## Meanings of Grbl messages and error/alarm codes #### _'error:' Codes_ Format - `(v1.0)` `:` `(v0.9)` - `Description` - `error:1` : `error: Expected command letter` - G-code words consist of a letter and a value. Letter was not found. - `error:2` : `error: Bad number format` - Numeric value format is not valid or missing an expected value. - `error:3` : `error: Invalid statement` - Grbl '$' system command was not recognized or supported - `error:4` : `error: Value < 0` - Negative value received for an expected positive value. - `error:5` : `error: Setting disabled` - Homing cycle is not enabled via settings. - `error:6` : `error: Value < 3 usec` - Minimum step pulse time must be greater than 3usec - `error:7` : `error: EEPROM read fail. Using defaults` - EEPROM read failed. Reset and restored to default values. - `error:8` : `error: Not idle` - Grbl '$' command cannot be used unless Grbl is IDLE. Ensures smooth operation during a job. - `error:9` : `error: G-code lock` - G-code locked out during alarm or jog state - `error:10` : `error: Homing not enabled` - Soft limits cannot be enabled without homing also enabled. - `error:11` : `error: Line overflow` - Max characters per line exceeded. Line was not processed and executed. - `error:12` : `error: Step rate > 30kHz`* - Grbl '$' setting value exceeds the maximum step rate supported. - `error:13` : `error: Check Door` - Safety door detected as opened and door state initiated. - `error:14` : `error: Line length exceeded` - (Grbl-Mega Only) Build info or startup line exceeded EEPROM line length limit. - `error:15` : `error: Travel exceeded` - Jog target exceeds machine travel. Command ignored. - `error:16` : `error: Invalid jog command` - Jog command with no '=' or contains prohibited g-code. - `error:20` : `error: Unsupported command` - Unsupported or invalid g-code command found in block. - `error:21` : `error: Modal group violation` - More than one g-code command from same modal group found in block. - `error:22` : `error: Undefined feed rate` - Feed rate has not yet been set or is undefined. - `error:23` : `error: Invalid gcode ID:23` - G-code command in block requires an integer value. - `error:24` : `error: Invalid gcode ID:24` - More than one g-code command that requires axis words found in block. - `error:25` : `error: Invalid gcode ID:25` - Repeated g-code word found in block. - `error:26` : `error: Invalid gcode ID:26` - No axis words found in block for g-code command or mode which requires them. - `error:27` : `error: Invalid gcode ID:27` - Line number value is invalid - `error:28` : `error: Invalid gcode ID:28` - G-code command is missing a required value word. - `error:29` : `error: Invalid gcode ID:29` - Work coordinate system commanded not supported. - `error:30` : `error: Invalid gcode ID:30` - G53 only allowed during G0 and G1 motion modes. - `error:31` : `error: Invalid gcode ID:31` - Axis words found in block while no command uses them. - `error:32` : `error: Invalid gcode ID:32` - G2/3 arcs require at least one in-plane axis word. - `error:33` : `error: Invalid gcode ID:33` - Motion command target is invalid. - `error:34` : `error: Invalid gcode ID:34` - Arc radius value is invalid. - `error:35` : `error: Invalid gcode ID:35` - G2/3 arcs require at least one in-plane offset word. - `error:36` : `error: Invalid gcode ID:36` - Unused value words found in block. - `error:37` : `error: Invalid gcode ID:37` - G43.1 dynamic tool length offset assigned to wrong axis. `*` indicates feedback enabled only by compile-time option. ----- #### 'Alarm:' Codes Format - `(v1.0)` `:` `(v0.9)` - `Description` - `ALARM:1` : `ALARM: Hard limit` - Hard limit has been triggered. Machine position is likely lost due to sudden stop. Re-homing is highly recommended. ` - `ALARM:2` : `ALARM: Soft limit` - G-code motion target exceeds machine travel. Machine position safely retained. Alarm may be unlocked. - `ALARM:3` : `ALARM: Abort during cycle` - Reset while in motion. Grbl cannot guarantee position. Lost steps are likely. Re-homing is highly recommended. - `ALARM:4` : `ALARM: Probe fail` - If probe is not in the expected initial state before starting probe cycle, where G38.2 and G38.3 is not triggered and G38.4 and G38.5 is triggered. - `ALARM:5` : `ALARM: Probe fail` - If the probe fails to contact the workpiece within the programmed travel for G38.2 and G38.4. - `ALARM:6` : `ALARM: Homing fail` - If the active homing cycle was reset. - `ALARM:7` : `ALARM: Homing fail` - If the safety door was opened during homing cycle. - `ALARM:8` : `ALARM: Homing fail` - Pull off travel failed to clear limit switch. Try increasing pull-off setting or check wiring. - `ALARM:9` : `ALARM: Homing fail` - Failed to find limit switch within travel. Defined as `1.5 * max_travel` on search and `5 * pulloff` on locate phases. ----- #### Message Descriptions Format - `Message` - `Description` - `[Reset to continue]` - Critical event message. Reset is required before Grbl accepts any other commands. This prevents ongoing command streaming and risking a motion before the alarm is acknowledged. Hard or soft limit errors will trigger this event. - `[‘$H’|’$X’ to unlock]`- Alarm message at initialization. All g-code commands and some ‘$’ are blocked until unlocked via homing or $X. - `[Caution: Unlocked]` - Alarm unlock $X acknowledgement. - `[Enabled]` - Indicates Grbl’s check-mode is enabled. - `[Disabled]` - Indicates Grbl’s check-mode is disabled. Grbl is automatically reset afterwards. - `[Check Door]` - Safety door detected as open. This message appears either immediately upon a safety door ajar or if the safety is open when Grbl initializes after a power-up/reset. - `[Check Limits]` - If Grbl detects a limit switch is triggered after power-up/reset and hard limits are enabled, this will appear as a courtesy message. - `[Pgm End]` - M2/30 program end message to denote g-code modes have been restored to defaults according to the M2/30 g-code description. - `[Restoring defaults]` - Acknowledgement message when restoring EEPROM defaults via a `$RST=` command.