Copy M106 command plugin

Development
1

For PrusaSlicer does not support a fan on a second extruder, I started to create a plugin that copies the M106 value to the second fan.

I started with this: Plugin-Examples/rewrite_m107.py at 48316b8a5257763966d0c6c0a2f57a4825bb1db1 · OctoPrint/Plugin-Examples · GitHub

And now I am here:

# coding=utf-8

import octoprint.plugin

class CopyM106Plugin(octoprint.plugin.OctoPrintPlugin):
	def copy_m106(self, comm_instance, phase, cmd, cmd_type, gcode, *args, **kwargs):
		if gcode and gcode == "M106":	   
			# global cmd_copy_m106
			cmd_copy_m106 = cmd
			cmd_copy_m106 = cmd_copy_m106[5:]
			self._logger.info(cmd_copy_m106)
		return [("M106 "+ cmd_copy_m106),
				("M106 P1 " + cmd_copy_m106)]

			
__plugin_name__ = "Copy M106"
__plugin_pythoncompat__ = ">=2.7,<4"
def __plugin_load__():
	global __plugin_implementation__
	__plugin_implementation__ = CopyM106Plugin()

	global __plugin_hooks__
	__plugin_hooks__ = {
		"octoprint.comm.protocol.gcode.queuing": __plugin_implementation__.copy_m106,
	}

So far it works well on the virtual printer:

2021-04-08 18:50:29,781 - Changing monitoring state from "Operational" to "Starting"
2021-04-08 18:50:30,451 - Send: N1 M106 S0*102
2021-04-08 18:50:30,473 - Recv: ok
2021-04-08 18:50:30,479 - Send: N2 M106 P1 S0*36
2021-04-08 18:50:30,489 - Recv: ok
2021-04-08 18:50:30,494 - Changing monitoring state from "Starting" to "Printing"
2021-04-08 18:50:30,580 - Send: N3 M106 S10*85
2021-04-08 18:50:30,588 - Recv: ok
2021-04-08 18:50:30,590 - Send: N4 M106 P1 S10*19
2021-04-08 18:50:30,595 - Recv: ok
2021-04-08 18:50:30,654 - Send: N5 M106 S255*96
2021-04-08 18:50:30,661 - Recv: ok
2021-04-08 18:50:30,663 - Send: N6 M106 P1 S255*34
2021-04-08 18:50:30,668 - Recv: ok
2021-04-08 18:50:30,727 - Send: N7 M106 S0*96
2021-04-08 18:50:30,734 - Recv: ok
2021-04-08 18:50:30,736 - Send: N8 M106 P1 S0*46
2021-04-08 18:50:30,741 - Recv: ok
2021-04-08 18:50:30,813 - Changing monitoring state from "Printing" to "Finishing"
2021-04-08 18:50:31,741 - Recv: wait
2021-04-08 18:50:32,741 - Recv: wait
2021-04-08 18:50:33,744 - Recv: wait
2021-04-08 18:50:34,746 - Recv: wait
2021-04-08 18:50:35,746 - Recv: wait
2021-04-08 18:50:35,840 - Changing monitoring state from "Finishing" to "Operational"

But in octoprint.log I get the annoying UnboundLocalError:

2021-04-08 18:48:50,855 - octoprint.util.comm - ERROR - Error while processing hook M106_Copy for phase queuing and command M110 N0:
Traceback (most recent call last):
  File "/home/pi/oprint/lib/python3.7/site-packages/octoprint/util/comm.py", line 4509, in _process_command_phase
    tags=tags,
  File "/home/pi/oprint/lib/python3.7/site-packages/octoprint/util/__init__.py", line 1941, in wrapper
    return f(*args, **kwargs)
  File "/home/pi/.octoprint/plugins/M106_Copy.py", line 12, in copy_m106
    return [("M106 "+ cmd_copy_m106),
UnboundLocalError: local variable 'cmd_copy_m106' referenced before assignment
2021-04-08 18:48:51,018 - octoprint.filemanager.analysis - INFO - Starting analysis of local:Test.gcode
2021-04-08 18:48:51,022 - octoprint.filemanager.analysis - INFO - Invoking analysis command: /home/pi/oprint/bin/python -m octoprint analysis gcode --speed-x=6000 --speed-y=6000 --max-t=10 --throttle=0.01 --throttle-lines=100 --bed-z=0.0 --offset 0.0 0.0 /home/pi/.octoprint/uploads/Test.gcode
2021-04-08 18:48:51,224 - octoprint.util.comm - ERROR - Error while processing hook M106_Copy for phase queuing and command M110 N0:
Traceback (most recent call last):
  File "/home/pi/oprint/lib/python3.7/site-packages/octoprint/util/comm.py", line 4509, in _process_command_phase
    tags=tags,
  File "/home/pi/oprint/lib/python3.7/site-packages/octoprint/util/__init__.py", line 1941, in wrapper
    return f(*args, **kwargs)
  File "/home/pi/.octoprint/plugins/M106_Copy.py", line 12, in copy_m106
    return [("M106 "+ cmd_copy_m106),
UnboundLocalError: local variable 'cmd_copy_m106' referenced before assignment
...

I set the variable cmd_copy_m106 to global, but that resulted in keeping the variable to the first truncated value (S0)

Any ideas?

2

Your return statement has the variable referenced and it's only defined if gcode and gcode == "M106"

Indent the return to be in line with the conditional then put a new return None in its former place

https://docs.octoprint.org/en/master/plugins/hooks.html#octoprint-comm-protocol-gcode-phase

Might also have to adjust the format for what is returned when M106

3

Yesss! This works fine!

I think I will dive deeper into plugin development.

Thanks a lot @kantlivelong !

So here is the plugin:

# coding=utf-8

import octoprint.plugin

class CopyM106Plugin(octoprint.plugin.OctoPrintPlugin):
	def copy_m106(self, comm_instance, phase, cmd, cmd_type, gcode, *args, **kwargs):
		if gcode and gcode == "M106":	   
			cmd_copy_m106 = cmd
			cmd_copy_m106 = cmd_copy_m106[5:]
			self._logger.info(cmd_copy_m106)
			return [("M106 "+ cmd_copy_m106),
					("M106 P1 " + cmd_copy_m106)]
		return None			

			
__plugin_name__ = "Copy M106"
__plugin_pythoncompat__ = ">=2.7,<4"
def __plugin_load__():
	global __plugin_implementation__
	__plugin_implementation__ = CopyM106Plugin()

	global __plugin_hooks__
	__plugin_hooks__ = {
		"octoprint.comm.protocol.gcode.queuing": __plugin_implementation__.copy_m106,
	}
4

:thumbsup:

5

This looks exactly like what I need to control my second parts cooling fan connected on a different port than P0!
How do I use this script?

6

Just install the file inside this zip:

M106_Copy.zip (536 Bytes)

With:

grafik
grafik559×836 36.7 KB