ok, I feared that it would be like that currently.
I am thinking of a simple workaround via an external arduino(?) with stepper driver. The external motor has just to be able to home itself and drive to 9 different positions.
--> Is there a way that a gcode would trigger an external device (arduino?). I just thought of

M118: Used to send messages to a specific target: USB, PanelDue/UART, HTTP or Telnet
--> M118 P2 S"home" ;send home signal via UART to external arduino
--> M118 P2 S"0" ;send position 0 via UART to external arduino

M118 P5 would work in addition for Due 3 and second UART interface, right?

to precise my request:
Currently I am running my machine via klipper. I am moving to Duet because klipper has severe multi gantry limitations.
But I do have one issue left: My machine requires the adjustment of an external filament device during printing without stopping the print. Speaking in reprap language that would mean an additional one motor Independent axis I guess.
In klipper this is named manual stepper and looks like this:

no issue...
"one" thing I don't fully understand yet from the documentation:
"For command streams that originate from file, each motion system uses a separate GCode processor..."
--> Is my understanding correct that ...from file... means that the gcode has to be stored on SD card?

is there a special login / permission needed to see this beta documentation? Or are we talking about this one https://docs.duet3d.com/en/User_manual/RepRapFirmware/Multiple_motion_systems

I am currently studying this

@dc42 just to let you know: I am new to Duet3d but not new to mechanics and 3d printing --> I have already built a corexy multi gantry system, will purchase the latest duet 3 board with extension to 11 drivers and install the latest 3.5 beta for testing. It is definitively aimed to run in SBC mode as the printer has to download and start print jobs via firebase cloud triggered via API.
Side comment: I raised a question in the general thread regarding "is it possible to let reprap run a complete separate stepper motor in parallel to the print job". If'd get this solved in addition, my dreams coming true

oh, that is very interesting.
Is there an estimation when 3.5 will be released? Is there already a beta for testing available?

Hi,

I searched around but could not find a clear answer for my question.
I'd like to know if there is an option to manually trigger/move additional steppers during a print based on gcode commands or macros.
Two examples:

1. I would like to run a stepper motor for adjusting external parts. The motor is not involved into the printer kinematic
2. I would like to run a second extruder motor (for T1) to prime a nozzle while the print with T0 is still ongoing.

Would that be possible?
Regards,
Andy

Hello to all 3d print addicted
Already in 2019 exactly this idea came to my mind and it did not left me. Some months ago I finished the mechanics side and the dual gantry corexy is running with just one gantry.
Currently I am struggling with the strategy to get the second gantry to life.
Already in 2017 titan robotics announced the "the cronus" which has 5 independent gantries. Every gantry has its own g-code (created by autodesk netfabb 2017). Practically I do not know how they achieved the synchronisation between the gantries and how to force each gantry to park and pause when he has finished its layer and has to wait for the others.
In general I think this is a totally underestimated technologie / strategy where we should put more effort into.