AX58100

Thanks for the information.
How do you set the lcec.0.D1.stepspermm1 command to control the stepper motor driver, for example, if it is set to 1600?
What relationship should it have with respect to the screw pitch if it has a pitch of 5 mm per turn?

Just to divide 1600 by 5 = 320 steps/mm.

Do you have the steppers running? I am curious if that voltage level shifter works. I mean, it should work but I never came that far in my build.

I have not been able to test it yet, but with a multimeter I have verified that when I change the direction of a motor the DIR pin changes from 0 to 5 volts.

Then it seems to work. Good luck with the steppers.

I still don't understand, what do I use the lcec.0.D1.stepspermm pins for?

The thing that updates every millisecond is CommandedPosition, linuxcnc calculates a new position value every millisecond which goes to the MCU on the card. How many steps does the step generator need to make to go to that new position?
There is the scaling parameter 320 steps/mm. Say it needs to go 0.1 mm in one millisecond which is awfully fast but just an example. 0.1 *320 = 32 steps to make during that millisecond.
Another way could be to calculate number of steps to move in hal, in linuxcnc. It is not done that way. The new position, commanded positition, in machine units, is fed to the stepper driver, be it Ethercat, parallel port or Mesa card.
If you change the microstep setting on the driver itself you need to change stepspermm accordingly.