nRF53: net core image with BLE controller and Radio Test functionality

[Benno Trutmann]

Hi.

I would like to build a FW image for the nRF5340 net core which includes the two mode BLE controller part and Radio Test (like in the Radio Test sample). These two modes should only run mutual exclusive and there should be a possibility to switch between the modes via trigger from the application running on the app core. Also the configuration of the Radio Test should be possible from the application.

1) Is it possible to build such an net core image? And if yes, how would I do it with the nRF Connect SDK?

2) What is the easiest way to control the Radio Test from the application running on the app core?

Thanks,

Benno

[Susheel Nuguru]

1) Is it possible to build such an net core image? And if yes, how would I do it with the nRF Connect SDK?

it is possible but seems like a huge work to integrate these two builds together as there might be conflicts in the resources used in each build. Also ability to use radio test in side of BLE controller will need you to use MPSL (already part of BLE controller) to synchronize timeslots that the radio_test uses to get mutually exclusive access to all peripherals during that timeslot.

2) What is the easiest way to control the Radio Test from the application running on the app core?

rpmsg might be a interesting candidate to look into for sending messages from the app core.

[Benno Trutmann]

Is MPSL really needed for my scenario?

In the end the device should work in one of two separate modes:

1. Normal mode, where BLE is used, but no radio test functionality is needed, and

2. Radio Test mode, where constant TX carrier and TX sweep is needed, but not BLE functionality is used.

These two mode are separate, but there should be a way to switch from one to the other.

[Susheel Nuguru]

MPSL is only needed if you want both features to be active and operating concurrently. If the use case is to use BLE only and disable BLE before using radio test mode, then you do not need MPSL. In that sense, it is bit easier to integrate the two features as they are then mutually exclusive for chip resources.

[Benno Trutmann]

What is the correct way to completely disable BLE?

I found no counterpart to bt_enable().

[Susheel Nuguru]

Seems like there is no direct bt_disable function .
Looking at the sample code written here, and looking at the nordic implementation of zephyr\soc\arm\nordic_nrf\nrf53\power.c, the only way to disable bt is now to turn off your platform.

In your case, this might be also helpful, if you write to flash some data before shutting down. On reboot, based on the data written, your application can decide if it initializes bt or the radio test.