add timer in ble_app_uart

[yiran]

I am working on adding a timer in the ble_app_uart sample, aiming on disconnect with device which doesn't send any data in specific time, such as 5 seconds.

Now I have found an example "timer_pca10028", and try to insert useful part into my application. here is my mofified main function:

int main(void)
{
    uint32_t err_code;
    bool erase_bonds;
    uint8_t  start_string[] = START_STRING;
    
    // Initialize.
    APP_TIMER_INIT(APP_TIMER_PRESCALER, APP_TIMER_MAX_TIMERS, APP_TIMER_OP_QUEUE_SIZE, false);
    uart_init();
    buttons_leds_init(&erase_bonds);
    ble_stack_init();
    gap_params_init();
    services_init();
    advertising_init();
    conn_params_init();
    
    printf("%s",start_string);

		err_code = nrf_drv_timer_init(&TIMER_LED, NULL, timer_data_receive_event_handler);
    //APP_ERROR_CHECK(err_code);
    
		uint32_t time_ticks;
    time_ticks = nrf_drv_timer_ms_to_ticks(&TIMER_LED, DATA_RECEIVE_TIMEOUT);
    
    nrf_drv_timer_extended_compare(
         &TIMER_LED, NRF_TIMER_CC_CHANNEL0, DATA_RECEIVE_TIMEOUT, NRF_TIMER_SHORT_COMPARE0_CLEAR_MASK, true);
    
		err_code = ble_advertising_start(BLE_ADV_MODE_FAST);
    APP_ERROR_CHECK(err_code);
    // Enter main loop.
    for (;;)
    {
        power_manage();
    }
}

timer_data_receive_event_handler is my timer event handler, when I find the time is out and it doesn't get any message, 51822 terminates connection, :

void timer_data_receive_event_handler(nrf_timer_event_t event_type, void* p_context)
{ 
    switch(event_type)
    {
				uint32_t  err_code;
        case NRF_TIMER_EVENT_COMPARE0:
						if (!is_received_data){
							err_code = sd_ble_gap_disconnect(m_conn_handle, BLE_HCI_CONN_INTERVAL_UNACCEPTABLE);
							APP_ERROR_CHECK(err_code);
							nrf_drv_timer_disable(&TIMER_LED);
						}
            
            break;
        default:
            //Do nothing.
            break;
    }    
}

is_received_data is used for marking if I have received the data in nus_data_handler()

when the connection is established, I will start a timer like that:

static void on_ble_evt(ble_evt_t * p_ble_evt)
{
    uint32_t                         err_code;
    
    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_conn_handle = p_ble_evt->evt.gap_evt.conn_handle;
						printf("%s","Device Connected:");
						nrf_drv_timer_enable(&TIMER_LED);
            break;
            ...
            ...

Now I have two problem:

1. Does the sample "timer_pca10028" match my purpose? Can I set a timer imitating the sample code?
2. nrf_drv_timer_enable(&TIMER_LED) in on_ble_evt cause the disconnection with mobile phone. If I remove this line, my application works as a normal ble_app_uart application at least. However when I enable it, the nrf UART app connects to the 51822 and disconnect automatically at the same time. But the LED on the dongle shows it is in a connected mode.

Could anyone help me? Thanks in advance!