The GRBL $# query reports stored coordinate data. In a laser workflow, the useful records are the active work-coordinate families G54–G59, the saved G28 and G30 positions, and the temporary G92 offset. The query reads controller state; it does not move the laser.
Relate reports to position
Machine position is the controller's physical reference after a valid homing or manufacturer-defined startup procedure. Work position is derived from machine position through the active work offset. A saved G54–G59 value or temporary G92 change can therefore make LightBurn's displayed work coordinates differ without any physical movement.
Use $# together with a realtime status report and the current parser state. Record MPos, WPos or WCO as shown by the controller, the selected LightBurn Start From mode, the device profile and whether homing was completed. Do not edit stored offsets merely to make one number look familiar.
Treat unexpected CNC data as a scope warning
Some GRBL builds can also return PRB probe-position or TLO tool-length records. Those belong to CNC probing and tool workflows, not to normal LaserLearn laser cutting or engraving instruction. If they appear unexpectedly, verify the source of the command or file, the active LightBurn device profile and whether the controller firmware is intended for this laser. LaserLearn recognizes the records so they are not mistaken for random text, but does not teach them as laser features.