SDK15.2.0 Blinky and Multilink packet loss

[yellan]

I use Multilink and Blinky Demo with PCA10056 and PCA 10040 Board,when the two board close to each other  there is no packet loss,but when i dispath each other with 50cm,there will be lot of packets loss, Then i go to the underground garage and fond there is no 2.4G signal, some packets loss too.

Is there some error with the demo?

[Edvin]

Hello,

Can you describe what you mean with packet loss? Do the devices disconnect, or does it take longer for the LEDs to turn on/off? It is not expected to see a worse performance when you extend the range to 50+cm. 

Can you describe how your DKs behave?

BR,

Edvin

[yellan]

First,we set the update intervals to 10ms,then i set sd_ble_gap_scan_stop() after the central connected to the peripheral;

Send,i push data when the BLE_GATTS_EVT_HVN_TX_COMPLETE has occured;

Third i use frontline to get the packets,i find that there is something wrong with the demo,some packets loss,the frontline file just like thisfirst.cfa

[Edvin]

Is this sniffer log from the test that you did? Or does it look "something like this"?

You can't guarantee to not loose packets. But the SoftDevice will retransmit all packets that are not ACKed. This is part of the BLE specification.

So what do you mean by packet loss? That the packets are sent on the next connection interval? Or do you mean that they are not sent at all?

[yellan]

The cfa file is picked by BLE test device FrontLine,it's done when the demo was tested.

The packets not send on the next connection interval.

[Edvin]

I don't see anything wrong from your sniffer log, but I am not very familiar with ComProbe. Is it possible to do a sniffer trace using the nRF Sniffer? Any packet that is sent with the softdevice that is not acked will be retransmitted by the softdevice, so I don't think this is what you are seeing. Can you describe the behavior that you expect, and the behavior that you are seeing?

BR,

Edvin