Dual printhead that can print at the same time?

Hi guys, sorry to bring up this dual printhead problem again. Currently I have a prusa i3 printer and I am suppose to use extruder 1 and 2 at the same time to mix the content together while printing. I am wondering is it allowed in marlin firmware? I have changed the setting to #define MOTHERBOARD 34 and defined 2 printhead in configuration.h. Any more modifications I should do to the firmware?I am considering using a Y shape nozzle so I don't need to do printhead offset.
I read that marlin do not support mixing ratio M code How should I modify the G code accordingly?
Thanks ahead.

You have a slicer that has a color mixing option and generates the gcode accordingly? Can you attach an example? What sort of .stl file do you need?

Then you'd write an addition in marlin_main code, that filters out this M code and translates it to E0, E1 steps and send it to the planner ( like usual ).
-Olaf

Basically you wanted to have colour mixing feature, can try to start from here, [richrap.blogspot.my] a project back in 2012

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o_lampe
You have a slicer that has a color mixing option and generates the gcode accordingly? Can you attach an example? What sort of .stl file do you need?

Then you'd write an addition in marlin_main code, that filters out this M code and translates it to E0, E1 steps and send it to the planner ( like usual ).
-Olaf

I am totally new to 3D printing.. currently using an prusa i3 with Arduino mega 2560 and have slic3r-mswin-x64-1-2-9a-stable, reptier host and printrun in my PC. Not sure which one is useful
I don't have a existing file yet, say if I want to print a simple straight line of 10mm, both extruder extruding materials onto the plate according to any ratio I want. What will be the g code modification? Is this possible to be done with gcode modification only? cause I really don't know how to add the M code in marlin...

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sarf2k4
Basically you wanted to have colour mixing feature, can try to start from here, [richrap.blogspot.my] a project back in 2012

Thank you I will take a look. Actually I only need to know the code and firmware modification part. I am not designing the printhead

Yes, because you already have them. I do remember that there were posts by richard himself modifying code or something by using 0-360' degree angle (I forgot). There's also colour mixing thread in reprap forum here, try googling "richrap colour mixing"

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sarf2k4
Yes, because you already have them. I do remember that there were posts by richard himself modifying code or something by using 0-360' degree angle (I forgot). There's also colour mixing thread in reprap forum here, try googling "richrap colour mixing"

Hi, so after some digging up, I changed the firmware to reprap v92. They mention v92 supports color mixing M code: M163: Set weight of mixed material and M164: Store weights.
But I really can't find an example of how to use them in a g code and the mixing theory (https://github.com/repetier/Repetier-Firmware/blob/work092/doc/Mixing%20extruder%20theory.txt) really confuses me...