esp32 uart interrupt

void uartSetup(void)
{
  /* Configure parameters of an UART driver,
    * communication pins and install the driver */
    uart_config_t uart_config = {
        .baud_rate = 19200,
        .data_bits = UART_DATA_8_BITS,
        .parity = UART_PARITY_DISABLE,
        .stop_bits = UART_STOP_BITS_1,
        .flow_ctrl = UART_HW_FLOWCTRL_DISABLE
    };

    ESP_ERROR_CHECK(uart_param_config(EX_UART_NUM, &uart_config));
    //Set UART pins
    ESP_ERROR_CHECK(uart_set_pin(EX_UART_NUM, GPIO_NUM_5, GPIO_NUM_17, UART_PIN_NO_CHANGE, UART_PIN_NO_CHANGE));

    //Install UART driver, and get the queue.
    ESP_ERROR_CHECK(uart_driver_install(EX_UART_NUM, BUF_SIZE * 2, 0, 0, NULL, 0));

    // release the pre registered UART handler/subroutine
    ESP_ERROR_CHECK(uart_isr_free(EX_UART_NUM));

    // register new UART subroutine
    ESP_ERROR_CHECK(uart_isr_register(EX_UART_NUM,uart_intr_handle, NULL, ESP_INTR_FLAG_IRAM, &handle_console));

    // enable RX interrupt
    ESP_ERROR_CHECK(uart_enable_rx_intr(EX_UART_NUM));
    log_d("interrupt enabled");
}


/*
 * Define UART interrupt subroutine to ackowledge interrupt
 */
static void IRAM_ATTR uart_intr_handle(void *arg)
{
  uint16_t rx_fifo_len, status;
  uint8_t i=0;

  status = UART2.int_st.val; // read UART interrupt Status
  rx_fifo_len = UART2.status.rxfifo_cnt; // read number of bytes in UART buffer

  while(rx_fifo_len){
   rxbuf[i] = UART2.fifo.rw_byte; // read all bytes
   rx_fifo_len--;
   ESP_ERROR_CHECK(uart_disable_rx_intr(EX_UART_NUM));
   Serial.print(rxbuf[i++]);
  }
  // after reading bytes from buffer clear UART interrupt status
  uart_clear_intr_status(EX_UART_NUM, UART_RXFIFO_FULL_INT_CLR|UART_RXFIFO_TOUT_INT_CLR);
  //Serial.write(rxbuf,77);
  for (int i = 33; i <= 48; i++)
  {
    pacemakerID[i-33] = rxbuf[i];
  }
  byte byteID[7] ={pacemakerID[2],pacemakerID[3],pacemakerID[6],pacemakerID[7],pacemakerID[13],pacemakerID[14],pacemakerID[15]};

  String tmpPacemakerID = String((char*)byteID);
  uint32_t deviceID = tmpPacemakerID.toInt();
  DeviceInfo = true;
  //Serial.write(pacemakerID,16);
  //Serial.println("");
  //Serial.write(devID,4);
  devID[3] = (deviceID >> 24) & 0xFF;
    devID[2] = (deviceID >> 16) & 0xFF;
    devID[1] = (deviceID >> 8) & 0xFF;
    devID[0] = deviceID & 0xFF;
  //Serial.write(devID,4);
  //Serial.println(base64::encode(&pacemakerID[0],16));
  // a test code or debug code to indicate UART receives successfully,
  log_d("rx done!");
  Serial.write(rxbuf,rx_fifo_len);
  ESP_ERROR_CHECK(uart_disable_rx_intr(EX_UART_NUM));
}