MAC address randomly set to 00:00:00:00:00:00

Question

Hello, 
 I do migration from SDK11 to SDK12 (S132-SD-v2.0.1 to S132-SD-v3.1.0) and my device (nRF52-DK) randomly got a MAC of 00:00:00:00:00:00. 
 Helped by the migration document, I configure random private non resolvable MAC address with: 
 #define BLE_GAP_PRIVATE_ADDR_CYCLE_INTERVAL_S (15 * 60)
sd_ble_gap_privacy_set(&(ble_gap_privacy_params_t) { 
	.privacy_mode = BLE_GAP_PRIVACY_MODE_DEVICE_PRIVACY,
	.private_addr_type = BLE_GAP_ADDR_TYPE_RANDOM_PRIVATE_NON_RESOLVABLE,
	.private_addr_cycle_s = BLE_GAP_PRIVATE_ADDR_CYCLE_INTERVAL_S,
	.p_device_irk = NULL
});
 
 This erroneous MAC address prevent device detection from Apple iphone/ipod. 
 Moreover, the MAC address seems to change after (during?) each connection !? 
 Do you see my mistake? Can someone help me? 
 Thanks!

Petter Myhre · Accepted Answer

Your code is correct, I just tested it here, and I get the same behavior. 
 It should not be 0, and is a bug. I will update this answer when it is fixed. 
 With the non-resolvable address type the address will change every number of seconds you set private_addr_cycle_s to, so this is expected. 
 And after the first private_addr_cycle_s seconds a proper random non-resolvable address is used, instead of 0. Then iOS should be able to connect. 
 Now you are setting private_addr_cycle_s to 15 * 60 s = 15 min. If 15 min is too much, the workaround is to decrease it. 
 The device address is not used while you are in a connection, so you don't have to worry about it changing then. 
 Edit: It seems like a reset will also remove the issue. 
 Edit2: Or put a delay after ble_stack_init(), like nrf_delay_ms(2).

MAC address randomly set to 00:00:00:00:00:00

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