Can’t connect to machine or jog


In order to connect to the machine and get it to move, several things need to happen:

  • (For Windows) The drivers must be properly installed (this is done by installing Carbide Motion: )
  • Grbl must be properly installed and configured (normally it comes pre-installed, but mistakes happen and it is possible for the installation to become corrupt)
  • The machine must be connected with a good quality USB cable (some people have found that one with ferrite beads makes for a more reliable connection)
  • The machine must be connected to a power source and if there is a switch, switched on. (Please check your power supply and ensure that if there is a physical switch, it is set to match your local power standard before plugging it in.)
  • (If this is an option) The communications / control software must be set to use the correct communications port (you may want to check the list of available ports and note which ones are present before installation) and be set to the correct speed (115200 baud for current versions of Grbl) if your system allows for such settings

Order Matters

It is suggested that one connects to the machine in the sequence suggested on the Operating Checklist:

Machine Operating Checklist

  • power up the computer (it should boot up)
  • connect the USB cable (the computer should indicate that a device has been attached)
  • turn on power for the machine (the power supply should light up, motors should lock, and if installed, the fan should come on)
  • wait until the micro-controller boots up (early versions would draw power over the USB connection to run the Arduino, but this is no longer the case), and lights will flash at first, then glow steadily once booted up)
  • start the comm/control program (it should launch and display a window which will allow one to connect to the machine)
  • open the connection to the machine (it should connect and afford one control)


If that doesn’t work properly, then it should be a straight-forward matter to determine the difficulty:

  • check the power
  • check the USB cable and USB port — try a different USB port (or machine) if possible. Be certain to power down completely as a part of testing. 
    • On Macs, resetting the PRAM (command option p r when rebooting) and resetting the System Management Chip (check Apple’s support page for your system) has helped on some systems — presumably where there was a problem with the USB system. 
    • For Windows, uninstalling and reinstalling the driver may help.
    • For both systems, uninstalling and reinstalling the application may address problems, or if possible, try a different machine.

Next Step

Please contact and we’ll get your machine moving.



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