BMI160 + NRF52832 + I2C

[Sunil vignesh]

HI,

I want to develop a program to access Accelerometer and gyroscope value from BMI160 sensor. I have used this BMI160 library 

I alter the TWI_SENSOR code and it works for self testing ACC code. but i need to calibrate the x, y, z axis value and i want to add BLE stack to read in mobile app.

1. How to collect all the X,Y,Z axis value

2. i need to see the LOGS in Bluetooth app by using BLE_UART. how to edit the BLE_UART code to get the respective ACC and GYRO value in BLE APP.

Is there any code for reading X,Y,Z axis for BMI160??

[Sunil vignesh]

HI,

I am trying to get the Accel X value and gyro X value but the rslt is 0 and data also 0.

#include <stdio.h>
#include "boards.h"
#include "app_util_platform.h"
#include "app_error.h"
#include "nrf_drv_twi.h"
#include "nrf_delay.h"

/* Sensor */
#include "bmi160.h"

#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#include "nrf_log_default_backends.h"



/* TWI instance ID. */
#define TWI_INSTANCE_ID     0

/* Indicates if operation on TWI has ended. */
static volatile bool m_xfer_done = false;

/* TWI instance. */
static const nrf_drv_twi_t m_twi = NRF_DRV_TWI_INSTANCE(TWI_INSTANCE_ID);
struct bmi160_dev sensor;

int8_t rslt = BMI160_OK;
struct bmi160_sensor_data accel;
struct bmi160_sensor_data gyro;
//struct bmi160_sensor_data.gyro Gyro;

int8_t Acc_i2c_Write(uint8_t dev_id, uint8_t reg_addr, uint8_t *reg_data, uint16_t len)
{
	int8_t rslt = 0;
	uint8_t data[len + 1];
	data[0] = reg_addr;
	for (uint16_t i = 0; i < len; i++) {
		data[i + 1] = reg_data[i];
	}
	
	rslt = nrf_drv_twi_tx(&m_twi, dev_id, data, len + 1, false);
	return rslt;
}


int8_t Acc_i2c_Read(uint8_t dev_id, uint8_t reg_addr, uint8_t *reg_data, uint16_t len)
{
	int8_t rslt = 0;

	rslt = nrf_drv_twi_tx(&m_twi, dev_id, &reg_addr, 1, false);
	nrf_delay_ms(5);
	if (rslt == 0)
	{
		rslt = nrf_drv_twi_rx(&m_twi, dev_id, reg_data, len);
	}
	
	return rslt;
}

void Acc_delay_ms(uint32_t period)
{ 
	// delay time
	
  nrf_delay_ms( period ) ;
} // user_delay_ms()

void twi_init (void)
{
    ret_code_t err_code;

    const nrf_drv_twi_config_t twi_config = {
       .scl                = ARDUINO_SCL_PIN,
       .sda                = ARDUINO_SDA_PIN,
       .frequency          = NRF_DRV_TWI_FREQ_100K,
       .interrupt_priority = APP_IRQ_PRIORITY_HIGH,
       .clear_bus_init     = false
    };

    err_code = nrf_drv_twi_init(&m_twi, &twi_config, NULL, NULL);
    APP_ERROR_CHECK(err_code);

    nrf_drv_twi_enable(&m_twi);
}

void Acc_Gyro_config(void)
{
/* Select the Output data rate, range of accelerometer sensor */
    sensor.accel_cfg.odr = BMI160_ACCEL_ODR_1600HZ;
    sensor.accel_cfg.range = BMI160_ACCEL_RANGE_2G;
    sensor.accel_cfg.bw = BMI160_ACCEL_BW_NORMAL_AVG4;

    /* Select the power mode of accelerometer sensor */
    sensor.accel_cfg.power = BMI160_ACCEL_NORMAL_MODE;

    /* Select the Output data rate, range of Gyroscope sensor */
    sensor.gyro_cfg.odr = BMI160_GYRO_ODR_3200HZ;
    sensor.gyro_cfg.range = BMI160_GYRO_RANGE_2000_DPS;
    sensor.gyro_cfg.bw = BMI160_GYRO_BW_NORMAL_MODE;

