Understanding periodic advertising using periodic_adv and periodic_sync

Question

Hello, I am a beginner with the Nordic development kits. I have purchased two nRF52833 development kits and I would like to perform Bluetooth Direction Finding with these kits. Before that, I would first like to implement periodic advertising of BLE packets to understand what happens before I jump into direction finding. 
 I have seen that periodic_adv and periodic_sync are two examples that I can run to understand their working. The periodic_adv sends periodic advertising data every 10 seconds as given in the sample. But I am unable to receive the packets in the periodic_sync. I have not made any changes to the sample code. I would like to know what I am missing out and maybe some guidance on how I can send different data in place of the mfg_data[]. 
 I have attached the serial monitor log for both the periodic_adv and periodic_sync. 
 Periodic_adv:

Periodic_sync: 
 Here, it does not print the program code but some other data and says few messages dropped.

Menon · Accepted Answer

Hello, 
 The timeout parameter in the sync creation process might be the reason for the periodic sync getting lost. See sync_create_param.timeout = 0xaa inside the main file of the sample; this sets the timeout parameters for the advertising synchronisation process. This specifies the maximum time that can pass without successfully receiving a periodic advertising packet before the synchronisation is considered lost. So from the sample, synchronisation will be considered lost if no packets are received in 1.7 sec/1700 ms (0xaa = 170 * 10 ms). See the below threads, which discuss more on this: 
 https://devzone.nordicsemi.com/f/nordic-q-a/84232/more-information-about-skip-and-timeout-parameters-of-ble-5-advertising 
 https://devzone.nordicsemi.com/f/nordic-q-a/103167/bt_le_per_adv_sync_create-term-event-timing . 
 
 Kind Regards, 
 Abhijith

Understanding periodic advertising using periodic_adv and periodic_sync

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