Setting static random address more than once

[D0023]

Hello,

I am using bt_id_create() to set static random address.

bt_id_create() is called before bt_enable().

This works and sets the device address to a random address I specify.

But how can I change that address? For example - I have everything stopped (no connections, no advertisement), and I call bt_disable(). Then at some point later, I want to re-start BT but with different static random address. How can I do that?

I do not use settings, neither BT privacy. I just need to be able and use different static random address, when I enable BT.

Thank you,

D.

[Hung Bui]

Hi D0023, 

In stead of calling bt_id_create() you can call bt_id_reset() to change the address of the current identity. You would need to stop advertising before changing the address. 

Note that identity BT_ID_DEFAULT (which is 0) is not possible to reset. You can only reset identity >0. 

Please see the following code that I modified from the lbs example. The code will advertise with different addresses every 1 second: 

void main(void)
{
	int blink_status = 0;
	int err;
	struct bt_le_adv_param adv_param = {
		.id = BT_ID_DEFAULT,
		.sid = 0,
		.secondary_max_skip = 0,
		.options = (BT_LE_ADV_OPT_CONNECTABLE),
		.interval_min = 0x0020, /* 20 ms */
		.interval_max = 0x0020, /* 20 ms */
		.peer = NULL,
	};

	printk("Starting Bluetooth Peripheral LBS example\n");

	err = dk_leds_init();
	if (err) {
		printk("LEDs init failed (err %d)\n", err);
		return;
	}

	err = init_button();
	if (err) {
		printk("Button init failed (err %d)\n", err);
		return;
	}

	if (IS_ENABLED(CONFIG_BT_LBS_SECURITY_ENABLED)) {
		err = bt_conn_auth_cb_register(&conn_auth_callbacks);
		if (err) {
			printk("Failed to register authorization callbacks.\n");
			return;
		}

		err = bt_conn_auth_info_cb_register(&conn_auth_info_callbacks);
		if (err) {
			printk("Failed to register authorization info callbacks.\n");
			return;
		}
	}

	err = bt_enable(NULL);
	if (err) {
		printk("Bluetooth init failed (err %d)\n", err);
		return;
	}
	printk("Bluetooth initialized\n");

	if (IS_ENABLED(CONFIG_SETTINGS)) {
		settings_load();
	}
	err = bt_lbs_init(&lbs_callbacs);
	if (err) {
		printk("Failed to init LBS (err:%d)\n", err);
		return;
	}
	adv_param.id=1;
	err = bt_le_adv_start(&adv_param, ad, ARRAY_SIZE(ad),
			      sd, ARRAY_SIZE(sd));
	if (err) {
		printk("Advertising failed to start (err %d)\n", err);
		return;
	}

	printk("Advertising successfully started\n");

	for (;;) {
		dk_set_led(RUN_STATUS_LED, (++blink_status) % 2);
		k_sleep(K_MSEC(RUN_LED_BLINK_INTERVAL));
		bt_le_adv_stop();
		err = bt_id_reset(1,NULL, NULL);
		if (err < 0) {
			printk("Reset ID failed (err %d)\n", err);
		};
		err = bt_le_adv_start(&adv_param, ad, ARRAY_SIZE(ad),
			      sd, ARRAY_SIZE(sd));
		if (err) {
			printk("Advertising failed to start (err %d)\n", err);
		return;
		}
	}
}

Notice how I set the advertising identity to 1 by calling adv_param.id=1; . In the code I set address to NULL to generate random static address, but you can input your own address. 

Also you need to configure CONFIG_BT_ID_MAX=2

[MDL]

Hi,

I can not get this working on my nRF52840dk. I created a new application from the peripheral_lbs sample. I copied your code from above and added CONFIG_BT_ID_MAX = 2 to my .conf file.

bt_le_adv_start() returns -22 and when debugging I found that valid_adv_ext_param() in adv.c is returning false where param->id is equal to bt_dev.id_count:

if (param->id >= bt_dev.id_count ||

        !bt_addr_le_cmp(&bt_dev.id_addr[param->id], BT_ADDR_LE_ANY)) {

        return false;

    }

Tested with nRF Connect SDK v2.1.0 and v2.4.2.

Thanks.

[lionfish]

Hello,

I've got the same issue as MDL. I am using the nRF52832. I took the original version of peripheral_lbs and copied in the new version of main() as above. I also added CONFIG_BT_ID_MAX=2.

I noticed that it said "No ID address. App must call settings_load()" so I added a check to see if the settings_load method is working. I added a line to prj.conf CONFIG_SETTINGS=y.

Here's the output on the terminal:

Starting Bluetooth Peripheral LBS example
I: 6 Sectors of 4096 bytes
I: alloc wra: 0, fa8
I: data wra: 0, d4
I: SoftDevice Controller build revision:
I: 6d 90 41 2a 38 e8 ad 17 |m.A*8...
I: 29 a5 03 38 39 27 d7 85 |)..89'..
I: 1f 85 d8 e1             |....    
I: No ID address. App must call settings_load()
Bluetooth initialized
Loading settings...
Advertising failed to start (err -22)

adv_param has in it:

id:
1 '\001'
sid:
0 '\000'
secondary_max_skip:
0 '\000'
options:
1
interval_min:
32
interval_max:
32
peer:
0x0 <cbvprintf_package>

if that's useful?

ad has in it an array of two entries:

[0]
type:1 '\001'
data_len:1 '\001'data:0x2000075c <__compound_literal.1> "\006\002#Ѽ\352_x#\025\336\357\022\022%\025"
[1]
type:9 '\t'
data_len:10 '\n'
data:0x27ba7 "Nordic_LBS"

I realise I've the same problem

param->id >= bt_dev.id_count

it makes sense this should cause an error (as it's zero-indexed), but it's not clear how I make the 'id_count' bigger?

Should I be calling bt_id_create?

I wonder if it has anything to do with this issue?

[Vidar Berg]

continued in this thread:  bt_le_adv_start() returns -22, with adv_param.id=1