Hi there,
Currently, I am working on a project which uses iphone(or other IOS device) as a central, and nrf51822 as peripheral. Basically, the concept is that peripheral device stays in a fixed position, and according to the connection to central(iphone) device, peripheral device will activate/deactivate some functions. For example, when iPhone (central) closer, it(peripheral) turn on LED light, when iPhone(central) leave, it(peripheral) switch LED off.
I've tried to implement this service in Ble_peripheral -> ble_app_proximity (when in case BLE_LLS_EVT_LINK_LOSS_ALERT, switching on/off the LED).
I have few questions regarding to this project and hope someone can help me:
- I put segger_rtt_writestring() in on_lls_evt(ble_lls_t * p_lls, ble_lls_evt_t * p_evt), and in case: BLE_LLS_EVT_LINK_LOSS_ALERT; and also in on_bas_evt(ble_bas_t * p_bas, ble_bas_evt_t *p_evt), in case: BLE_GAP_EVT_CONNECTED and BLE_GAP_EVT_DISCONNECTED
static void on_lls_evt(ble_lls_t * p_lls, ble_lls_evt_t * p_evt) { switch (p_evt->evt_type) { case BLE_LLS_EVT_LINK_LOSS_ALERT: alert_signal(p_evt->params.alert_level); // write a call function!
SEGGER_RTT_WriteString(0," LINK LOSS ALERT!!!\r\n");
//call_func();
break;
default:
// No implementation needed.
break;
}
} and
static void on_ble_evt(ble_evt_t * p_ble_evt) { uint32_t err_code = NRF_SUCCESS;
switch (p_ble_evt->header.evt_id)
{
case BLE_GAP_EVT_CONNECTED:
err_code = bsp_indication_set(BSP_INDICATE_CONNECTED);
APP_ERROR_CHECK(err_code);
m_advertising_mode = BLE_NO_ADV;
m_conn_handle = p_ble_evt->evt.gap_evt.conn_handle;
// call the function
SEGGER_RTT_WriteString(0," GAP_connected!!!\r\n"); // *****************
break;
case BLE_GAP_EVT_DISCONNECTED:
err_code = bsp_indication_set(BSP_INDICATE_IDLE);
APP_ERROR_CHECK(err_code);
m_conn_handle = BLE_CONN_HANDLE_INVALID;
SEGGER_RTT_WriteString(0," GAP_disconnected!!!\r\n"); // *****************
advertising_start();
break;
----
}
I noticed that: (In JlinkRTTClient) Once I connect to the service, it will output: LINK LOSS ALERT!!! GAP_connected!!! If I disconnect by myself, it will output only: GAP_disconnected!!
If the central and peripheral are disconnected due to the "far distance", it will output: LINK LOSS ALERT!!! GAP_disconnected!!!
I am wondering the reason behind this, is that case BLE_LLS_EVT_LINK_LOSS_ALERT mainly used for distinguish the disconnected between "manually" and "cause by distance"?
- second question
My second question is that in order to achieve the task(automatically re-connect), has anyone any suggestion? Following is my idea: In the beginning, I manually connect the devices (my iPhone and the peripheral), and after iPhone outside the reachable distance, the "case BLE_LLS_EVT_LINK_LOSS_ALERT" will call a function to turn off the LED. And after I comeback (closer at certain range), they will automatically re-connect and switch on the LED again!
Also, in terms of energy consumption, will this idea waste power due to the peripheral tries to detect is the iPhone within a certain range all the time?
I am a beginner, if anyone has the any solution or suggestion please kindly inform me :)
Best,
