Unable to connect to Lightburn or LaserGRBL for Nano

Introduction

If your LONGER Nano Series laser engraver cannot connect to LightBurn or LaserGRBL, or your computer does not recognize the machine, the issue is usually related to the USB connection, driver installation, software configuration, or communication settings.

A stable connection requires:

• A proper USB data cable
• Correct driver installation
• The correct COM port selection
• Compatible software settings

This guide provides step-by-step solutions to help you quickly identify and solve common connection problems with the Nano Series.

1. Wrong Type-C Cable

Ensure you are using a data cable, not a charging-only cable.

Fix:

• Connect the cable to the third port on the engraver
• Try a different USB data cable if needed

2. Cannot Find CH340 / GH430 Driver

If the driver is not installed, the computer cannot detect the machine.

Windows:

• Right-click This PC → Manage → Device Manager
• Expand Ports (COM & LPT)
• Find the CH340 port
• Select this COM port in LightBurn under “(Choose)”

macOS:

• Go to About This Mac → System Report → USB
• Look for USB Serial
• In LightBurn, select the port (e.g. cu.wchusbserial…)

If no port appears:

• Check USB connection and power
• Install the CH340 driver
• Installation tutorial:

3. Port Already in Use

The CH340 port may be occupied by other software.

Fix:

• Close programs like serial tools, Cura, etc.
• Reconnect the machine and try again

4. Configuration File Not Imported or Damaged

LaserGRBL:

• Right-click the bottom area → Import Custom Buttons
• Import LaserNano.zbn file
• Confirm to add Nano, Slide, Rotary functions

LightBurn:

• Click Devices → Import
• Select Nano Pro.lbdev
• Finish setup to load the device and macros

5. Incorrect Baud Rate

An incorrect baud rate will prevent connection.

Fix:

• Set baud rate to 961200
• LaserGRBL: Select COM port + set 961200