I know there are several threads about this, but I am still not sure the best way I should proceed. I want to add rotary axis to my arduino uno setup using grbl. From my understanding, grbl will not handle this with the uno, unless you swap the wiring from an axis (usually y?) and connect your rotary stepper device to this driver. Is this correct? If I am correct on this, I am thinking about connecting it this way to make the switch from y axis to the rotary axis as easy as possible. If I connect the rotary axis to a seperate stepper driver than my current y axis (2 drivers for two seperate motors running parallel) Both axis would be connected to the same step/dir pins on the uno, but I would place two switches between the power to the drivers. If I want to use the Y axis as normal, I have the power cut off to the rotary axis driver. If I want to use the rotary axis I turn the power on to the rotary axis and power off the two drivers that run the y axis motors. Does this sound like the best/easiest way to do what I am attempting? This would also prevent me from having to change the current settings if I were to share stepper drivers between the rotary axis stepper motor and the y axis motor. Thanks!
Or a DPDT switch on DIR/STEP? Keeping the X/Y Driver powered up and enabled helps lock that axis in place for you. Without signals it will stay in place
That makes sense..... Didn't think about that. If I use the DPDT switch, wouldn't I need to use the same driver for both the rotary and the y axis?
No, seperate drivers. Switching STEP and DIR control signals between the UNO and drivers: Code: ┌───────────────┐ ┌──────────────────┐ ┌─────────────────┐ │ │ │ │ DIR │ │ │ │ │ ┌────────────────┼─────────────► │ │ │ │ │ │ STEP │ A DRIVER │ │ │ │ │ ┌──────────────┼─────────────► │ │ │ DIR │ │ │ │ │ │ │ ├────────► │ │ ───────┐ │ │ │ │ UNO │ │ │ │ │ └─────────────────┘ │ │ │ │ │ │ │ │ STEP │ │ │ │ ┌─────────────────┐ │ ├────────► │ ─────┐ │ │ DIR │ │ │ │ │ │ └────┼─────────────► │ │ │ │ │ │ STEP │ Y DRIVER │ │ │ │ └──────┼─────────────► │ │ │ │ SWITCH │ │ │ │ │ │ │ │ │ └───────────────┘ └──────────────────┘ └─────────────────┘ Made with https://asciiflow.com/ Wouldn't want to switch Motor wiring - collapsing magnetic fields create a tonne of back EMF that easily fries drivers if accidentally switched while powered on
I plan to do this with my CO2 laser as well. Originally I thought a 4DPDT switch with a locking mechanism on the gantry, but if I am understanding you correctly a 2DPDT for Sig and Dir would work and then run power in parallel to both drivers removing the need for a manual lock on the gantry? If so, you just saved me $5 plus shipping on a 4DPT switch.
