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  •  Please note: The Gnome II introduce 12 new instructions and the ability to detect pressed Buttons (can also be seen as an example of good and bad synchronization) - Find the Gnome II here

All digital electronic equipment of our modern world based at the "old" principle of the Finite State Machine. All action inside controlled by a single Clock single. (A Finite State Machine also called a Synchronous State Machine)

  •  The basic SSM consist of three blocks of logic:

    • The State Memory made by one or more D-F/F's (Yes other F/F's types possible)

    • The Next State Logic produces the Next State value (a combination of 0/1 values) which should become the new Current State by the Next Clock pulse.

    • The Output Logic will use the Current State the produce an Output combination (Moore Output)
      If the Output depends on both input values and the Current State are they name Mealy Outputs.

    • A more simple way to produce output will be a technique called "Output Coded States".





The "Brain" of a CPU actually a State Machine which works in a number of states (three in this case) in order to Fetch, Decode and Execute instructions stored in the Program Memory.