HOW TO IMPLEMENT I2C WITH NRF PRODUCT

[overflow]

Hello, I have an aht20 sensor from adafruit and an rtc ds3221, the 2 sensors are i2c, except that I am taking this course academy.nordicsemi.com/.../, but the course in question they used a shield for i2c communication, already for me I don't think it was the best example,  can you help me? Thanks. 

[overflow]

Hi, I relied on the datasheet of the soc nrf5340, what I can see is that the pins from 0 to 31 of port 0 and 1 can be configured for by the psel register in order to select the sda   and the scl?  I came across this code on github https://github.com/crfosse/ncs_projects/tree/main/peripheral_zephyr/i2c  where it scanned the i2c devices, I configured pins 2 for the sda   and 1 for the scl as you can see in my overlay, but I can't see the devices, I  I'm new, maybe I'm having trouble, I hope I can find a solution, you have the screenshots with the result in terminal.

datasheet

i2c devices scan code

overlay DT

Terminal

[overflow]

I found the solution, thanks to open my eyes, all was in the course. I found the address(0x38) for  the adafruit aht20 TH and I changed  my overlay fil to be like this 

&i2c1 {

    mysensor: mysensor@038{

        compatible = "i2c-device";

        status = "okay";

        reg = < 0x38 >;

    };

};

After that my terminal show this "I2C bus i2c@9000 with address Ox38 is ready!" ;)

[AHaug]

Hi,

Please send a full link and preferably also zip your project if you wish for any input

Kind regards,
Andreas

[overflow]

The link https://github.com/crfosse/ncs_projects/tree/main/peripheral_zephyr/i2c

How can I send my zip project here?

[AHaug]

You can drag your zip into a comment and it will attach 

Or you can use the insert image/video/file function

Kind regards,
Andreas

[overflow]

fund_less6_exer1.zip

This is the zip of the porject

[AHaug]

Hi,

Thank you for supplying that. The part of the code I was interested in looks fine.

Moving on to the next thing. Have you checked the operating conditions of the sensors against the DK you are using? Both of your sensors have a minimal operation voltage (2v and 2.3v) that is higher than what the 7002DK supplies (1.8v), meaning that they are incompatible without modifications (which is also stated in the 7002DK specification).

If you've checked this and done the modifications, can you state what you've done so I can cross examine them?

Kind regards,
Andreas

[overflow]

Hi, 

I connect both sensors on the 5V pin of the DK, or I'm not sure to understand you. 

[AHaug]

Noted, no thats fine. I just wanted to check what you had done.

Are you using the AHT20 module from here https://cdn-learn.adafruit.com/downloads/pdf/adafruit-aht20.pdf, or your own custom board with the sensor https://files.seeedstudio.com/wiki/Grove-AHT20_I2C_Industrial_Grade_Temperature_and_Humidity_Sensor/AHT20-datasheet-2020-4-16.pdf? 

As I stated the 7002DK only supplies 1.8v by default unless you make any modifications. 

VIO_ref will change the voltage on the onboard regulator to what is given in on VIO_ref. This will change the voltage on VDD from 1.8V to the voltage you have on VIO_ref on the nRF5340 + IOVDD on nRF7002

Kind regards,
Andreas

[overflow]

I'm using the AHT20 module from adafruit.

[AHaug]

Noted. 

Let me know if you're able to resolve it by following the suggestions and making sure the voltage is within the operating range of the device and within what the nRF can supply. 

Kind regards,
Andreas

[overflow]

Thank you for your recommendation. 

As indicated in my schematic, it's important to note that I've connected the sensor to the 5V pin, rather than VDD(1.8V). I just verified it with multimeter.