I recently asked the same type of question here about limits and the G540. I was advised to connect all the limits together and wire them normally open and route them to 1 input on the G540, that way you only use 1 input. I did this and it has worked well for me. I also connected all of my home switches together and wired them to 1 input, this also worked well. The only exception to this is that I am going to add 1 more home switch to my table for my X axis so that I can square my gantry (I have 2 X axis motors) the new home sensor will have to have its own home sensor and input to the G540. If you search my post (about 2 weeks old) about this you will find allot of great information about homes and limits.