Limits

I've got The machine all done and all the electronics hooked up except
for the limit and home switches, I have both limit switches on each axis
hooked together so either one will trigger a response. Altogether I have
3 limit wires and 3 home wires with one common.I have a DV1 V1.2
parallel port interface but it only has provision for 5 input switches.
Does anyone know of a solution to this problem?