To communicate with a separate chip - say, an extra processor like for sound, or to connect traces/wires between extra FPGA pins and unused cartridge pins, maybe for EXP pins to go through an NES-FC cart converter for extra sound from a Famicom, or to (theoretically) communicate with some EXP port utility, how would you add more pins in the FPGA to be available to use for the PowerPak? I tried to use Xilinx's PACE, but it won't let me edit or add usable pins. It's probably something that shouldn't be too hard and can be found out by reading Xilinx's documentations and help files, but they seem to be a bit too confusing for me.