Application and code example for using two cores in nRF5340

RE: Application and code example for using two cores in nRF5340

Maria Gilje — Wed, 06 Dec 2023 12:17:34 GMT

Do you see any reference to rpmsg in the build log?

If you want insight on the memory usage per thread, you can use Zephyr's Thread Analyzer.

RE: Application and code example for using two cores in nRF5340

lcj — Wed, 06 Dec 2023 12:00:46 GMT

I built an app using the nRF connect for VSC addin and based it on the cpuapp board. I have built ble connectivity into it but I don't think I did it any differently than if I were on a single core board. It's working but I'm not really sure why and if there are memory constraints when I am doing work on a ble thread.

RE: Application and code example for using two cores in nRF5340

Maria Gilje — Tue, 28 Nov 2023 13:25:59 GMT

Hi again,

[quote user=""]Does the HCI RPMsg receive the bluetooth communication and pass it off to peripheral_lbs? How does it work?[/quote]

In this documentation you can read about the Bluetooth Stack Architecture. It contains an overview of the dual-chip configuration which is the configuration normally used with the nRF5340 (controller on the network core and host on the application core).

HCI RPMsg is based on OpenAMP which has its documentation and source code here.

[quote user=""]Is there an example of how to develop an application using the nRF5340 demonstrating how to use the two cores when developing an application?[/quote]

I recommend that you use the product specification and the .dtsi for the nRF5340 (nrf5340_cpuapp* and nrf5340_cpunet*) to get familiar with which peripherals are available for each core. For example: the application core does not have access to the radio peripheral which is why the dual-chip configuration is used for the Bluetooth stack.

Best regards,

Maria

RE: Application and code example for using two cores in nRF5340

Maria Gilje — Mon, 27 Nov 2023 14:27:49 GMT

Hello,

I have picked up this case and will answer some of it today. Tomorrow I will elaborate and address the rest.

[quote user=""]What I do not understand is how the code needs to change in the peripheral_lbs and HCI RPMsg?[/quote]

The general answer: When CONFIG_BT=y in your project configuration (prj.conf) and the build target is the nRF5340 application core, HCI RPMsg will automatically be built for the network core.

The specific answer: Peripheral LBS has CONFIG_BT=y in prj.conf which means the HCI RPMsg sample will automatically be built for the nRF5340 network core when Peripheral LBS is built for the nRF5340 application core. So there is no need to change anything in either sample.

Best regards,

Maria