Said Jon:
" In a microcoded machine, the same hardware is used for every
microinstruction. In random logic, custom designed circuitry is used for
each special case."
Best way to get a handle on the distinction is to read up on the originator
of the concept, Maurice Wilkes:
https://en.wikipedia.org/wiki/Maurice_Wilkes
https://amturing.acm.org/info/wilkes_1001395.cfm
The original paper:
http://www.cs.princeton.edu/courses/archive/fall09/cos375/BestWay.pdf
"The Best Way to Design an Automatic Calculating Machine" (1951)
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