Non-scannable advertising

[Jason]

I advertise as 

• BLE_GAP_ADV_FLAGS_LE_ONLY_GENERAL_DISC_MODE
• BLE_GAP_ADV_TYPE_NONCONNECTABLE_NONSCANNABLE_UNDIRECTED

This posts suggests I may have not really disabled the scan response.

https://devzone.nordicsemi.com/f/nordic-q-a/56616/how-to-disable-scan-response

I set  adv_params.scan_req_notification = 1; and I do not see a scan request logged when my phone scans.

The final reply in the following thread says "Note that some phones might not support a peripheral that doesn't send a scan response, even if it is just an empty reply."

https://devzone.nordicsemi.com/f/nordic-q-a/20796/disable-scan-response

I have no problem reading the advertisements on my android phone (Samsung M31). Can anyone clarify which phones I might have a problem with? 

Does Nordic know of any testing facilities that I could send my product for compatibility testing with the most popular handsets?

Thanks for your help,

-Jason

[Simonr]

Hi Jason

You can check if there is an empty scan response by using a sniffer device (I.E. the nRF sniffer) to sniff all data that is transmitted on the BLE band. It does indeed seem like you have not disabled the scan response completely, as that is only possible if you use the whitelist advertisement feature.

I'm sorry, but we do not have a list of which phones this would be. I still think the devices should be able to scan for these devices, but may have issues if you want to connect to the peripheral, but it seems like you're not going to connect to these devices, correct?

Best regards,

Simon

[Jason]

Correct, no connections from the non-scannable advertising. Just a few bytes of sensor data etc.

I allow connections briefly if the device is turned on it's head. I change the advertising and I have no problems. The scan response then contains the service UUID.