I realize several people have their own tracking forks of Marlin, but they're all to add support for hardware I don't have and none are for the dual setup, so here's mine: https://github.com/jinschoi/Marlin
Fork of latest Release branch (1.0.2) with support for v4 dual extruders. Changes from stock:
Configuration set up for M2, using settings blindly transferred over one by one from MakerGear's M2_Dual_Extruder_Marlin firmware. Only settings not taken directly were to enable the auto extruder fan and put in my own PID values.
temperature.cpp modified to workaround a compiler bug with dual extruders using the least invasive "fix" from here: https://github.com/MarlinFirmware/Marlin/issues/1523
stepper.cpp modified to add a workaround for skipped steps during fast moves exacerbated in newer versions of the Arduino IDE.
I haven't given it a thorough testing yet.
Yet another Marlin for M2 fork
Re: Yet another Marlin for M2 fork
Ok this is good jin and thanks. Now to change this from a dual firmware to a single is it just a matter of turning off tool 1? any special changes need to be made for that to happen?
Re: Yet another Marlin for M2 fork
To convert it to a plain jane single extruder version, yes, set EXTRUDERS to 1, and also set EXTRUDER_1_AUTO_FAN_PIN from 6 to -1 to turn off the auto extruder fan activation on the non-existent second extruder (Configuration_adv.h).
For the E3D, you will want to do whatever you do for that as well (extruder current and PID settings, thermistor table switch).
For the E3D, you will want to do whatever you do for that as well (extruder current and PID settings, thermistor table switch).
Re: Yet another Marlin for M2 fork
Oops, missed the EEPROM support setting, turned that on just now.
Re: Yet another Marlin for M2 fork
Aaaand I got the missed steps workaround wrong, so I had to fix that.