# FAQ on Hi3518 - [What should I do when the images failed to be burnt over the selected serial port?](#section1498892119619) - [What should I do when Windows-based PC failed to be connected to the board?](#section8512971816) - [What should I do when the image failed to be burnt?](#section1767804111198) - [What should I do when the message indicating Python cannot be found is displayed during compilation and building?](#en-us_topic_0000001053466255_section1039835245619) - [What should I do when no command output is displayed?](#en-us_topic_0000001053466255_section14871149155911) ## What should I do when the images failed to be burnt over the selected serial port? - **Symptom** **Error: Opening COMxx: Access denied** is displayed after clicking **Burn** and selecting a serial port. **Figure 1** Failed to open the serial port ![](figures/failed-to-open-the-serial-port.png "failed-to-open-the-serial-port") - **Possible Causes** The serial port has been used. - **Solutions** 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 used ![](figures/checking-whether-the-serial-port-is-used.png "checking-whether-the-serial-port-is-used") 2. Click the dustbin icon as shown in the following figure to disable the terminal using the serial port. **Figure 3** Disabling the terminal using the serial port ![](figures/disabling-the-terminal-using-the-serial-port.png "disabling-the-terminal-using-the-serial-port") 3. Click **Burn**, select the serial port, and start burning images again. **Figure 4** Restarting burning ![](figures/changjian1.png) ## What should I do when 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 5** Failed to obtain the image file due to unavailable connection ![](figures/failed-to-obtain-the-image-file-due-to-unavailable-connection.png "failed-to-obtain-the-image-file-due-to-unavailable-connection") - **Possible Causes** The board is disconnected from the Windows-based PC. Windows Firewall does not allow Visual Studio Code to access the network. - **Solutions** 1. Check whether the network cable is properly connected. 2. Click **Windows Firewall**. **Figure 6** Network and firewall setting ![](figures/network-and-firewall-setting.png "network-and-firewall-setting") 3. Click **Firewall & network protection**, and on the displayed page, click **Allow applications to communicate through Windows Firewall**. **Figure 7** Firewall and network protection ![](figures/firewall-and-network-protection.png "firewall-and-network-protection") 4. Select the Visual Studio Code application **Figure 8** Selecting the Visual Studio Code application ![](figures/selecting-the-visual-studio-code-application.png "selecting-the-visual-studio-code-application") 5. Select the **Private** and **Public** network access rights for the Visual Studio Code application. **Figure 9** Allowing the Visual Studio Code application to access the network ![](figures/allowing-the-visual-studio-code-application-to-access-the-network.png "allowing-the-visual-studio-code-application-to-access-the-network") ## What should I do when the image failed to be burnt? - **Symptom** The burning status is not displayed after clicking **Burn** and selecting a serial port. - **Possible Causes** The IDE is not restarted after the DevEco plug-in is installed. - **Solutions** Restart the IDE. ## What should I do when the message indicating Python cannot be found is displayed during compilation and building? - **Symptom** ![](figures/en-us_image_0000001058781525.png) - **Possible Cause 1** Python is not installed. - **Solutions** Install the Python environment by referring to [Installing a Python Environment](basic-os-environment-setup.md#section11255767343). - **Possible Cause 2** ![](figures/en-us_image_0000001058939672.png) - **Solutions** Run the following commands: ``` # cd /usr/bin/ # which python3 # ln -s /usr/local/bin/python3 python # python --version ``` Example: ![](figures/en-us_image_0000001058781464.png) ## What should I do when 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 you press **Enter**. - **Possible Cause 1** The serial port is connected incorrectly. - **Solutions** 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](developing-the-first-example-program-running-on-hi3518.md#li744118533233) in the **Running an Image** section to change the serial port number. - **Possible Cause 2** The U-boot of the board is damaged. - **Solutions** Burn the U-boot. If the fault persists after you perform the preceding operations, the U-boot of the board may be damaged. You can burn the U-boot by performing the following steps: 1. Obtain the U-boot file. >![](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 corresponding development boards for burning by referring to [Programming Flash Memory on the Hi3516](https://device.harmonyos.com/en/docs/ide/user-guides/hi3516_upload-0000001052148681)/[Programming Flash Memory on the Hi3518](https://device.harmonyos.com/en/docs/ide/user-guides/hi3518_upload-0000001057313128) 3. Log in to the serial port after the burning is complete. ![](figures/en-us_image_0000001058719409.png)