Z80 port map

Some infos from User:kyuusaku

The decode mask for reading ports is always $0C. The one for writes is indicated for each case.

Note that the Z80 ROM bank selection is done by reading ports.

SNK used an obscure feature of the Z80: when accessing ports, the entire address bus is set, not only the lower 8 bits.

The banks can then be chosen by putting the bank number in B, the port number in C and doing IN A,(C). This is handled by in cartridges.