I need to find enough spare pins to add two extra motor drivers for my big printer build. I am using two motors for the Y and three for Z, I can use the E1 for one of them because I won't be using a second extruder.

I need to find six pins to get two external drivers working. I know the MKS Gen L has 3 servo ports, but one will be going to my BLTouch. Can I reuse the other ports? What other ports can I use for adding extra motor drivers?

I know it also has AUX ports as well but I don't know if they are being using by somthing else.


1 Answer 1


Have a look at the boards pinout: MKS Gen L pinout from MKSs github

You'll need 3 pins for each additional driver - enable, step, and dir. The AUX-2 connector should give your 8 GPIO pins for that, without losing other functionality like the display.

You might also be able to wire your Y axis motors in series, saving one stepper driver. You could then use E1 and three of the four servo pins for the 2nd and 3rd Z axis stepper drivers.

  • $\begingroup$ I need the Y motors to move independently so I can have a homing switch on each side. It's a very long bed so dual Y homing is needed to prevent racking $\endgroup$ Jun 10, 2021 at 2:23
  • $\begingroup$ Alright, sounds reasonable. A belt isn't an option either, to keep them in sync? You could also look at more modern boards like the Fysetc Spider or BTT Octopus, which would have sufficient motor drivers slots for your project. $\endgroup$
    – towe
    Jun 15, 2021 at 6:36

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .