Device bmi270@68 is not ready when using nrf5340 and the BMI270 sample

RE: Device bmi270@68 is not ready when using nrf5340 and the BMI270 sample

Luis Santos — Wed, 21 May 2025 12:05:14 GMT

Hello Joao,

What is mean?

Cold you please share your code and .dts?

RE: Device bmi270@68 is not ready when using nrf5340 and the BMI270 sample

Joao Colombari — Wed, 19 Feb 2025 19:06:53 GMT

Nevermind, now it works fine.

I was just using:

zephyr,deferred-init;

and not initializing in main.

All the best!

RE: Device bmi270@68 is not ready when using nrf5340 and the BMI270 sample

Joao Colombari — Wed, 19 Feb 2025 18:44:47 GMT

Facing the same problem here...

Could you share your project??

Thanks a lot!

RE: Device bmi270@68 is not ready when using nrf5340 and the BMI270 sample

lcj — Fri, 06 Sep 2024 14:11:22 GMT

Got it working thanks to the debug statements! I appreciate your help.

&i2c3 {
	compatible = "nordic,nrf-twim";
	status = "okay";
	pinctrl-0 = <&i2c3_my_default>;
	pinctrl-1 = <&i2c3_my_sleep>;
	pinctrl-names = "default", "sleep";
	zephyr,concat-buf-size = <257>;
    bmi270@68 {
            compatible = "bosch,bmi270";
            reg = <0x68>;
    };	
};

RE: Device bmi270@68 is not ready when using nrf5340 and the BMI270 sample

lcj — Fri, 06 Sep 2024 14:05:03 GMT

With the logging:

Device bmi270@68 is not ready
[00:00:00.257,202] <dbg> bmi270: write_config_file: writing config file max_fifo
[00:00:00.258,880] <err> i2c_nrfx_twim: Need to use the internal driver buffer but its size is insufficient (1 + 256 > 128). Adjust the zephyr,concat-buf-size or zephyr,flash-buf-max-size property (the one with greater value) in the "i2c@c000" node.
[00:00:00.260,528] <err> i2c_nrfx_twim: Need to use the internal driver buffer but its size is insufficient (1 + 256 > 128). Adjust the zephyr,concat-buf-size or zephyr,flash-buf-max-size property (the one with greater value) in the "i2c@c000" node.
*** Booting nRF Connect SDK v3.5.99-ncs1-1 ***

I'm also curious how this works without specifying INT1 and INT2 anywhere.

RE: Device bmi270@68 is not ready when using nrf5340 and the BMI270 sample

Håkon Alseth — Fri, 06 Sep 2024 14:02:03 GMT

Hi,

The initial steps when adding sensors is to ensure that the communication is up and running, and also check that the sensor is ACKing the messages that comes across.

You can add these to your prj.conf for more verbose printing:

CONFIG_LOG=y
CONFIG_SENSOR_LOG_LEVEL_DBG=y
CONFIG_I2C_LOG_LEVEL_DBG=y

However, if there is no ACK on the I2C lines, you will only get the prompt "Device bmi270@68 is not ready".

Kind regards,

Håkon

RE: Device bmi270@68 is not ready when using nrf5340 and the BMI270 sample

lcj — Fri, 06 Sep 2024 13:35:59 GMT

I'm not great with the logic analyzer but can try. Would others be having the same problem with the communication?

RE: Device bmi270@68 is not ready when using nrf5340 and the BMI270 sample

Håkon Alseth — Fri, 06 Sep 2024 13:14:00 GMT

Hi,

Could you scope your SDA/SCL lines to see where the communication fails?

Kind regards,

Håkon

RE: Device bmi270@68 is not ready when using nrf5340 and the BMI270 sample

lcj — Fri, 06 Sep 2024 12:49:19 GMT

I have a board to connect w/the nRF5340 DK with a separate I2C SCL/SDA (currently P0.24 and P0.23 respectively). For the BMI270 INT1 is P0.06 and INT2 is P0.09.

I replaced the overlay with what you provided but got the same response.

I did have to add one additional item because there is a SAO address bit for the BMI and I need to make this MCU GPIO Output LOW and it will be BMI270 default i2c address 0b1101000 (0x68).

&gpio0 {
    status = "okay";
    p0_19_hog: p0_19_hog {
        gpio-hog;
        gpios = <19 GPIO_ACTIVE_HIGH>;
        output-low;
    };
};

RE: Device bmi270@68 is not ready when using nrf5340 and the BMI270 sample

Håkon Alseth — Fri, 06 Sep 2024 11:53:03 GMT

Hi,

Do you have external pull resistors?

If not, try to enable internal pull-ups in DT:

&pinctrl {
	i2c1_my_default: i2c1_my_default {
		group1 {
			psels = <NRF_PSEL(TWIM_SDA, 1, 2)>,
				<NRF_PSEL(TWIM_SCL, 1, 3)>;
            bias-pull-up;
		};
	};

	i2c1_my_sleep: i2c1_my_sleep {
		group1 {
			psels = <NRF_PSEL(TWIM_SDA, 1, 2)>,
				<NRF_PSEL(TWIM_SCL, 1, 3)>;
			low-power-enable;
		};
	};
};

&i2c1 {
	compatible = "nordic,nrf-twim";
	status = "okay";
	pinctrl-0 = <&i2c1_my_default>;
	pinctrl-1 = <&i2c1_my_sleep>;
	pinctrl-names = "default", "sleep";
	zephyr,concat-buf-size = <128>;
    bmi270@68 {
            compatible = "bosch,bmi270";
            reg = <0x68>;
    };	
};

Kind regards,

Håkon