I found a couple topics about using E0 and E1 as X2 and Y2.
So instead of wiring the two X steppers and two Y steppers in series or parallel, you would use 5 stepper drivers (4, plus 1 for Z-axis), each using one port on ramps. I know you don’t want to support these config, but I have a rather small MPCNC, meaning I don’t have to cut the stepper wires to extend them. I don’t think it makes sense to cut the wires/plugs just to wire it in series or parallel, when the ramps comes with 5 drivers already, so the option for going for 5 drivers is basicly already there.
I extracted User “O-Toms” patch (https://www.v1engineering.com/forum/topic/marlinramps-patch-to-use-extruder-drivers-as-additionnal-xy-drivers/) and implemented his changes in my MPCNC-marlin firmware.
[quote]
Configuration_adv.h, un-comment these two lines:
#define X_DUAL_STEPPER_DRIVERS
#define Y_DUAL_STEPPER_DRIVERS[/quote]
[quote]
pins_RAMPS.h, add these lines:
#define X2_STEP_PIN E0_STEP_PIN // (actually this is set to 26)
#define X2_DIR_PIN E0_DIR_PIN // (28)
#define X2_ENABLE_PIN E0_ENABLE_PIN // (24)
#define Y2_STEP_PIN E1_STEP_PIN
#define Y2_DIR_PIN E1_DIR_PIN
#define Y2_ENABLE_PIN E1_ENABLE_PIN[/quote]
For the Y-axis this works straight away, but the stepper connected to E0 (the second X-stepper) does only turn in one direction. If you let turn it forwards or backwards, this stepper always turns in the same direction.
If you google for “motor only turning in one direction” (or something like that), it looks like its an endstop issue. I don’t have, or use, endstops, neither I know if endstops are actually configured in the vanilla MPCNC-marlin firmware (I’m using “MPCNC813_GLCD_T8”).
Any advice for this? Is there any other flag in marlin that is configuring E0 as a “only go in one direction, no matter what comes”-motor? Or is it really something endstop related? Or are the pins (26, 28, 24) wrong? (tried some others I googled for - those just make the E0 motor stop working at all)
edit:
I also tried this setting posted by User “AntTuru” (https://www.v1engineering.com/forum/topic/marlin-using-e-drivers-to-run-2nd-x-and-y-motors/#post-30610), looks like he is re-using 4, 2, 15 und 19. When I use these pins, the motor won’t do anything.