Direction finding connectionless sample doesn't work on my nrf5340dk

[filipang]

Hello!

I will start by saying that I am new to embedded software development, and new to nrf boards in general.

After successfully running the direction finding connectionless (rx and tx) samples on my nrf52833dk, I want to run it on my nrf5340dk. I ran into a difficult issue when trying to flash the bluetooth controller on the network core. I think I followed the exact steps that are specified in the README of https://github.com/zephyrproject-rtos/zephyr/tree/main/samples/bluetooth/direction_finding_connectionless_rx#id5. 

I copied the .overlay file with the pin configuration into the hci-rpmsg sample and modified it accordingly, and then I copied the .conf file from the direction_finding_connectionless boards folder and changed its name such that it configures the cpunet (like the README says). When I try to flash the code for the cpunet, it seems that there is not enough RAM on the network core. (It says that I overflowed by around 20 kilobytes)

I then tried flashing the hci-rpmsg sample unmodified, and saw that by itself it was allocating ~60% of the 64kB of RAM. (Which was already a bit surprising to me)

It seems that when pasting and modifying the .conf file from the direction_finding_connectionless_rx (same happens with tx, except it overflows with about 12kB) the RAM overflows by quite a lot (So I can't just cut some of the 8kB of heap memory because it wouldn t be enough), which is weird and it leads me to believe I am doing something very wrong. Perhaps I don't need all the settings that are in there? I did try to play around with the settings in the hope it would work but I am now completely stuck.

Any help or tips would be greatly appreciated!

[filipang]

Hello,

Should the child_image/hci_rpmsg.conf file appear by itself? Because for me it does not when I build. (And there is no child_image folder either)

I removed the two files I added manually (so now the hci_rpmsg sample is unmodified), and building the direction_finding_locator sample works (This happened before so nothing new here, I assumed that I needed those configurations to get it to work, which I added because it is what the readme says), but when I flash it on the nrf5340dk I get the following error:

Waiting for periodic advertising...*** Booting Zephyr OS build v3.1.99-ncs1-1  ***
Starting Connectionless Locator Demo
Bluetooth initialization...success
Scan callbacks register...success.
Periodic Advertising callbacks register...success.
Start scanning...failed (err -5)
Waiting for periodic advertising...

Whereas when I run it on my nrf52833dk (Exact same setup and sample except I use the command for the nrf52) everything works exactly as expected.

Is the following section from the sample README not up to date? Because these are the exact steps I followed and it does not work for me due to that memory overflow issue.

To run the application on nRF5340DK, a Bluetooth controller application must     
also run on the network core. The :ref:`bluetooth-hci-rpmsg-sample` sample       
application may be used. To build this sample with direction finding support     
enabled:                                                                         
                                                                                 
* Copy                                                                           
  :zephyr_file:`samples/bluetooth/direction_finding_connectionless_rx/boards/nrf52833dk_nrf52833.overlay`
  to a new file,                                                                 
  :file:`samples/bluetooth/hci_rpmsg/boards/nrf5340dk_nrf5340_cpunet.overlay`.   
* Make sure the same GPIO pins are assigned to Direction Finding Extension in file
  :zephyr_file:`samples/bluetooth/direction_finding_connectionless_rx/boards/nrf5340dk_nrf5340_cpuapp.overlay`.
  as those in the created file :file:`samples/bluetooth/hci_rpmsg/boards/nrf5340dk_nrf5340_cpunet.overlay`.
* Copy                                                                           
  :zephyr_file:`samples/bluetooth/direction_finding_connectionless_rx/boards/nrf52833dk_nrf52833.conf`
  to a new file,                                                                 
  :file:`samples/bluetooth/hci_rpmsg/boards/nrf5340dk_nrf5340_cpunet.conf`. Add  
  the line ``CONFIG_BT_EXT_ADV=y`` to enable extended size of                    
  :kconfig:option:`CONFIG_BT_BUF_CMD_TX_SIZE` to support the LE Set Extended Advertising
  Data command.                                                        

Perhaps you could explain what exactly is wrong with the steps I took, because I don't seem to be making any progress with this problem by myself. From what I understood before you said I don't need the .conf file, which I worm but it still doesn't work. like it does on the nrf52833dk. Maybe it has something to do with the child_image folder that I don't have.

Best regards,

Filip.

[dejans]

Hi Filip,

It might be that you are using Zephyr sample instead of nrf sample. When creating freestanding application in VS Code choose application template to be nrf\samples\direction_finding_connectionless_rx. I have tested using nrf sample. Folder child_image is automatically created in your application directory and includes hci_rpmsg.conf file.

Best regards,
Dejan

[filipang]

Hello,

Thank you so much for all your responses, it seems that was indeed the issue, should have been using nrf sample instead of zephyr!

Best regards,

Filip.