RE: Issue with HCI Communication on nRF5340

Yash48 — Thu, 27 Nov 2025 04:53:38 GMT

Hi Edvin, thanks for the help — I’ve solved the issue now.

RE: Issue with HCI Communication on nRF5340

Edvin — Tue, 25 Nov 2025 14:47:23 GMT

Hello,

In case you did, please avoid using AI to formulate your questions.

So you want to communicate directly with the network core, with a UART instance controlled by the network core, is that the case?

[quote user=""]Built the hci_uart example from the nRF SDK (default configuration).[/quote]

I assume you mean the nRF Connect SDK, not nRF5 SDK? What was your build command? What was the board target that you built for? And what NCS (nRF Connect SDK) version are you using?

Questions:

1: We don't have any sample doing this exactly.

2: No, not out of the box.

3: probably.

So you have the hci_uart sample, that you found in the nRF Connect SDK. You would have to build it for the nrf5340dk/nrf5340/cpunet, in order to target the network core. This then probably requires an nrf5340dk_nrf5340_cpunet.overlay file to provide the correct uart instance and uart pins.

Then you need to flash something on to the application core in order for it to start the network core. You can use the NCS\nrf\samples\nrf5340\empty_app_core for this. As long as this is flashed to the network core, it will boot up the app core, start the network core with whatever is programmed on it, and then go to sleep with the application core.

What do you intend to use the application core for, if I may ask?

Best regards,

Edvin