nRF54L15 DK I2C and SPI Pins

RE: nRF54L15 DK I2C and SPI Pins

Oskar Klockar — Fri, 08 May 2026 16:09:03 GMT

Hei, I am trying to understand which pins could be used for I2C in my hardware design. According to the following article, section Registers > Configuration, only GPIO ports P0 and P1 are listed for TWIM, but not P2:
https://docs.nordicsemi.com/bundle/ps_nrf54L15/page/twim.html#d1697e783

Edvin Your following statement therefore confuses me:

[quote userid="26071" url="~/f/nordic-q-a/120228/nrf54l15-dk-i2c-and-spi-pins/529398"]if you need to use the higher speeds for TWI, then you can use the "dedicated pins on P2".[/quote]

Could it be that P2 is not mentioned since it would be "overkill", especially if used for I2C with maximum 400 kbps?
Best regards,
Oskar

RE: nRF54L15 DK I2C and SPI Pins

Håkon Alseth — Tue, 22 Apr 2025 07:27:55 GMT

Hi,

Please see the restrictions given depending on what instance you use for each function:

https://docs.nordicsemi.com/bundle/ps_nrf54L15/page/spim.html#d1550e772

https://docs.nordicsemi.com/bundle/ps_nrf54L15/page/twim.html#d1820e690

https://docs.nordicsemi.com/bundle/ps_nrf54L15/page/uarte.html#d1900e814

[quote user="Theja"]Interrupt pins - 2 pins
[/quote]

You need to be aware that P2 cannot do pin interrupt. P0 and P1 ports can do that.

Kind regards,

Håkon

RE: nRF54L15 DK I2C and SPI Pins

Theja — Tue, 22 Apr 2025 07:23:50 GMT

Hi,

If we want make our coustom board can you kindly suggest pins for below peripherals,

SPI- CLK, MISO, MOSI, CS.
I2C - SCL, SDA.
UART - Tx, Rx.
Interrupt pins - 2 pins

RE: nRF54L15 DK I2C and SPI Pins

Håkon Alseth — Tue, 01 Apr 2025 12:44:00 GMT

Hi,

The former answer lists and links the pins that can be used, regardless of it being a DK or a custom board.

Kind regards,

Håkon

RE: nRF54L15 DK I2C and SPI Pins

Theja — Tue, 01 Apr 2025 05:25:02 GMT

Hi,

The above pin assignments are related to the nRF54L15DK. If we design a custom board with nRF54L15 SOC, can we use any pins, or are we required to use the same pins as assigned on the DK?

Regards,
Theja

RE: nRF54L15 DK I2C and SPI Pins

Edvin — Thu, 27 Mar 2025 23:27:17 GMT

Hello Theja,

I must admit that this information is a bit scattered. The Pin Assignments tables are quite helpful in this case:

https://docs.nordicsemi.com/bundle/ps_nrf54L15/page/chapters/pin.html#ariaid-title4

Search that page for SPIM00, and you will see your options. As for the I2C21, you can see from this table that the SCL pin needs to be a clock pin. The clock pins are marked with an "x" in the second column of the "pin assignments" table.

Note that TWI (two wire interface) = I2C. You didn't specify wheter you are using TWIM or TWIS, so I'll assume TWIM (but you can look up the same information for TWIS).

Here is a description of what pins you can use for TWIM21. Basically, any pins on P1, but if you need to use the higher speeds for TWI, then you can use the "dedicated pins on P2". I will look up tomorrow what pins these are. It is not clear to me, but perhaps they are the same as the SPIM21 pins. I will get back to you with this.

In the meantime, are there any particular needs with your SPIM/TWIM? What frequency/speed do you need? And are there any port or pins that you need to use?

Best regards,

Edvin