Genmitsu 3018-Pro 5.5W Laser Module User Guide - SainSmart
When using a laser in conjunction with a GRBL based CNC router such as the 3018 Pro, there is an important setting in GRBL which lets the CNC know what mode you want to be in. This setting is $32 and it can be edited in your command console by typing $32=1 to turn on Laser Mode, and can be turned off by typing $32=0.