Digital Dream UC300 User Manual page 20

Here you can configure according to your actual needs the corresponding function. Optional Function include
XYZABC 6axis's Upper and lower limit、XYZABC 6axis's HOME point. We set upper limit and home of
XYZA to 3456 corresponding IN3/IN4/IN5/IN6 of the Controller board.
Digital Dream Mach3 Motion Controller Page -18 UC300 User's Manual