Detecting scan response request at peripheral

RE: Detecting scan response request at peripheral

Kenneth — Tue, 17 Jun 2025 13:45:37 GMT

Hi,

When you start to advertise you can choose this by e.g. when calling bt_le_adv_start(), use the BT_LE_ADV_OPT_NOTIFY_SCAN_REQ option. But then you also need to add a callback .scan_req_received = your_funtion in adv_callbacks().

Kenneth

RE: Detecting scan response request at peripheral

Mike Austin (LPI) — Mon, 16 Jun 2025 19:24:37 GMT

Hi Kenneth,

I am looking into the energy budget of reverting to System On with idle compared to going into System Off, as I can see there is about a 500msec start delay exiting System Off. The System Off is a bit of a legacy design feature on this project.

In terms of getting the peripheral to detect and report a scan request in my firmware, is there a CONFIG setting I need to enable? And then some callback that I need to add to process the detection of a scan request?

I had a search on the DevZone but could t find anything that would answer those questions.

Thanks,

Mike

RE: Detecting scan response request at peripheral

Kenneth — Mon, 16 Jun 2025 11:46:39 GMT

Hi,

Normally it's less power consumption to use normal system ON idle to periodically run the application with e.g. advertisement than using an approach with system OFF if you do any activity more often than a few minutes. The reason for this is that the time to re-init the device comes with a cost compared to just draw 3-4uA continuously.

But to answer your question; The peripheral advertising should be able to detect both a SCAN request response and CONNECT request packet while advertising, the application can use this to decide whether it should go to system OFF or not.

Kenneth