Hello, old-schoolers of my age, who grew up in 1980-1990s.
Today I bought a very cheap chinese wristwatch with 4 buttons, which still can be controlled as these old watches of 1980s:
How nostalgic is this -- despite the fact that manual is in chinese (I don't know a word), I knew how to set it up by heart, because this method is still unchanged.
In fact, these diagrams are FAs or FSMs, despite the fact this is a manual for laymen.
Also, you may recall old VCR recorders of that epoch, that were controlled with similar excruciating button sequences. Do you still remember how to program your VCR to start recording at a specific time and record your favorite TV show?
I would be bold enough to state that wristwatches and VCRs of 1980s and 1990s are the most popular and recognizable FAs/FSMs, to almost all people in the world. So almost anyone saw FAs/FSMs and used them.
And of course, these wristwatches implement FA/FSM internally. There is a current state (in some register) which changes according to rules and inputs from buttons.
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