Manually set resolvable address.

RE: Manually set resolvable address.

Hung Bui — Fri, 11 Aug 2017 11:53:13 GMT

Hi Jon,

How exactly did you set the sd_ble_gap_privacy_set() ? I just tested here with S132 v5.0.0 on SDK v14, it worked fine, I have new address everytime I called it and updated every minute. Here what I used:

privacy_param.privacy_mode=BLE_GAP_PRIVACY_MODE_DEVICE_PRIVACY;
privacy_param.private_addr_cycle_s=60;
privacy_param.private_addr_type=BLE_GAP_ADDR_TYPE_RANDOM_PRIVATE_RESOLVABLE;
privacy_param.p_device_irk= NULL;
err_code = sd_ble_gap_privacy_set(&privacy_param);

RE: Manually set resolvable address.

jon pry — Thu, 10 Aug 2017 15:17:32 GMT

I can't say why I need it except under NDA. The S132 V2 API provides the functionality I need, since it requires the user to generate the addresses, but I would prefer not to use the aging SDK.

As a work around, I could potentially deal with the randomly generated addresses, but I've run into an interesting bug. When I enable privacy through sd_ble_gap_privacy_set. The first address after power on it always the same. I am concerned that the sequence of addresses used may always be the same. I've also encountered bugs where the address rotation fails to happen even though a private resolvable address is clearly being advertised.

I guess that is my real problem with this new API. There is no control over how/when these "random" addresses are generated. There's really a lot of non ideal times to be rotating the address when operating as a central. For example when I see a device advertise I want to connect to, it would be best if the SD did not change my address for the next few seconds so that the connection attempt does not fail.

RE: Manually set resolvable address.

Hung Bui — Wed, 09 Aug 2017 12:07:46 GMT

I afraid this is restricted by the spec that the resolvable address shouldn't be set manually. This is due to the main purpose of the random resolvable address, to provide privacy.

Modifying RAM may not be a good idea, as you already experienced, in some functions, we do check the first bit.

Why do you need a static resolvable address ?