The devicetree does not correctly restrict peripheral pins.

[momososo]

I used the device tree to assist with schematic design, but after the PCBA was returned, I found that the peripheral functions could not be implemented normally.

It was confirmed that the problem was with the clock pin and that the nRF54L15 could not achieve a complete IO mapping. However, there were no errors or warnings when setting up the devicetree. As shown in the figure below, I2S MCK can select any pin.

Software from other manufacturers does not have this setting bug, which may lead to design errors.

Since nRF54 IO is not as flexible as nRF52 and 53 series, you should handle it specially or provide additional devicetree setting tools.

[Marte Myrvold]

Hi,

I have forwarded this internally to the team responsible for the VS Code extension. I will let you know when I have an update.

Best regards,
Marte

[momososo]

You should also update all the pin select register description in the datasheet.

There are many limitations so you shouldn't just copy and paste it to every register description.

I tried to get the Nordic Semiconductor AI to configure the IO, but I got the wrong pinout.

You should retrain and fine-tune it to suit the nRF54.

Thank you.

[Marte Myrvold]

Hi,

You can find information about which pins are restricted to clock pins and which can be used as clock signals in nRF54L15 datasheet - pin assignments. This is in chapter 10.1 in the PDF datasheet (page 859).

Best regards,
Marte

[momososo]

When designing the schematic, I noticed the "clock pins," but as far as I know, the MCU clock pin usually relates to the crystal oscillator or timer.

As you mentioned, the details are at the end of the PDF datasheet. I mainly followed the devicetree configuration and register references, as they seem more trustworthy. I hope the VS Code extension can be improved soon — the datasheet revisions can take more time.

I can’t be the only one who fell into this!

[Marte Myrvold]

Hi,

Thank you for the feedback.

The VS Code team is looking into this, but I cannot comment on the schedule since this needs to be prioritized against other tasks.

Best regards,
Marte