Alarm codes

These are the alarms that get raised when the system encounters some issues, for example if your pull off distance for the limit switches $27 is set too small, you get an ‘8’ Alarm. Just increase the pull off distance to say $27=4 (4 mm) and try homing again.

Alarm Code Alarm Message Alarm Description
1Hard limitHard limit has been triggered. Machine position is likely lost due to sudden halt. Re-homing is highly recommended.
2Soft limitSoft limit alarm. G-code motion target exceeds machine travel. Machine position retained. Alarm may be safely unlocked.
3Abort during cycleReset while in motion. Machine position is likely lost due to sudden halt. Re-homing is highly recommended.
4Probe failProbe fail. Probe is not in the expected initial state before starting probe cycle when G38.2 and G38.3 is not triggered and G38.4 and G38.5 is triggered.
5Probe failProbe fail. Probe did not contact the workpiece within the programmed travel for G38.2 and G38.4.
6Homing failHoming fail. The active homing cycle was reset.
7Homing failHoming fail. Safety door was opened during homing cycle.
8Homing failHoming fail. Pull off travel failed to clear limit switch. Try increasing pull-off setting or check wiring. Electronic limits 2.5mm Electromechanic switches 4mm e.g. $27=4
9Homing failHoming fail. Could not find limit switch within search distances. Try increasing max travel, decreasing pull-off distance, or check wiring.

Error Codes

These are the run time errors you get when the Gcode has an error, for example: G X0 Y0 (G is missing a number like G0)

Error CodeError MessageError Description
1Expected command letterG-code words consist of a letter and a value. Letter was not found.
2Bad number formatMissing the expected G-code word value or numeric value format is not valid.
3Invalid statementGrbl ‘$’ system command was not recognized or supported.
4Value < 0Negative value received for an expected positive value.
5Setting disabledHoming cycle failure. Homing is not enabled via settings.
6Value < 3 usecMinimum step pulse time must be greater than 3usec.
7EEPROM read fail. Using defaultsAn EEPROM read failed. Auto-restoring affected EEPROM to default values.
8Not idleGrbl ‘$’ command cannot be used unless Grbl is IDLE. Ensures smooth operation during a job.
9G-code lockG-code commands are locked out during alarm or jog state.
10Homing not enabledSoft limits cannot be enabled without homing also enabled.
11Line overflowMax characters per line exceeded. Received command line was not executed.
12Step rate > 30kHzGrbl ‘$’ setting value cause the step rate to exceed the maximum supported.
13Check DoorSafety door detected as opened and door state initiated.
14Line length exceededBuild info or startup line exceeded EEPROM line length limit. Line not stored.
15Travel exceededJog target exceeds machine travel. Jog command has been ignored.
16Invalid jog commandJog command has no ‘=’ or contains prohibited g-code.
17Setting disabledLaser mode requires PWM output.
20Unsupported commandUnsupported or invalid g-code command found in block.
21Modal group violationMore than one g-code command from same modal group found in block.
22Undefined feed rateFeed rate has not yet been set or is undefined.
23Invalid gcode ID:23G-code command in block requires an integer value.
24Invalid gcode ID:24More than one g-code command that requires axis words found in block.
25Invalid gcode ID:25Repeated g-code word found in block.
26Invalid gcode ID:26No axis words found in block for g-code command or current modal state which requires them.
27Invalid gcode ID:27Line number value is invalid.
28Invalid gcode ID:28G-code command is missing a required value word.
29Invalid gcode ID:29G59.x work coordinate systems are not supported.
30Invalid gcode ID:30G53 only allowed with G0 and G1 motion modes.
31Invalid gcode ID:31Axis words found in block when no command or current modal state uses them.
32Invalid gcode ID:32G2 and G3 arcs require at least one in-plane axis word.
33Invalid gcode ID:33Motion command target is invalid.
34Invalid gcode ID:34Arc radius value is invalid.
35Invalid gcode ID:35G2 and G3 arcs require at least one in-plane offset word.
36Invalid gcode ID:36Unused value words found in block.
37Invalid gcode ID:37G43.1 dynamic tool length offset is not assigned to configured tool length axis.
38Invalid gcode ID:38Tool number greater than max supported value.

Option Codes

These codes you can use via the command line like for example: restore the eeprom factory settings -> you issue a ‘$*’ command

OPT: Code Build-Option DescriptionState
VVariable spindleEnabled
NLine numbersEnabled
MMist coolant M7Enabled
PParking motionEnabled
ZHoming force originEnabled
HHoming single axis commandsEnabled
TTwo limit switches on axisEnabled
AAllow feed rate overrides in probe cyclesEnabled
DUse spindle direction as enable pinEnabled
0Spindle enable off when speed is zeroEnabled
SSoftware limit pin debouncingEnabled
RParking override controlEnabled
*Restore all EEPROM commandDisabled
$Restore EEPROM `$` settings commandDisabled
#Restore EEPROM parameter data commandDisabled
IBuild info write user string commandDisabled
EForce sync upon EEPROM writeDisabled
WForce sync upon work coordinate offset changeDisabled
LHoming initialization auto-lockDisabled