Always reconnect after peers deleted

[Borden]

Hi community,

I'm working on a BLE gamepad with custom board based on 51802 and s130, code modified from ble_app_hids_keyboard. The gamepad works like a charm on my Android phone, but I found there's a strange problem with reconnecting.

If I hold a specific button down while power up, the gamepad deletes all peers, just like the keyboard example does, but I don't know why, it still reconnect to my phone automatically, no matter whether peers were deleted. The only way to unbond to the phone is to delete bond from the phone side. I've tried several phones and several boards, all same results. Is that suppose to happen?

My pm init code is:

#define SEC_PARAM_BOND					1
#define SEC_PARAM_MITM					0
#define SEC_PARAM_LESC					0
#define SEC_PARAM_KEYPRESS				0
#define SEC_PARAM_IO_CAPABILITIES		BLE_GAP_IO_CAPS_NONE
#define SEC_PARAM_OOB					0
#define SEC_PARAM_MIN_KEY_SIZE			7
#define SEC_PARAM_MAX_KEY_SIZE			16

memset(&sec_param, 0, sizeof(ble_gap_sec_params_t));
>
// Security parameters to be used for all security procedures.
sec_param.bond			= SEC_PARAM_BOND;
sec_param.mitm			= SEC_PARAM_MITM;
sec_param.lesc			= SEC_PARAM_LESC;
sec_param.keypress		= SEC_PARAM_KEYPRESS;
sec_param.io_caps		= SEC_PARAM_IO_CAPABILITIES;
sec_param.oob			= SEC_PARAM_OOB;
sec_param.min_key_size	= SEC_PARAM_MIN_KEY_SIZE;
sec_param.max_key_size	= SEC_PARAM_MAX_KEY_SIZE;
sec_param.kdist_own.enc	= 1;
sec_param.kdist_own.id	= 1;
sec_param.kdist_peer.enc = 1;
sec_param.kdist_peer.id	= 1;
err_code = pm_sec_params_set(&sec_param);
APP_ERROR_CHECK(err_code);

the adv init code is:

void advertising_init(void)
{
	uint32_t				err_code;
	uint8_t					adv_flags;
	ble_advdata_t			advdata;
	ble_adv_modes_config_t	options;
	// Build and set advertising data
	memset(&advdata, 0, sizeof(advdata));

	adv_flags						= BLE_GAP_ADV_FLAGS_LE_ONLY_GENERAL_DISC_MODE;
	advdata.name_type				= BLE_ADVDATA_FULL_NAME;
	advdata.include_appearance		= true;
	advdata.flags					= adv_flags;
	advdata.uuids_complete.uuid_cnt	= sizeof(m_adv_uuids) / sizeof(m_adv_uuids[0]);
	advdata.uuids_complete.p_uuids	= m_adv_uuids;

	memset(&options, 0, sizeof(options));
	options.ble_adv_whitelist_enabled		= false;
	options.ble_adv_directed_enabled		= true;
	options.ble_adv_directed_slow_enabled	= false;
	options.ble_adv_directed_slow_interval	= 0;
	options.ble_adv_directed_slow_timeout	= 0;
	options.ble_adv_fast_enabled			= true;
	options.ble_adv_fast_interval			= APP_ADV_FAST_INTERVAL;
	options.ble_adv_fast_timeout			= APP_ADV_FAST_TIMEOUT;
	options.ble_adv_slow_enabled			= false;
	options.ble_adv_slow_interval			= APP_ADV_SLOW_INTERVAL;
	options.ble_adv_slow_timeout			= APP_ADV_SLOW_TIMEOUT;

	err_code = ble_advertising_init(&advdata,
								NULL,
								&options,
								on_adv_evt,
								ble_advertising_error_handler);
	APP_ERROR_CHECK(err_code);
}

Thanks in advance.

[Alex]

It is expected behavior. Android remembers bonding information and automatically tries to connect to BLE device. Then BLE device accepts connection. If you want to stop that connection then either delete bonding information from Android or somehow reject any connection you don't want. As I mentioned Whitelist will reject unwanted connections.

[Borden]

​ Oh I see now, turn out the phone is in the leading role:

• if the phone has bonding info but my device hasn't, they will connect anyway;
• if the phone has no bonding info but my device has, repairing will be rejected.

So based on my usage scenario, I'd like to reverse it. For the latter situation, I think I know how to handle, as you said, just don't reject the pairing request, in the case PM_EVT_CONN_SEC_CONFIG_REQ, right? But for the former situation, I still don't know how to let them not to reconnect, since in that situation the WL is empty, my device have no idea if the connection request is from the last host.

Now I've thought this through, what I really want is, in a situation a new host which my device has no bond info about, send a connection request, if the host has no bond info of my device either, accept it; if the host has, that means I have deleted bond info from the device, then reject it. Is this possible?

BTW I'm using SDK12, s130v2.