Access SCAN_REQ content.

[Luke Tucker]

We are currently researching which BLE chip vendor to use so this question is directed at Nordic personnel familiar with the S110 stack's capabilities.

In a situation where a peripheral runs on one nRF51822 device and the central runs on another nRF51822 device, the Peripheral sends an ADV_IND packet to the Central on an advertising channel. The Central is set up for active scanning and so sends back a SCAN_REQ packet containing the Peripheral's MAC and the Central's MAC as well as RSSI information. In return the peripheral now sends a SCAN_RSP packet.

Does the Nordic stack (S110) allow the the SCAN_REQ packet to be seen by the peripheral? I have a desire to extract that MAC address so that the central's MAC id becomes known to the advertiser.

If this cannot be done, is it possible to use the radio peripheral on the nRF51822 directly to achieve this? In short, send an advertisement on the 3 advertising channels and enter receive mode immediately after each transmission to check for a SCAN_REQ response from the central.

Regards

Luke Tucker

[David Edwin]

The S110 unfortunately does not send the Scan requests received over its interface. However you can get the allows you to directly run the radio and get the Scan requests and send the scan responses. An example to do so using the timeslot API in SoftDevice v7.0 is now available on the Nordic Github. This will send the SCAN REQ packet to the application with measured RSSI and also a link quality indicator based on the number of received packets that have passed/failed CRC checks.