Machine status

Machine statusMeaning
DisconnectedLaserGRBL is not connected to your engraver
ConnectingLaserGRBL is waiting for your machine to reply
IdleEngraver connected and ready to receive command
RunEngraver is executing some command
HoldEngraver is paused (usually because pressing hold button)
DoorSafety door is opened (for machine equiped with safety door)
HomeEngraver is performing homing procedure
AlarmEngraver is in alarm state (see below)
CheckCheck mode is active (read more)
JogEngraver is performing a jog command (read more)
Queuenot documented?
CoolingEngraver is performing a cooling pause during job

Alarm state

When machine is in Alarm State you should carefully read on left side of LaserGRBL to understand why machine is in alarm (alarm cause).

When the machine is in an alarm state it is unable to receive any command, for this reason almost all the buttons of LaserGRBL are disabled.

Normally it is possible to exit the alarm state using the “$X (Unlock)” command or by carrying out the “$H (Homing)” procedure – for machines equipped with limit switches.

In more serious cases, however, it is necessary to use the reset button.

Most common alarm cause and messages

CauseMeaning and solution
Homing FailMachine is configured to require homing before use: please execute homing procedure using “$H (Homing)” button.

If homing fail (ie. limit switches cannot be sensed) the “Homing Fail”error is raised again.

If you don’t have limit switches or you don’t want to use them, you can disable homing by setting $22=0
Soft LimitSoft limits is a safety feature to help prevent your machine from traveling too far and beyond the limits of travel, crashing or breaking something expensive.
It works by knowing the maximum travel limits for each axis and where laser is.

Whenever a motion command is sent the control board check whether or not you accidentally have exceeded your machine space.

If you do, Grbl will issue an immediate feed hold, and then set the system alarm indicating the problem.

If you have issue with soft limits please check your machine size is properly configured or disable soft limit check.
Hard LimitHard limit work basically the same as soft limits, but use physical switches instead. Basically you wire up some switches (mechanical, magnetic, or optical) near the end of travel of each axes, or where ever you feel that there might be trouble if your program moves too far to where it shouldn’t. When the switch triggers, it will immediately halt all motion, shutdown the coolant and spindle (if connected), and go into alarm mode, which forces you to check your machine and reset everything.

If you have issue with hard limits you can always disable this feature.
Travel ExceededSame as Soft Limit
Other alarmsSome engraver could generate specific alarm like flame alarm, shock and movement alarm, exposure alarm etc. It is recommended to investigate these alarms in the manual provided by the manufacturer of your engraver.