flexi-bot/docs/marlin/_gcode/M109.md

tag	title	brief	author	group	codes	notes	parameters	examples
m0109	Wait for Hotend Temperature	Wait for the hot end to reach its target.	thinkyhead	thermal	M109	With `PRINTJOB_TIMER_AUTOSTART` this command will start the print job if heating, and stop the print job timer if the temperature is set at or below half of `EXTRUDE_MINTEMP`. This command (as well as [`M190`](/docs/gcode/M190.html)) can block new commands from the host, preventing remote shutdown. However, if `EMERGENCY_PARSER` is enabled, a host can send [`M108`](/docs/gcode/M108.html) to break out of the wait loop. To set the hot end temperature and proceed without waiting, use [`M104`](/docs/gcode/M104.html).	tag since optional description values I 2.0.6 true Material preset index. Overrides `S`. type tag int index tag optional description values S true Target temperature (wait only when heating). Also `AUTOTEMP`: The min auto-temperature. tag type temp float tag optional description values R true Target temperature (wait for cooling or heating). tag type temp float tag optional description values F true Autotemp flag. Omit to disable autotemp. tag type flag bool tag optional description values B true With `AUTOTEMP`, the max auto-temperature. tag type temp float tag optional description values T true Hotend index. If omitted, the currently active hotend will be used. tag type index int	pre code Set target temperature and wait (if heating up) M109 S180 pre code Set target temperature, wait even if cooling M109 R120 pre code Set target temperature for E1 and wait (if heating up) M109 T1 R205 pre code `AUTOTEMP`: Set autotemp range, wait for temp M109 F S180 B190 pre code `AUTOTEMP`: Disable autotemp, wait for temp M109

This command optionally sets a new target hot end temperature and waits for the target temperature to be reached before proceeding. If the temperature is set with S then M109 waits only when heating. If the temperature is set with R then M109 will also wait for the temperature to go down.