Configuring and building a nRF5340 project for Dual core

[Omegaki113r]

I am working on a project that uses BLE (as peripheral) and some other sensors are connected to the MCU too.

My goal is to run BLE on network core and Sensor data retrieval on App core.

I can't find any examples in your documentation. Can you share some links that shows me how to generate/configure a project that enable me to develop a firmware that can run on both cores and enable me to communicate between 2 cores

[Omegaki113r]

Hi.

i was looking in the wrong Directory. i was searching on Zephyr directory.
I needed to look at the "nrf" directory and i found the multicore_hello_world project. That was the exact project i was looking for.


So for anyone searching for example code for getting started with dual core. Navigate to following:

nRF SDK location => nrf => samples => multicore => hello world   

FYI => this is for v2.4.1   (Just in case this location is changed in the future versions)

[Håkon Alseth]

Hi,

 

Please note that when building any bluetooth sample for nrf5340dk_nrf5340_cpuapp, it will automatically add the network core image "hci_rpmsg" for bluetooth connectivity:

https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/device_guides/working_with_nrf/nrf53/nrf5340.html#multi-image-builds

 

Kind regards,

Håkon

[Omegaki113r]

So does that mean let's say i build and flash "peripheral_hr_coded" example. it will automatically build an image for "network core" and flash it to the "network core"

So eventhough i select "cpuapp" as the board. the BLE code will run on Network code??

[Øivind]

Hi,

Yes, the SDK will automatically build the hci_rpmsg sample for the cpunet board and include it in your build as a child image of the cpuapp image. This sample is found at zephyr/samples/bluetooth/hci_rpmsg.

If you would like to make any prj.conf or devicetree changes to the cpunet image, you can add a folder to your main project and call it "child_image". In this folder you can for example add a file named hci_rpmsg.conf which should contain any config changes and a file named hci_rpmsg.overlay for any devicetree changes. These files will be merged with the default hci_rpmsg sample.
https://developer.nordicsemi.com/nRF_Connect_SDK/doc/latest/nrf/config_and_build/multi_image.html#permanent-configuration-changes-to-child-images

Since the bluetooth controller is on the network core, if you would like to change the controller configs from the default, some controller specific configs need to be passed to the cpunet image in this way.

Please let me know if there is anything that is not clear.

[SvenDufva]

I've follow-up question on this. If SDK will automatically build the hci_rpmsg sample, how can I run my own custom application in parallel? Right now, my net core application runs nicely (basic loop spitting log messages) but after I enable BT (recompile and flash) the things stop working.

[Øivind]

To disable the automatic inclusion of the hci_rpmsg image, add CONFIG_NCS_INCLUDE_RPMSG_CHILD_IMAGE=n to your prj.conf file.