I2C burst write for nRF5340 fails

RE: I2C burst write for nRF5340 fails

Albrecht Markus Schellenberger — Wed, 16 Jun 2021 08:16:13 GMT

Thanks for the feedback, Samuel! I’m glad to hear that this solved the issue.

Cheers!

Markus

RE: I2C burst write for nRF5340 fails

SamA — Wed, 16 Jun 2021 05:53:02 GMT

Sorry for reporting back late.. the concat-buf-size = <128>; worked. I had to tune it to fit my array size.

RE: I2C burst write for nRF5340 fails

SamA — Fri, 21 May 2021 01:50:13 GMT

Great, will experiment more. ! thanks

RE: I2C burst write for nRF5340 fails

Albrecht Markus Schellenberger — Thu, 20 May 2021 11:11:38 GMT

Hello Samuel,

one difference between those two devices is that the nRF5340 is using TWIM drivers while the nRF52840 is using TWI drivers. TWIM has a hardware limitation which results in burst writes not all sensors are supporting. You can read more about this here. There is also a similar case in DevZone.

A good starting point could be to add the concat-buf-size attribute in an overlay file and check if that makes any differences. Below you can see an example of the attribute usage:

/*
 * Copyright (c) 2021 Bosch Sensortec GmbH
 *
 * SPDX-License-Identifier: Apache-2.0
 */
&arduino_i2c {
    status = "okay";
    zephyr,concat-buf-size = <128>;
    bmi270@68 {
        compatible = "bosch,bmi270";
        reg = <0x68>;
        label = "BMI270";
    };
};

I hope this will help you!

Regards,

Markus

RE: I2C burst write for nRF5340 fails

SamA — Thu, 20 May 2021 02:44:05 GMT

https://devzone.nordicsemi.com/f/nordic-q-a/56253/nrf5340-unable-to-write-with-i2c_1-in-zephyr

This seems to be related

RE: I2C burst write for nRF5340 fails

SamA — Thu, 20 May 2021 02:36:05 GMT

Using latest NCS 1.5.99, the default SES. Latest Zephyr for the BMI270 code. (Which worked on NRF52840 when I generated it for that board type).

Seem to see others having trouble also from the forum.

RE: I2C burst write for nRF5340 fails

Albrecht Markus Schellenberger — Tue, 18 May 2021 12:58:34 GMT

Hello Samuel,

again, my apologies for the late reply.

What kind of toolchain and which version of it are you using? I see that you have tagged the nRF5 SDK, but it does not support the nRF5340.

Regards,

Markus

RE: I2C burst write for nRF5340 fails

Albrecht Markus Schellenberger — Fri, 14 May 2021 14:25:52 GMT

Hello Samuel,

Due to public holidays in Norway, we are short on staff at the moment. I might need some time to analyse your case, but I will come back to you as soon as possible.

I apologise for any inconvenience caused.

Regards,

Markus