Microprogrammed mechanism is a technique to implement the control logic necessary to execute instructions within a processor. It is based on the general idea of fetching low-level microinstructions from a control store and deriving the appropriate control signals to be active for a single clock cycle, as well as microprogram sequencing information, from each microinstruction. Although hybrid techniques exist, microprogramming is generally contrasted with hardwired implementation techniques.
Although loose usage has sometimes used the term”microprogramming” with the idea of “programming a microcomputer”, this is not the standard definition. Rather, microprogramming is a systematic technique for implementing the control logic of a computer’s central processing unit. It is a form of stored-program logic that substitutes for hardwired control circuitry.