BLE_GAP_ADV_TYPE_ADV_IND used with whitelist

RE: BLE_GAP_ADV_TYPE_ADV_IND used with whitelist

Valer_I — Mon, 14 Sep 2015 14:46:03 GMT

The low duty cycle needed when device avaiting avalability of centrall to connect. If nrf based device is wearable it could be used to detect it in the range of central and connect it. So please make 0x04 type for us.

RE: BLE_GAP_ADV_TYPE_ADV_IND used with whitelist

Ulrich Myhre — Mon, 28 Jul 2014 04:08:26 GMT

This is correct. Directed advertising is advertising to a specific scanner/observer in hope of quickly getting a connection going. It is defined per the spec to have specific timeouts and intervals, so these should be ignored. You do need to set the peer address though, so directed advertising is mostly used for bonded devices that you have recently been in contact with (e.g. after disconnecting and sleeping for a few minutes). If directed advertising times out, a common pattern is to fall back to (whitelisted) indirect advertising to save power.

It is also correct that the current softdevices do not support the low duty circle variant, but I bet Nordic would be interested in knowing why this is a requirement for you :)

RE: BLE_GAP_ADV_TYPE_ADV_IND used with whitelist

Erik Sanchez — Fri, 25 Jul 2014 14:44:02 GMT

After re-reading the the Bluetooth Specification Vol2 section 7.8.5 and also studying the ble_gap.h header file I think I understand.

When using an advertising type of BLE_GAP_ADV_TYPE_ADV_DIRECT_IND you need to set

interval = 0;
timeout = 0;

You then set your p_peer_addr to your know peer.

I also believe that the whitelist will be ignored since we do not need to filter on a directed advertisement.

As a side note, BLE_GAP_ADV_TYPE_ADV_DIRECT_IND (0x01) is a high duty cycle directed advertising type so the interval and timeout are dictated by the specification.

I'm interested in low duty cycle directed advertising (0x04) but this does not seem to be supported by the API since there is no 0x04 type in the ble_gap.h header file.