nRF5340 Radio Notification callback alternative

RE: nRF5340 Radio Notification callback alternative

bihlori — Thu, 02 Oct 2025 13:00:44 GMT

Thank you!

RE: nRF5340 Radio Notification callback alternative

Einar Thorsrud — Thu, 02 Oct 2025 12:43:41 GMT

Hi,

I am thinking about using the approach described here in the product specification. Alternatively, you can use the Zephyr icmsg IPC service that use this together with shared RAM under the hood (similarily to what is suggested here, though for a different usecase).

RE: nRF5340 Radio Notification callback alternative

bihlori — Thu, 02 Oct 2025 12:04:51 GMT

Could you elaborate on the IPC -> DPPI communication? How can I trigger a DPPI event from IPC?

RE: nRF5340 Radio Notification callback alternative

Einar Thorsrud — Wed, 01 Oct 2025 12:37:41 GMT

I see. That will be difficult. As you write, radio notication requiers the host and controller to run on the same core and I am having problems seeing any other way to implement this.

If you have not come far in the development, perhaps it could be worth considering an nRF54L device instead? For isntance the nRF54L15 has ample memory, but does not have the complexities of a dual core device like nRF5340 and will let you use radio notifications.

RE: nRF5340 Radio Notification callback alternative

bihlori — Wed, 01 Oct 2025 12:24:48 GMT

I update a GATT Characteristic with the given radio delay each connection interval that needs the precision by the radio notification callback. If I use a radio event (txready) I will be late with the updating, therefore there will be a connection interval delay.

RE: nRF5340 Radio Notification callback alternative

Einar Thorsrud — Wed, 01 Oct 2025 12:15:22 GMT

What do you need radio notifications for more precisely? Could it be enugh to hook some chosen radio events up from the net core via DPPI -> IPC (from net to app) -> DPPI -> EGU to get interrupts on the app core on relevant radio events?

RE: nRF5340 Radio Notification callback alternative

bihlori — Wed, 01 Oct 2025 12:11:26 GMT

I have seen these, but because I don’t have the Bluetooth host built on the network core, I get build errors when calling the radio notification register function.

bt_conn_unref, bt_conn_get_info and other functions are undefined.

Maybe I am just misunderstanding the build process and I am not including something in the network core build? I am using a modified version of the hci_ipc sample because I am handling custom IPC commands as well.

RE: nRF5340 Radio Notification callback alternative

Einar Thorsrud — Wed, 01 Oct 2025 11:56:48 GMT

Hi,

There is no ready made solution for radio notifications on the app core on nRF5340. There are potential ways to achieve it or somethign similar though, for instance ad decribed here or here.