/* Function for handling the BLE_GATTS_EVT_WRITE event from the S110 SoftDevice.  */
static void on_write(ble_nus_t *p_nus, ble_evt_t *p_ble_evt)
/* Function for handling the BLE_GATTS_EVT_WRITE event from the S110 SoftDevice.  */
static void on_write(ble_nus_t *p_nus, ble_evt_t *p_ble_evt)
{
    ble_gatts_evt_write_t * p_evt_write = &p_ble_evt->evt.gatts_evt.params.write;
    if (
        (p_evt_write->handle == p_nus->rx_handles.cccd_handle)
        &&
        (p_evt_write->len == 2)
       )
    {
        if (ble_srv_is_notification_enabled(p_evt_write->data))
        {
            p_nus->is_notification_enabled = true;
        }
        else
        {
            p_nus->is_notification_enabled = false;
        }
    }
    else if (
             (p_evt_write->handle == p_nus->tx_handles.value_handle)
             &&
             (p_nus->data_handler != NULL)
            )
    {
        p_nus->data_handler(p_nus, p_evt_write->data, p_evt_write->len);
    }
    else
    {
    }
}