I am using a 16f877 to control some relays via pushbuttons for my pool equipment. The pushbuttons have LEDs that work when the relays are on. It works well but I would like to
add another location with pushbuttons approx 100 foot away. Can I connect 2 (or 3) 16f877s
with a serial connection or I2C to accomplish this? Or should I try using a port extender?
Any help would be appreciated.

Thanks in Advance