setting a axis home location

Hello,
I'm using EMC/Axis v 2.3.5 on a 3 axis mill with home/limit switches.
I'm trying to define a home location inside the machine's work envelope by moving an axis until it trips a switch. When I try a home function in AXIS the motion direction is opposite to the location where home position should be and eventually the axis trips the opposite switch. Tthe step.conf configuration for that axis has home location spec'd as zero. The axis register is incrementing when it's going in a positive direction.
So instead of home being at lower left table position, it's trying to find a home location at the upper right hand corner instead. Any suggestions ?
thanks
Denis