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>> Well, a "ROM" can be just a grid of wires, some connected and some not.
>
> Yes? I was saying something with a program counter that runs mulitple
> instructions per CPU instruction would count as microcode, regardless of
> how you stored the code it's running.
So if it doesn't use a counter it's not microcode?
As you say, we're just arguing about semantics now. I always thought of
microcode as being a block of ROM (or even some kind of EPROM) which
actual address decode circuitry, so that you can execute jumps and so
forth. By contrast, the CPU I'm designing has no such thing. It's just
that on each clock pulse, a different control line becomes active, and
that line connects to one or more control lines (possibly via logic
gates that pass the signal only if the opcode has certain bits set). I
wouldn't call that microcode; it'd call that "a custom arrangement of
gates".
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