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??

[Jørgen Holmefjord]

Hi,

1. There is API in the library you linked for getting sensor data. What have you done to integrate the library in your application? Did you follow the User Guide?
2. You need to integrate the library in order to get the data first. The data can be sent over BLE using the function ble_nus_data_send().

Best regards,
Jørgen

[Jørgen Holmefjord]

Then you need to post the code you have implemented in order for us to help your any further.

You need to implement the SPI/TWI read/write functions for the library to work. It is just a general library and does not know how to interface with peripherals of nRF5x ICs.

[Sunil vignesh]

I have one doubt while download the code and run. its working fine there is no restart

but while i debug the code without any breakpoints. works fine for a while..

after some time it starts through the error Fatal error in debug terminal

[Sunil vignesh]

i thought

Is this because of sensor which i connected is not properly connect or any bug in the code itself..?

[Jørgen Holmefjord]

There is an error code returned from a function call in your Acc_i2c_Read function. Please compile and run the code as Debug instead of Release mode. Please check which function is returning the error and what error code is returned.

[Sunil vignesh]

it returns 0X05

[Sunil vignesh]

Can I use button 1 to on/off the Bluetooth  is it possible?

The controller can do its work by fetching the data from sensor

if the button is pressed  controller send the respective data to BLE UART otherwise the controller do their work

[Jørgen Holmefjord]

Unless you have very low power requirements, I would recommend that you stay in the connection all the time to make sure there is not a lot of overhead when sending the data. You can then implement a button handler that send the data using ble_nus_data_send when the button is pressed.

[Sunil vignesh]

Actually the fatal error is not constant

1. It was came when I disturb the sensor as same like above return err code 0x01
2. Some other time while I not connect to phone that ble_data_nus_send() returns 0x05 and within few seconds cause fatal error

And definitely I need low power required

Is it possible that whenever I need that time I can able to initialize the ble?.

[Sunil vignesh]

this error happen when i move the sensor fast.

in the above image

rslt is the return err_ode from  BMI init();

rsltr is the return err_code from Acc_i2c_Read();

rsltw from Acc_i2c_Write();

rsltb from ble_nus_data_send();

    rslt = bmi160_init(&sensor);
    APP_ERROR_CHECK(rslt);


  rslt = bmi160_set_sens_conf(&sensor);
    APP_ERROR_CHECK(rslt);
    
    
    int8_t Acc_i2c_Write(uint8_t dev_id, uint8_t reg_addr, uint8_t *reg_data, uint16_t len)
{

    //  NRF_LOG_INFO("WRITE: dev_id: %x reg_addr: %x reg_data: %x len: %i\n", dev_id, reg_addr, *reg_data, 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];
	}
	
	rsltw = nrf_drv_twi_tx(&m_twi, dev_id, data, len + 1, false);
	APP_ERROR_CHECK(rsltw);
        return rsltw;
  
}


int8_t Acc_i2c_Read(uint8_t dev_id, uint8_t reg_addr, uint8_t *reg_data, uint16_t len)
{
	//int8_t rslt = 0;
   //     NRF_LOG_INFO("READ: dev_id: %x reg_addr: %x len: %i\n", dev_id, reg_addr, len);
	rsltr = nrf_drv_twi_tx(&m_twi, dev_id, &reg_addr, 1, true);
        APP_ERROR_CHECK(rsltr);

	if (rsltr == 0)
	{
		rsltr = nrf_drv_twi_rx(&m_twi, dev_id, reg_data, len);
	}
    //    NRF_LOG_INFO("READ: %x",*reg_data);
	return rsltr;
}


      length1 = sprintf(str, "DataX = %5d \n", accel.x);

      rsltb = ble_nus_data_send(&m_nus, str, &length1, m_conn_handle);
     // APP_ERROR_CHECK(rsltb);

[Jørgen Holmefjord]

You should only call ble_nus_data_send when you are in a connection and notifications have been enabled by the central.

[Sunil vignesh]

HI,

I am not able to understand this

Jørgen Holmefjord said:

ou should only call ble_nus_data_send when you are in a connection and notifications have been enabled by the central.

How to enable or disable the notifications by using central

Is there any example?