if you want to see a documented CPU architecture example of what is "microcode", "macrocode", and what runs on the top of what, so to see the boundary between hardware and software, as far as a CPU is concerned, look at the "
MIC-1", a processor architecture invented by Andrew Tanenbaum to use as a simple but complete example in his teaching book "
Structured Computer Organization", the design is 100% accademic and consists of a very simple control unit that runs microcode from a 512-words store.
oh, now we have the 5th edition of the Holy Book
![Shocked :o](https://www.eevblog.com/forum/Smileys/default/xshocked.gif.pagespeed.ic.CrwtrNUjLO.png)