Ditto printing!

The official subforum for discussion of the installation and use of the official M2 Dual Extruder upgrade.
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Tim
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Re: Ditto printing!

Post by Tim » Sun Feb 07, 2016 4:59 pm

Slipshine wrote:You said that you modded it so it was software selectable. Is that tied in to m code to select to output to both extruders ?
Yes, but in Smoothieware, not Marlin.

I looked up relevant codes on the RepRap web page and decided that M605 was more or less compatible, although the way it's described, I think they had in mind dual independent X axis motors. But I wrote it such that "M605 S2" causes the extruders to simultaneously execute the same motor motion commands, and "M605 S0" returns it to normal.

More specifically/technically, Smoothieware is written in an object-oriented way such that each tool is an object and registers callback functions from the main loop, so in fact all extruders get their callback functions run whenever there is an extrude or retract function in the g-code, and one extruder is set "active" and runs the command, and the other is set "inactive" and stays idle. So the implementation is pretty trivial in Smoothieware, as all you have to do is prevent the extruders from being set to "inactive", then set them all to "active". I haven't looked at the Marlin implementation, so I don't know if it's as easy to implement.

Slipshine
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Re: Ditto printing!

Post by Slipshine » Tue Feb 09, 2016 12:39 am

That makes perfect sense. Are you using the makegear 24v power supply? Are there any power issues that are marginal with the extra extruder running at the same time.

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Tim
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Re: Ditto printing!

Post by Tim » Tue Feb 09, 2016 2:32 am

Slipshine wrote:That makes perfect sense. Are you using the makegear 24v power supply? Are there any power issues that are marginal with the extra extruder running at the same time.
Yes, I have the 24V power supply. The Smoothie board outputs are all comfortably rated for the motors with plenty of margin. At one point, I suggested that if I couldn't get the firmware to work, I could just use a Y-split cable on the motors in parallel (apparently in serial works, too). Haven't tried that solution, though.

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