BLE Scan Packet Receive Latency When Done Along Side Mesh.

[Sivaguru Ravi]

Hi,

Scenario:  Scanning  non mesh BLE packet with different stacks.

H/W Device -  nRF52DK

Observation:

Case 1. Non Mesh BLE Stack (Soft device):: Here able to receive scan packets in less than 1 sec interval.

Case 2. Mesh stack device                          : Here the scan packets are received around 10 to 15 secs of interval..

Is this expected behavior in mesh stack? Is there any way to decreases the latency between the reception of scan packets when done along with mesh?

Note: There is no difference in the advertisement frequency/packet in both the cases.

[Anne van Rossum]

Where can the code be adjusted to also receive scan responses? At https://github.com/NordicSemiconductor/nRF5-SDK-for-Mesh there is a scanner_packet_process_cb in nrf_mesh.c. Are scan responses received but filtered. Or what's exactly the implementation?

[Sivaguru Ravi]

I have combined ble scan example from sdk 11 and the mesh sdk light bulb example. The thing is since both mesh and the BLe soft device scan essentially uses the same scan apis internally we need not go making changes to mesh stack.

[Anne van Rossum]

This also means scan responses?

[Sivaguru Ravi]

yes

[Anne van Rossum]

So, how does this match with the response by tesc who explained that the Link Layer of the Bluetooth mesh stack only supports passive scanning?

1. Either you have implemented an alternating approach between BLE scanning and the mesh stack operation like @tesc says.

2. Or perhaps another device is doing active scanning and this device picks up the scan responses while it does not itself send out scan requests?