BLE not connecting after disconnect

RE: BLE not connecting after disconnect

Zugislav — Wed, 05 Mar 2025 13:34:13 GMT

Wow i missed that somehow and thank you for noticing it.

i now what in main there is a endless loop since i cut out most of my code so only BLE related code is being sent in zip file.

Thank you again for you help!

RE: BLE not connecting after disconnect

Vidar Berg — Wed, 05 Mar 2025 13:06:21 GMT

Thanks for sharing the code. The issue was that you were increasing the reference count for the connection object with '2' in your connected callback, but you only released one of them in your disconnected callback. The advertiser does not resume until the reference count is 0. Solution is to only call bt_conn_ref() once.

You also had an endless loop in main() in the code you provided me. This will block other threads such as the logger thread.

RE: BLE not connecting after disconnect

Zugislav — Wed, 05 Mar 2025 09:55:57 GMT

ill make some changes and upload it to a private ticket.

RE: BLE not connecting after disconnect

Vidar Berg — Wed, 05 Mar 2025 09:45:43 GMT

Can you upload a minimal version of your project here or in a private ticket so I can reproduce the problem and debug the problem on my end?

RE: BLE not connecting after disconnect

Zugislav — Wed, 05 Mar 2025 09:19:03 GMT

i still doesnt work after i removed it.

i accidentaly put it closed, maybe for someone it works.

RE: BLE not connecting after disconnect

Vidar Berg — Wed, 05 Mar 2025 09:06:31 GMT

When the connectable advertiser was started with bt_le_adv_start(), the bt host will automatically try to resume advertising on disconnect as you don't have the BT_LE_ADV_OPT_ONE_TIME flag set.

Removing the call to advertising_stop(); and advertising_start(); in disconnected() should fix the issue you are seeing with the advetiser not starting after disconnect.

RE: BLE not connecting after disconnect

Zugislav — Wed, 05 Mar 2025 09:04:05 GMT

// Declaring advertising parameters
static struct bt_le_adv_param adv_param = 
{
	.options = BT_LE_ADV_OPT_CONNECTABLE | BT_LE_ADV_OPT_USE_IDENTITY, 	/* Connectable advertising and use identity address */
	.interval_max = BT_GAP_ADV_FAST_INT_MAX_1,							/* 0x30 units, 48 units, 30ms */
	.interval_min = BT_GAP_ADV_FAST_INT_MIN_1,							/* 0x60 units, 96 units, 60ms */
	.peer = NULL														/* Set to NULL for undirected advertising */
};

// Declaring the advertising data
struct bt_data ad[] = {
	BT_DATA_BYTES(BT_DATA_FLAGS, (BT_LE_AD_GENERAL | BT_LE_AD_NO_BREDR)),
	BT_DATA(BT_DATA_NAME_COMPLETE, ble_dev_name, 16),
};

// Declaring the scanning data
struct bt_data sd[] = {
	BT_DATA(BT_DATA_UUID128_ALL, uuid_128, sizeof(uuid_128)),
	BT_DATA(BT_DATA_MANUFACTURER_DATA, manufacturer_data, sizeof(manufacturer_data))
};

/*
	@brief Function for starting advertising.
*/
void advertising_start(void)
{
	if(ble_status == BLE_IDLE){
		int err = bt_le_adv_start(&adv_param, ad, ARRAY_SIZE(ad), sd,
					ARRAY_SIZE(sd));
		
		if (err) {
			LOG_ERR("Advertising failed to start (err %d)", err);
		}
		ble_status = BLE_ADV;
	}
}

RE: BLE not connecting after disconnect

Vidar Berg — Wed, 05 Mar 2025 09:00:01 GMT

This indicates that the advertiser is not re-started on disconnect. Please also post your implementation of advertising_start().

RE: BLE not connecting after disconnect

Zugislav — Tue, 04 Mar 2025 13:45:06 GMT

no, i cannot discover my device on application.

RE: BLE not connecting after disconnect

Vidar Berg — Tue, 04 Mar 2025 13:24:23 GMT

Hello,

Does the device start connectable advertising again after the disconnect? In other words, if you restart scanning in the nRF Connect app after the disconnect, can you still discover your device?

Best regards,

Vidar

RE: BLE not connecting after disconnect

Zugislav — Mon, 03 Mar 2025 14:11:54 GMT

Also security is not enabled, I do not use any security regarding it.

Also this is part of prj.conf file:

# Configure your preferred connection parameters
CONFIG_BT_PERIPHERAL_PREF_MIN_INT=800
CONFIG_BT_PERIPHERAL_PREF_MAX_INT=800
CONFIG_BT_PERIPHERAL_PREF_LATENCY=0
CONFIG_BT_PERIPHERAL_PREF_TIMEOUT=400
CONFIG_BT_GAP_AUTO_UPDATE_CONN_PARAMS=y
CONFIG_BT_SMP_ALLOW_UNAUTH_OVERWRITE=y //this also added to try all

CONFIG_BT_MAX_PAIRED=1

int err= bt_unpair(BT_ID_DEFAULT,BT_ADDR_LE_ANY); this is unpair function not unbond as i mentioned above.