More information about "SKIP" and "TIMEOUT" parameters of BLE 5 advertising

Question

Hi 
 
 I am working on an application that uses extended periodic advertising feature of BLE 5. In this sample (periodic sync): 
 https://github.com/nrfconnect/sdk-zephyr/blob/main/samples/bluetooth/periodic_sync/src/main.c 
 
 There are two parameters, "skip" and "timeout" which are set before making the sync at receiver side. 
 sync_create_param.skip = 0;
sync_create_param.timeout = 0xa;
err = bt_le_per_adv_sync_create(&sync_create_param, &sync); 
 
 How these two parameters affect on making/termination of the sync? And what is the difference between these two? 
 As I can find in the documentation (of Zephyr), it describes these parameters as follow: 
 skip : Maximum number of periodic advertising events that can be skipped after a successful receive. 
 timeout : Synchronization timeout for the periodic advertising sync. 
 
 It is not clear how the sync termination is determined, after "skipping maximum events (skip parameter)" or after "not receiving data for a while (timeout parameter)". How is it determined?

tesc · Accepted Answer

Hi, 
 The synchronization is considered to be lost if the timeout time passes from the last successfully received periodic advertising packet. 
 The skip parameter, on the other hand, allows the device to not listen for advertising events skip number of times, before it must do an attempt at listening again. 
 The value of skip will be ignored (the device will listen for the advertising event anyway) if the timeout is about to run out. 
 According to the Bluetooth Core specification, the valid range for skip is 0x0000 to 0x01F3 . I did not find that range documented for the API call in nRF Connect SDK / Zephyr, and have filed an internal issue report. 
 Regards, Terje

More information about "SKIP" and "TIMEOUT" parameters of BLE 5 advertising

Top Replies