The question is do you want a tricolor version or
the tricolor version? The reprap pro use a sanguino to start with another sanguino added. But your question is of particular interest to me as I am working on a 7 color machine. On RAMPS, you have ready spaces for only enough inputs to watch to thermistors for extruders, and one for a heated bed. I think the megatronics board might have the extra extruder channel, but you are replacing your electronics. On the ramps board, on the end where the LCD shield goes, are a number of spare pins, farther from the sd port. So if you look at the source for your firmware, you may (should) be able to assign those pins for the 3 leads you need for the extruder motor, and the four that you need for the hot end. Besides for assigning the pins, you need to somehow set up your next extruder as a logical (physical?) extruder in the sli3er software. I've yet to look at the firmware source, but I'd say read thru all of it to find out how extruders are set up and identified. I will post code segments when I get this far.
Edited 1 time(s). Last edit at 05/25/2013 09:01PM by Maxx Mayhem.