    /* Select the power mode of Gyroscope sensor */
    sensor.gyro_cfg.power = BMI160_GYRO_NORMAL_MODE; 

    /* Set the sensor configuration */

    rslt = bmi160_set_sens_conf(&sensor);

    if(rslt == BMI160_OK){
    NRF_LOG_INFO("sensor Configured... \n");
    } else {
   NRF_LOG_INFO("sensor not Configured... \n");
    }
   
    NRF_LOG_FLUSH();
}
void Acc_Gyro_self_test(void)
{
  rslt = bmi160_perform_self_test(BMI160_ACCEL_ONLY, &sensor);
 
          
          if (rslt == BMI160_OK) {
                  NRF_LOG_INFO("ACCEL SELF TEST RESULT SUCCESS \n");
          } else {
                  NRF_LOG_INFO("ACCEL SELF TEST RESULT FAIL\n");
          }NRF_LOG_FLUSH();
  
  rslt = bmi160_perform_self_test(BMI160_GYRO_ONLY, &sensor);
  
          
          if (rslt == BMI160_OK) {
                  NRF_LOG_INFO("gyro SELF TEST RESULT SUCCESS \n");
          } else {
                  NRF_LOG_INFO("gyro SELF TEST RESULT FAIL \n");
          }

      NRF_LOG_FLUSH();
}


void BMI_mode(void)
{ 
  
    sensor.id = BMI160_I2C_ADDR;
    sensor.interface = BMI160_I2C_INTF;
    sensor.read = Acc_i2c_Read;
    sensor.write = Acc_i2c_Write;
    sensor.delay_ms = Acc_delay_ms;

    rslt = bmi160_init(&sensor);
    if(rslt == BMI160_OK){
    NRF_LOG_INFO("BMI160 Initialized... \n");
    } else {
    NRF_LOG_INFO("BMI160 not Initialized... \n");
    }
    NRF_LOG_FLUSH();
}
 
 int main(void)
 {
  bsp_board_init(BSP_INIT_LEDS);
    APP_ERROR_CHECK(NRF_LOG_INIT(NULL));
    NRF_LOG_DEFAULT_BACKENDS_INIT();

    NRF_LOG_INFO("BMI160 get started.\n");
    NRF_LOG_FLUSH();
    Acc_delay_ms(1000);
    twi_init();
    Acc_delay_ms(300);
    BMI_mode();
    Acc_delay_ms(300);
    Acc_Gyro_config();
    Acc_delay_ms(300);
    Acc_Gyro_self_test();
    Acc_delay_ms(300);
    bmi160_get_sensor_data(BMI160_ACCEL_SEL, &accel, NULL, &sensor);
    NRF_LOG_INFO("x is %ld \r\n",accel.x);// accelerometer x value

    rslt = bmi160_get_sensor_data(BMI160_GYRO_SEL, NULL, &gyro, &sensor);
	
	NRF_LOG_INFO("rslt:%d, data: %d", rslt,gyro.x); // gyroscope x value
    NRF_LOG_FLUSH();

 }

[Jørgen Holmefjord]

Most likely there is some error in your TWI read function. From the datasheet, it looks like the I2C read operation does not expect a stop condition between TX and RX. Try changing the no_stop parameter of nrf_drv_twi_tx() in Acc_i2c_Read() to true instead of false.

[Sunil vignesh]

Even though it won't works.  

i got link as similar error obtain but here i don't know how to apply here is the link

https://github.com/BoschSensortec/BMI160_driver/issues/44

in that at last it says : " I got the data from the BMI160 by enable the chip with CS. However, When I integrate the code with the BLE-uart, I kept getting zero with the right configuration..."

[Jørgen Holmefjord]

Have you checked the TWI lines with a logic analyzer to see if any data is transmitted/received?

[Sunil vignesh]

No, i didn't check that. but with rslt return data only. i checked