@lopta @agonzalez If you mean my Z80 thing ? No it's just "a bus I invented" more or less "as the signals were coming out". It has some "extra stuff" as that among things that CPLD does a bit of "Memory mapping" adding 5 more extra AD lines plus has a concept on "On board mem/IO" and "Off board mem/IO" to allow me to address extra memory/IO well over the 64K limit. In fact there are 256K or ram in that board and I can map it in segments.