The CH340/CH341 USB driver is essential for communication between your computer and devices like the Ray5 MiniS. If the driver fails to install or work properly, your machine may not be recognized by software such as LightBurn or LaserGRBL.

This guide provides a complete troubleshooting process for both Windows and macOS systems.

I. Windows Systems

1. Common Causes & Solutions

① System Compatibility Issues

• Windows 10/11 usually includes built-in drivers, but auto-install may fail

✅ Solution:

• Manually download the latest driver from the official site:
  • http://www.wch.cn
• Install file: CH341SER.EXE

② Old Driver Conflicts

• Previously installed drivers may block new installations

✅ Solution:

• Open Device Manager → View → Show Hidden Devices
• Expand Ports (COM & LPT)
• Uninstall all CH340/CH341 devices
• ✔ Check “Delete the driver software for this device”
• Reinstall the latest driver

③ Driver Signature Issues (Win7 / Some Win10)

• Windows may block unsigned drivers

✅ Solution:

• Restart → Advanced Startup
• Select Disable Driver Signature Enforcement
• Install the driver again

④ Insufficient Permissions

• Installation requires admin rights

✅ Solution:

• Right-click installer → Run as Administrator

⑤ USB Cable / Port Issues

• Charging-only cables cannot transmit data

✅ Solution:

• Use a data-capable USB cable
• Prefer USB 2.0 ports
• Avoid hubs when possible

2. Confirm Successful Installation

• Plug in the device
• Open Device Manager → Ports (COM & LPT)

✔ Successful:

• USB-SERIAL CH340 (COM3) appears

❌ Failed:

• Yellow warning icon → reinstall or resolve conflicts

3. Alternative Solutions

• Try another computer to rule out system issues
• Use a USB-to-serial adapter (better compatibility):
  • FT232 USB-to-Serial Adapter
  • CP2102 USB-to-Serial Adapter

II. macOS Systems

1. Check if Driver Is Needed

• macOS 10.13+ may auto-detect CH340

Check via Terminal:

✔ If you see:
/dev/tty.wchusbserialxxxx → Driver is already working

2. If Not Recognized → Install Driver

① Download Driver

• Official: https://www.wch.cn/downloads/CH341SER_MAC_ZIP.html
• Recommended (better compatibility):
  • https://github.com/adrianmihalko/ch340g-ch34g-ch34x-mac-os-x-driver

② Allow System Extension

• macOS may block installation

✅ Solution:

• Go to System Settings → Security & Privacy → General
• Click Allow for WCH Electronics Co., Ltd.

③ Restart the Computer

• Required to load the driver properly

3. macOS Troubleshooting

① Driver Installed but No Port

• Run:

• Replug device and check for new port

② Apple Silicon (M1/M2/M3 Macs)

• Official drivers may not be fully compatible

✅ Solution:

• Use the open-source GitHub driver (recommended)

③ Permission Issues (Big Sur / Monterey / Ventura)

• macOS restricts third-party drivers

✅ Advanced Solution:

• Boot into Recovery Mode
• Temporarily disable System Integrity Protection (SIP)
• Install driver, then re-enable SIP

III. Alternative Solutions

If CH340 issues persist:

• Use a native-supported adapter:
  • FTDI USB-to-Serial Adapter (best macOS compatibility)
• Or:
  • Use Wi-Fi connection (if your controller supports it)

Important Notes

• Always use a data USB cable, not charging-only one
• Restart your system after installing drivers
• Ensure only one software accesses the COM port at a time
• Keep drivers updated for stability

Conclusion

CH340 driver installation issues are typically caused by system compatibility, driver conflicts, permission restrictions, or hardware connection problems. By systematically checking drivers, ports, cables, and permissions, most connection issues can be resolved quickly.

For long-term stability—especially on macOS—consider using alternative USB-to-serial adapters with native support.

To make sure your Longer laser engraver works with your computer, check that the CH340 driver is installed and working well. If not, please download and install the appropriate driver for your device.

Step 1: Check the CH340 Driver Installation

• A. The connection issue may occur if the required CH340 driver is missing or improperly installed.

• B. For macOS 10.15 or later, the CH340 driver is already built-in and does not require manual installation.

• C. If installation is needed, download the driver package from the link below:
  👉 CH340 Driver Download

Video Tutorials:

• How to Install CH340 Driver for LightBurn on macOS Sequoia

• How to Install CH340 Driver for LightBurn on macOS

Step 2: Verify COM Port Detection

For Windows Users

1. Connect your Longer laser engraver to your PC using the included USB cable.

2. Download and install the CH340 driver. The installation may prompt you to restart your computer.

3. Follow the on-screen instructions to complete installation.If any error messages appear, please contact Longer technical support for assistance.

4. To confirm successful installation:

Right-click This PC, select Manage → Device Manager → Ports (COM & LPT).

If you see CH340 listed under COM ports, the system has successfully recognized your device.

For macOS Users

1. Connect your laser engraver to your Mac via the provided USB cable.

2. Download and install the CH340 driver. You may need to reboot the system.

   • If installation errors occur, contact Longer technical support.

3. After restarting, go to:
   System Preferences → Security & Privacy → General → Allow

   • Approve the CH340 driver installation when prompted (you may need to restart again).

   • Reconnect your laser engraver. Now LaserBurn, LightBurn, or LaserGRBL should automatically detect your device.

     

   • If the “Allow” button does not respond, follow the terminal method below.

Step 3: Load the Driver Manually via Terminal

1. Open Terminal:
   Finder → Applications → Utilities → Terminal

2. Copy and paste the following command:

   
   

   sudo kextload /Library/Extensions/usbserial.kext/

3. Press Enter. If prompted, enter your Mac user password, then press Enter again.

   

4. Once the command executes successfully, you will see a confirmation message in the Terminal window.

After completing these steps, your system should recognize the Longer laser engraver correctly. You can now connect and control your device through LaserBurn, LightBurn, or LaserGRBL without connection errors.

For Windows, right-click the computer and select Manage, click Device Manager, click to expand Ports, find the port corresponding to the CH340 driver. Run the MKSLaserTool and click MKS ESP32 Download Tool, select the right port which is corresponding to CH340 driver and the update firmware. Set baud to 25000, Flash size to 8MB, and select ESP32 S3, click Start, it will prompt firmware successfully flashed after the update is completed.

1) Update by MKSLaserTool software

Please download LaserTool from https://github.com/LONGER3D/Longer-Laser and install it. Connect the laser engraver to computer with Type C cable, turn on the engraver. 

2) Update by ESPTool Web

Enter https://espressif.github.io/esptool-js/ in the browser. This webpage can connect to the serial port to flash the firmware online.Select the baud rate 115200 and connect to the CH340 serial port, then Click “Erase Flash” first, then enter the Flash address 0x0 and select the firmware, then click Program to start burning. 

3) Update by LaserBurn APP

After the engraving machine is connected to the LaserBurn App, click Me→About→Firmware Update→RAY5 mini to upgrade the firmware.

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