BLE4.2 and iPhone 7 throughput, PDU, packets per event and conn interval

[donnib]

Hi, I can see that Apple states that iPhone 7 supports LE Data Packet Length Extension forums.developer.apple.com/.../73168. Anyone know if the packets per event and the connection interval is different on the iPhone7 ? I am trying to calculate the potential througput i can get from this iPhone model.

/donnib

[run_ar]

Yes, it is different. And the behavior might change depending on the iOS version as well. This also depend on whether the peer support DLE or not.

iPhone 7 iOS 10.0.3, peer Without DLE:
ATT MTU size = 185 bytes.
Didn't test max number of packets but it depends on the connection interval as well. The connection event has to be ended before the next connection evnt.

iPhone 7 iOS 10 with DLE: PDU size: 251bytes, (2.12ms) ATT MTU size requested by iPhone:749 The maximum number of packets dependes on the connection interval and the capabilities of the peer.

I did a quick test with the experimental ble_app_att_mtu_throughput example in the SDK and I could send three packets with 244byte of actual data, ATT MTU size:247bytes pdu size 251byte, 30ms connection interval. But I don't think this is optimized for iOS as it is a nRF52 to 52 example.