Reconnecting in central mode

[GT]

I am developing an application on nRF52 wich simultaneously acts as a central and peripheral and I am using the Peer Manager to manage bonding. The central needs to stay connected with a few already bonded peripherals which can occasionally get out or reach and disconnect. Therefore, if not all peripherals are connected, a scanning will be constantly running. The application parses all received advertising reports and first filter them out based on the Manufacturing specific data and then on the Flags. And here it comes the question - how do I filter out the advertising reports further and distinguish the ones coming from devices which have already got a valid bond with this particular central? Does the Peer Manager or the ID Manager provide this functionality or the application needs to keep track on that based on for instance peer addresses?

[Hung Bui]

Hi GT,

Yes, you can manually check the address of the advertiser when you receive advertising and compare to the list of device connected/paired.

But the esier way is to let the radio filter out advertising packets for you automatically. You can do that by providing a whitelist to the softdevice when doing scanning. The list of paired device can be acquired by calling pm_whitelist_get(). You will have address and IRK of the devices paired, and you can do selective scanning based on this list.

Please have a look at the scan_start() function in main.c in ble_app_hrs_c project in our SDK.

[GT]

Could you be more specific on this: "Note that if you set the bit in addr_id_peer in p_peer_addr, the address have to be added to the device identity list."

The code that I am working with looks exactly like the example given in the ble_app_hrs_c project. The application that I am developing requires maintaining a connection with multiple peripherals, therefore I was trying to avoid keeping track on peripheral's addresses in the application code.

I am not sure if this brings any value to the discussion, but if I disable the whitelist right before I request a connection, the connection goes fine. Like this:

m_scan_params.use_whitelist = 0;
err_code = sd_ble_gap_connect(&addr, &m_scan_params, &m_connection_param);

The values of the parameter passed to the sd_ble_gap_connect() are as expected when checked with a debugger.