor.gyro_cfg.range = BMI160_GYRO_RANGE_500_DPS; // na - range
  sensor.gyro_cfg.bw = BMI160_GYRO_BW_NORMAL_MODE;   // na - bandwidth
  sensor.gyro_cfg.power = BMI160_GYRO_NORMAL_MODE;   // na - powermode

  rslt = bmi160_set_sens_conf(&sensor); // na - configures the power mode, range and bandwidth of sensors
  APP_ERROR_CHECK(rslt);

  bmm150.settings.preset_mode = BMM150_PRESETMODE_REGULAR; //BMM150_PRESETMODE_LOWPOWER; // // na - Presetmode of sensor - Datasheet page 19
  rslt = bmm150_set_presetmode(&bmm150);                   // na - set the preset mode of the sensor
  APP_ERROR_CHECK(rslt);

  bmm150.settings.pwr_mode = BMM150_NORMAL_MODE; //BMM150_FORCED_MODE;
  rslt = bmm150_set_op_mode(&bmm150);            //
  APP_ERROR_CHECK(rslt);

  // Set the polling rate (Hz). Is the output data rate
  sensor.aux_cfg.aux_odr = BMI160_AUX_ODR_100HZ; // na - Configure accel to measure at 100Hz. See the table on page 67 of the datasheet. 8 = 100Hz , 6 = 25Hz see the formula on pg67 of the datasheet
  bmi160_config_aux_mode(&sensor);
  bmi160_set_aux_auto_mode(&aux_addr, &sensor); // na - Set the auxiliary sensor to auto mode

Any advice from the experts?

Thanks in advance

Nick

[FAE_CA1]

Hi,

Thanks for your inquiry.

Please try to change BMM150 to forced mode from normal mode and ODR to 25Hz from 100Hz. When you test both any-motion and flat interrupt, please make sure BMI160 is tilted and stationary. Then INT1 pin signal should be low. When you tap BMI160, INT1 should show a pulse. When you put your device flat, then the flat interrupt will show a pulse on INT1 pin.

Please let us know which country you are located. Our local FAE will support you further.

Thanks.

[Nikosant03]

Thank you for your answer  FAE_CA1

I will try your suggestion and I will return with feedback.

I am located in Cyprus

 is there a FAE for this region?

[Nikosant03]

Hi  FAE_CA1

I've changed the mode to forced and ODR to 25Hz but still the INT1 pin is always low either when the sensor is flat of tilted.

[FAE_CA1]

Hi,

Sorry that we don't have FAE covering Cyprus. Please try to enable any-motion interrrupt only to see if you can get it to work. Then you can enable flat interrupt only.

Please see the attached "How to generate single-tap and double-tap interrupt using BMI160 accelerometer.pdf" as a reference. You need to set BMI160 interrupt as push-pull and active high.

Also please see the attached "How to use BMA253 flat interrupt in low power mode v1.1.pdf" as a reference about how flat interrupt works.

Thanks.