{"id":"mcode-m63","model_id":"M63","name":"LinuxCNC M63 Digital Output Off, Synchronized","summary":"M63 turns a digital output off, with the change queued to occur in step with machine motion. The P word selects the output number, which ranges from 0 to a default maximum of 3. The queued change is applied at the start of the next motion command, so a motion G-code should follow the M63.","study_notes":["M63 belongs to the M62-M65 digital output control group; M62 turns an output on synchronized with motion, and M64/M65 turn an output on/off immediately.","The P word specifies the digital output number and ranges from 0 to a default value of 3; the count can be increased with the num_dio parameter when loading the motion controller.","M62 and M63 commands are queued; a later command referring to the same output number overwrites the earlier setting, and multiple output changes can be programmed with more than one M62/M63 line.","The output change occurs at the beginning of the next motion command; if no motion command follows, the queued change does not happen, so a motion G-code (G0, G1, etc.) should be programmed right after M62/M63.","M63 will not function unless the corresponding motion.digital-out-nn HAL pins are connected to outputs in the HAL file.","M64 and M65 take effect immediately as received by the motion controller, are not synchronized with movement, and will break blending."],"safety_notes":[],"sources":[{"url":"https://linuxcnc.org/docs/html/gcode/m-code.html#mcode:m62-m65","title":"M-Codes","accessed":"2026-10-26"}],"verification":{"status":"source_checked","checked_at":"2026-10-26","values":5,"method":"llm_source_check"},"updated_at":"2026-10-26","type":"instruction","spec":{"language":"gcode","code":"M63","group":"digital output control","syntax":"M63 P-","parameters":[{"name":"P-","description":"Digital output number, ranging from 0 to a default value of 3; adjustable using the num_dio parameter when loading the motion controller."}],"dialect":"LinuxCNC","related":[],"standards":[]},"url":"https://machineschema.com/instruction/mcode-m63","license":"https://creativecommons.org/licenses/by/4.0/"}