advertising time interval

[nordicbeginner]

hello there in my code, APP_ADV_INTERVAL 64 APP_ADV_TIMEOUT_IN_SECONDS 5 using nrfsniffer i am getting 57 packets in 1 second. i can't understand it. because APP_ADV_INTERVAL 64. so it should be 40 ms.. so in 1 second i should get 25 packets.

can anyone tell me, why i am getting 57 packets??

[Jeong Hyun Seok]

Let me show you general ADV sequence

1. send ADV via 37 channel (and small interval)
2. send ADV via 38 channel (and small interval)
3. send ADV via 39 channel
4. then, interval 40 ms
5. repeat 1)2)3)4

so they will send under 75 packets per second.

in my device, send ADV takes about 272 us and small interval of 665 us

so 1)2)3) spends around 2ms. total 1)2)3)4 = 42 ms