Please note: although most of the engraver use the CH340 driver there are some models that do not use it: refer to the manufacturer’s instructions to find out which driver to install. Is it also possible to install CH340 driver with LaserGRBL from “Tools” menu: Google for “ arduino CH340G” if your system does not recognize serial port. Usually the most common controller board use the CH340 chip. Refer to the manufacturer’s instructions to find out which driver to install. If no name appears, or if a device with an error symbol appears, you probably need to install a driver. The name with which it appears in the device manager strictly depends on the type of machine. Depending on the type of controller board this port may appear in the computer’s device manager with the name “USB-SERIAL CH340” or “USB Serial Device” or something else.

Is it necessary that your Windows OS recognize your engraver as a serial COM port once connected. Step 1: ensure COM port is recognized by the OS

Ch340 driver