Directed Advertising - How to make it work?!

RE: Directed Advertising - How to make it work?!

veletron — Tue, 30 Oct 2018 15:48:34 GMT

Cheers, I have disabled all directed advertising and am now using the whitelist method from the hid_keyboard example...

RE: Directed Advertising - How to make it work?!

Kenneth — Tue, 30 Oct 2018 12:29:50 GMT

For instance directed is not supported by iOS:
https://developer.apple.com/accessories/Accessory-Design-Guidelines.pdf (chapter 10.3)

You might also find other relevant information there.

RE: Directed Advertising - How to make it work?!

veletron — Tue, 30 Oct 2018 10:36:26 GMT

Oh.... As directed advertising appears to be a standard part of BLE 4.2 and all devices I am targeting are BLE 4.2 or better I assumed this would just work.

Guess I will have to forget directed advertising as a solution and return to fast advertising+whitelisting.

Unfortunately, the BLE is a tiny component in our project, but by far the most frustrating and time consuming component!

Nigel

RE: Directed Advertising - How to make it work?!

Kenneth — Tue, 30 Oct 2018 08:40:32 GMT

Hi,

It may be that the specific android phone you have don't support directed advertising. To ensure that directed advertising is supported the peripheral device should do a discovery of the central address resolution characteristic (CAR) of the phone, and if it is bonded and supported by the phone, then the peripheral can do directed advertisement. The implementation to check for CAR was included for the HID examples in SDKv15.2, you may try: \nRF5_SDK_15.2.0_9412b96\examples\ble_peripheral\ble_app_hids_keyboard for comparison.

Best regards,
Kenneth

RE: Directed Advertising - How to make it work?!

veletron — Mon, 29 Oct 2018 15:42:08 GMT

Still no joy, I changed the adv_directed_timeout from zero to 10000. App now runs through the available advertising methods. Still cannot re-connect while Directed advertising is being done, can connect after it switches to FAST, but that does not fit my requirements. I can only assume that nothing is being advertised during the 'directed' period- maybe there is another setting in the SDK that I need to enable?

I have checked that the MAC that gets stored away at initial bond time matches that of the device in question, and also that the same MAC is retrieved via ble_advertising_peer_addr_reply prior to directed advertising being started. Now at a total loss re how to make this work.

Edit: Just setup the sniffer - someone needs to look at the instructions for that, they are awful! Oh, and make it work with the 'nRF82840-Dongle' too (currently there is no way to get the firmware onto it).

Anyway, I am getting direct advertisment packets, despite nRFConnect (running on Android) complete refusal to re-connect to the peripheral using them.

10070 225.442 f6:d7:12:6c:99:d8 LE 1M LE LL 12 500 0 ADV_DIRECT_IND

10071 225.449 f6:d7:12:6c:99:d8 LE 1M LE LL 12 500 0 ADV_DIRECT_IND

Adv data thus, and the MAC of the central is in there 9C:E0:63:FC:FC:D6

0000 06 1f 00 02 86 35 06 0a 01 25 31 00 00 4f d7 02
0010 00 d6 be 89 8e 21 0c d8 99 6c 12 d7 f6 d6 fc fc
0020 63 e0 9c b6 ca e5

Wireshark screenshot below. Given that this does not even re-connect with nRFConnect (android), it looks like I shall have to give up! No hope of me getting it to work with my own app.

Nigel