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Why did you discard microprogramming?

I designed the machine around SSI/MSI integrated circuits, no LSI, so ROM chips got automatically discarded. With no ROM for storing microcode, the microprogramming approach gets some how dissimulated.

There is a philosophical argument too: According to the Heritage/1 culture, Software is something "external" to the computer, something that has to be loaded at a later time and not while the computer is still waking up. Microcode is not strictly "software" but it is "soft", some kind of ghost doing its magic inside the CPU. I wanted logic functions to be done with logic circuits, not with "ghost logic".

I also find that hardwired logic is more clear: When I say that the Op Cod Fetch sequence takes 3 clock cycles I mean exactly that: 750 nanoseconds (assuming a 4 MHz clock frequency), not 3 microinstruction cycles each of which takes in turn some other nanoseconds to complete.