Sniffing Extended Advertising with hci_ipc on nRF5340

[emaglio]

Hi all,

I’m working on an nRF5340 project where the network core runs a hci_ipc firmware to forward HCI RAW packets to the application core, which then parses vendor-specific information from Bluetooth advertising data. Legacy advertising works fine, and I receive and process those packets as expected. However, I have run into some snags attempting to sniff Bluetooth 5 extended advertising packets.

My application core already calls bt_le_scan_start() with passive scanning and registers a bt_le_scan_cb callback to capture all advertising data. My netcore prj.conf for hci_ipc currently contains:

CONFIG_IPC_SERVICE=y
CONFIG_MBOX=y
CONFIG_HEAP_MEM_POOL_SIZE=4096
CONFIG_MAIN_STACK_SIZE=512
CONFIG_SYSTEM_WORKQUEUE_STACK_SIZE=512
CONFIG_BT=y
CONFIG_BT_HCI_RAW=y
CONFIG_BT_MAX_CONN=16
CONFIG_BT_EXT_ADV=y

However, I noticed that in the build logs:

“CONFIG_BT_EXT_ADV was assigned the value y, but got the value n. Missing dependencies:

((!HAS_BT_CTLR || BT_CTLR_ADV_EXT_SUPPORT) && BT_RPC_STACK) || ((!HAS_BT_CTLR || BT_CTLR_ADV_EXT_SUPPORT) && BT_HCI && BT)”

I imagine what I’m trying to do is possible and I’m just not configuring properly. I’ve done some searching for examples but haven’t come across any that are a direct match for this use case. What should I be looking at in order to successfully capture BT5 extended advertising packets?

Thanks in advance!

[Einar Thorsrud]

Hi,

I have not teted this exact use case (or seen other reference to it either), but  suspect you may also need CONFIG_BT_CTLR_ADV_EXT=y. And potentially other configs as well, like CONFIG_BT_CTLR_PHY_CODED=y if you want to scan on coded PHY for instance. Maybe you can use he central HR coded sample as a reference (i does scan for extended advertising and supports the nRF5340).

[emaglio]

Thanks! I was able get everything up and running by incorporating some configuration and scanning option changes from the central HR coded sample.