Hi, I see no comments since 4 years, but I tried to contact for using 1 port for a new interface we're developing to emulate keyboard but require an IN/OUT port for the mode "redefine keys" so one 0xXX3B port would be a nice option. We have done initial tests using 0xF73B but maybe this ZXI standard was developed with other ports in mind for keyboard interfaces of something similar to this. Using 0xxFE or even port is not an option as the redefine keys option can be manage trough standard speccy keyboard.
Thanks in advance
Mad3001