Connecting to the engraver

Step 1: ensure COM port is recognized by the OS

Is it necessary that your Windows OS recognize your engraver as a serial COM port once connected. 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.

How to Install CH340 Drivers - learn.sparkfun.com

The name with which it appears in the device manager strictly depends on the type of machine.

If no name appears, or if a device with an error symbol appears, you probably need to install a driver. Refer to the manufacturer’s instructions to find out which driver to install.

Step by Step Installation guide for CH340g USB to serial IC along with its  drivers

Usually the most common controller board use the CH340 chip.
Google for “arduino CH340G” if your system does not recognize serial port.

Is it also possible to install CH340 driver with LaserGRBL from “Tools” menu:

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.

Step 2: connect with LaserGRBL

LaserGRBL constantly checks for COM ports available on the machine. The list of ports allows you to select the COM port which your control board is connected on.

This port number is the same shown near the COM port in device manager.

Please select the proper baud rate for the connection according to your machine firmware configuration. Most common speed is 115200, older controller sometime use 57600.

Connection config

When connected to proper port grbl reply with “welcome message” showing Grbl firmware version.

Connection response

On the bottom-right of the LaserGRBL interface you should read “Status: Idle”

If you see “Disconnected” or “Connecting” but no message come from the engraver, maybe you should change something in your COM port configuration.

Note that LaserGRBL only recognizes engraver that use the standard GRBL protocol, and cannot connect to other type of protocols.

If you see “Status: Alarm” it means that your board is in an alarm state. The machine is connected, and this state comes from the machine: it does not indicate a LaserGRBL problem.

Usually when the machine is in Alarm status it is necessary to execute the homing procedure (if the machine is equipped with mechanical limit switches) or simply press the padlock button to acknowledge the alarm.