RE: nRF54L15 which GRTC interrupt to use

tmav — Fri, 21 Nov 2025 08:06:55 GMT

Many thanks for your help.

RE: nRF54L15 which GRTC interrupt to use

Einar Thorsrud — Thu, 20 Nov 2025 14:03:24 GMT

Hi,

I do not believe there is a list of reserved GRTC channels, but what you are describing is a common use case for which I recommend you use the Bare Metal Timer library, which is intended for this purpose (when using the periodic timer). That is demonstrated in the Timer sample, and you can also see an example of it being used in the CGMS sample.

Edit: In case it is useful for other uses, GRTC channels 7 to 11 and interrupt GRTC_3_IRQn are reserved for the SoftDevice (The SoftDevice from the bare metal SDK has the same reserved hardware resources as the MPSL and SoftDevice Controller, as you can see in Hardware peripherals from the S115 SoftDevice Specification.