emc help with home

Finally got emc up and running thanks to ray henrys bdi install.now I
dont know how to home an axis. If I hit the home, the axis twitches
and the display goes to 0, in essence working like a zeroing button.
I understood that the axis is supposed to slowly home toward the
limit switch and then back up a little. the home switches are mounted
and the i/o checks out fine

the system is a metric sherline with steppers. all other aspects
work except the home feature. any help is appreciated
Bill H