LoRa Humidity Sensor Main

int main (void)
{
    lorawan_status_t retcode;                                                   //Stores the status of a call to LoRaWAN protocol
    if (lorawan.initialize(&ev_queue) != LORAWAN_STATUS_OK) {                   //Initialize LoRaWAN stack
        pc.printf("[ERROR] LoRa initialization failed! \r\n");
        return -1;
    }
    pc.printf("Mbed LoRaWANStack initialized \r\n");

    callbacks.events = mbed::callback(lora_event_handler);                      //Prepare application callbacks
    lorawan.add_app_callbacks(&callbacks);

    if (lorawan.set_confirmed_msg_retries(CONFIRMED_MSG_RETRY_COUNTER)          //Set number of retries in case of CONFIRMED messages
            != LORAWAN_STATUS_OK) {
        pc.printf("[ERROR] set_confirmed_msg_retries failed! \r\n\r\n");
        return -1;
    }
    pc.printf("CONFIRMED message retries : %d \r\n",
              CONFIRMED_MSG_RETRY_COUNTER);

    if (lorawan.enable_adaptive_datarate() != LORAWAN_STATUS_OK) {              //Enable adaptive data rate
        pc.printf("[ERROR] enable_adaptive_datarate failed! \r\n");
        return -1;
    }
    pc.printf("Adaptive data  rate (ADR) - Enabled \r\n");

    retcode = lorawan.connect();

    if (retcode == LORAWAN_STATUS_OK ||
            retcode == LORAWAN_STATUS_CONNECT_IN_PROGRESS) {
    } else {
        pc.printf("[ERROR] Connection error, code = %d \r\n", retcode);
    }

    pc.printf("Connection - In Progress ...\r\n");

    uint32_t val;

    while(1) {
        val = get_hum();
        pc.printf("Read humidity value: %i \r\n", val);

        ev_queue.dispatch();

        wait_ms(30000);
    }
    return 0;
}