Configure i2c

[Boggibill]

I have a quick question about configure i2c.

I have the following schematic:

And the following configuration for the nrf54l15:

&pinctrl {
i2c20_default: i2c20_default {
group1 {
psels = <NRF_PSEL(TWIM_SCL, 2, 1)>, <NRF_PSEL(TWIM_SDA, 2, 3)>;
bias-pull-up;
};
};
i2c20_sleep: i2c20_sleep {
group1 {
psels = <NRF_PSEL(TWIM_SCL, 2, 1)>, <NRF_PSEL(TWIM_SDA, 2, 3)>;
low-power-enable;
};
};
};

&i2c20 {
status = "okay";
clock-frequency = <I2C_BITRATE_STANDARD>;
pinctrl-0 = <&i2c20_default>;
pinctrl-1 = <&i2c20_sleep>;
pinctrl-names = "default", "sleep";

aht20@38 {
compatible = "aosong,aht20";
reg = <0x38>;
label = "AHT20";
};
};

And the following in prj.conf:

CONFIG_I2C=y

CONFIG_SENSOR=y

CONFIG_DHT20=y

Question:

Is this the correct configuration for getting i2c communication up and running? Im trying to scan for i2c adresses, but can't find anything.

Or is there a problem using p2.01 and p2.03 for i2c communication?

[Einar Thorsrud]

Hi Pål,

There are no TWI instances for GPIP port P2, so you need to pick different GPIO pins. See Configuration. Note that you also need to make sure that SCL is on a clock pin (that is the case with P2.01, but aas mentionned P2 cannot be used).

PS: As menionned under Cross power-domain use you can use P2 for TWI when using constant latency mode, but this is not suitable for a low power product.

Br,

Einar

[Boggibill]

Ok.

I see, thanks for the quick response.

So if I use P0.02 (SDA) and P0.03 (SCL), I should see better results?

[Einar Thorsrud]

Yes, that should be OK. As this is GPIO port P0, you need to use TWIM30 in that case.