# Burning


## Mini and Small Systems


### "Error: Opening COMxx: Access denied" Displayed When I Start Burning

- **Symptom**
  
  After I click **Burn** and select a serial port, **Error: Opening COMxx: Access denied** is displayed.

  **Figure 1** Access denied error
  
  ![failed-to-open-the-serial-port](figures/failed-to-open-the-serial-port.png)
- **Possible Causes**
  
  The serial port is in use.

- **Solution**

  1. Search for the terminal using serial-xx from the drop-down list in the **TERMINAL** panel.

     **Figure 2** Checking whether the serial port is in use
     
     ![en-us_image_0000001243481989](figures/en-us_image_0000001243481989.png)
  
  2. Click the dustbin icon as shown below to disable the terminal using the serial port.
  
     **Figure 3** Disabling the terminal using the serial port
     
     ![en-us_image_0000001243082093](figures/en-us_image_0000001243082093.png)

  3. Click **Burn**, select the serial port, and start burning images again.
  
     **Figure 4** Restarting the burning task
     
     ![en-us_image_0000001198322224](figures/en-us_image_0000001198322224.png)


### The Image Failed To Be Burnt

- **Symptom**
  
  The image failed to be burnt over a serial port.

- **Possible Causes**
  
  The DevEco Device Tool plug-in is not restarted after being installed.

- **Solution**
  
  Restart DevEco Device Tool.


### No Command Output Is Displayed

- **Symptom**
  
  The serial port shows that the connection has been established. After the board is restarted, nothing is displayed when I press **Enter**.

- **Possible Cause 1**
  
  The serial port is connected incorrectly.

- **Solution**
  
  Change the serial port number.

  Start **Device Manager** to check whether the serial port connected to the board is the same as that connected to the terminal device. If the serial ports are different, perform step 1 in the **Running an Image** section to change the serial port number.

- **Possible Cause 2**
  
  The U-Boot of the board is damaged.

- **Solution**
  
  Burn the U-Boot.

  If the fault persists after you perform the preceding operations, the U-Boot of the board may be damaged. In this case, burn the U-Boot by performing the following steps:

   1. Obtain the U-Boot file.
      > ![icon-notice.gif](public_sys-resources/icon-notice.gif) **NOTICE**
      > The U-Boot file of the two boards can be obtained from the following paths, respectively.
      > 
      > Hi3516D V300: **device\hisilicon\hispark_taurus\sdk_liteos\uboot\out\boot\u-boot-hi3516dv300.bin**
      > 
      > Hi3518E V300: **device\hisilicon\hispark_aries\sdk_liteos\uboot\out\boot\u-boot-hi3518ev300.bin**

	2. Burn the U-Boot file by following the procedures for burning a U-Boot file over USB.
       Select the U-Boot files of the corresponding development board for burning by referring to [Burning to Hi3516D V300](../quick-start/quickstart-ide-lite-steps-hi3516-burn.md).

	3. Log in to the serial port after the burning is complete.

       **Figure 5** Information displayed through the serial port after the U-Boot file is burnt

       ![en-us_image_0000001243484907](figures/en-us_image_0000001243484907.png)


### Windows-based PC Failed to Be Connected to the Board

- **Symptom**
  

  The file image cannot be obtained after clicking **Burn** and selecting a serial port.

  **Figure 6** Failed to obtain the file image due to network disconnection

  ![en-us_image_0000001198322428](figures/en-us_image_0000001198322428.png)

- **Possible Causes**
  

  The board is disconnected from the Windows-based PC.

  Windows Firewall does not allow Visual Studio Code to access the network.

- **Solution**

  1. Check whether the network cable is properly connected.
  2. Click **Windows Firewall**.

	   **Figure 7** Setting the firewall
     ![en-us_image_0000001198162584](figures/en-us_image_0000001198162584.png)

  3. Click **Firewall & network protection**. On the displayed page, click **Allow an app through the firewall**.

     **Figure 8** Firewall & network protection
     ![en-us_image_0000001198323146](figures/en-us_image_0000001198323146.png)

  4. Select Visual Studio Code.

     **Figure 9** Selecting Visual Studio Code
     ![en-us_image_0000001198003232](figures/en-us_image_0000001198003232.png)

  5. Select the **Private** and **Public** network access rights for Visual Studio Code.

     **Figure 10** Allowing Visual Studio Code to access the network
     ![en-us_image_0000001243084579](figures/en-us_image_0000001243084579.png)