How to configure home all including probe

Dear friends, I have a 3axis cnc (home made), the emc2 2.4 and I have four limit switches. The first is at the X begining (left), the second at the Y begining (back) , the third at the upper position of Z axis and the last at the bottom position near the table. I have configured that the homeall button moves the router at the left, back and up. Now I want to include an additional movement. To low the router to press the fourth switch. I beg my friends to help me because I am very new to emc2 and I don't know what to do. Please the instructions must be step by step because I don't know many things about emc2.

Thank you

Hello,

Is the fourth switch to set tool height?
Have you looked here?
softsolder.com/2010/04/14/emc2-ugliest-t...-probe-station-ever/

Rick G