>> 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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