Originally Posted by luncheon
Besides that, it would be interesting to know how many space is left on the FPGA to implement additional expansion hardware.
Using more features would mean having more IOs. Zeus68k uses _all_ of them, there is not a single pin unused. Within these boundaries, you can do whatever you like. Whatever control you would like to have... you have an FPGA between the board, the processor and the RAM. That's why there are so many features already in it.