How to Interface nRF5340 DK with Adafruit 9-DOF Absolute Orientation IMU Fusion Breakout - BNO055 sensor.

[KarthikKumar]

Hi,

I'm trying to interface Adafruit 9-DOF Absolute Orientation IMU Fusion Breakout - BNO055 sensor with nRF5340 DK board. Can you please help with the code where I want to print all the sensed data on the terminal via a Bluetooth connection.

Currently I'm working on peripheral uart and central uart example, can you suggest me how can I include the code in peripheral uart which is the BNO055 sensor code?

Regards

Karthik Kumar

[Kenneth]

Hi, you should start out with an I2C sample from the SDK, to see how it works, and then do the necessary modifications to support the BNO055.

For Zephyr, you can probably start with one of the sensor applications that uses I2C: http://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/zephyr/samples/sensor/sensor.html

Best regards,
Kenneth

[KarthikKumar]

Hi Kenneth,

Can you guide me which example in specific to be explored.

Regards

Karthik Kumar

[KarthikKumar]

Thank you

[KarthikKumar]

Hi Kenneth,

Not able to find the i2c connection on the code? can you help me.

Regards

Karthik Kumar

[Kenneth]

The example here: https://github.com/nrfconnect/sdk-zephyr/blob/main/samples/sensor/bmi270/src/main.c 
The driver here: https://github.com/nrfconnect/sdk-zephyr/blob/main/drivers/sensor/bmi270/bmi270.c 

You can find that the drivers have two api calls to read and write to the sensor: reg_read() and reg_write().

Best regards,
Kenneth

[KarthikKumar]

So on that point, which program should i modify and how are these two related to each other. Finally which programme should be flashed on the board

[Kenneth]

You will mainly need to modify the driver to fit your new sensor, in other words you will need to change the implementation of the exposed api functions to fit your new sensor and change the name of the api functions to fit your new sensor:

static const struct sensor_driver_api bmi270_driver_api = {
	.sample_fetch = bmi270_sample_fetch,
	.channel_get = bmi270_channel_get,
	.attr_set = bmi270_attr_set
};

[KarthikKumar]

In that case i need to replace the whole code in bmi270.c with my new sensor name and also update the registers in bmi270.h and bmi270_config_file.h too?

or just change in the part of code you have mentioned?

[KarthikKumar]

Hi Kenneth,

I found and interface for adafruit board on githiub,

https://github.com/adafruit/Adafruit_BNO055

How can I import this on the nordic SDK, and then flash it on the board. I'm using Visual Studio Code for this purpose.

Can you guide me with the  all the steps that is involved in importing that from github into the nordic sdk.

Regards

Karthik Kumar

[KarthikKumar]

Hi Kenneth,

I tried to modify the code also added an overlay file too, but its not working. Can you help me.

&i2c1 {
    compatible = "nordic,nrf-twim";
	status = "okay";
	sda-pin = < 30 >;
	scl-pin = < 31 >;
    clock-frequency = <I2C_BITRATE_STANDARD>;  
	
	/* The I2C address could be one of two, here 0x76 is assumed */
	bmi270@28 {
		compatible = "bosch,bmi270";
		reg = <0x28>;
		label = "BNO055";
	};
};

Regards

Karthik Kumar

[Kenneth]

I recommend to get an logic analyzer trace to check if there is data on the I2C interface, and if the slave is acking the data.

Kenneth

[KarthikKumar]

I tried that but there is no data. 

Can I use the Arduino code on nordic?

https://github.com/arduino-libraries/BNO055