Just began studying automata. I've already seen several examples of the applications of finite automata: pattern matching, automatic doors, etc. And so far, I understand the logical connection between those mechanisms and state diagrams and formal definitions. But I'm curious, what thing is implementing time steps—if that's what they're called—allowing states to transition. I know a tiny bit about computer architecture so I'm thinking it's like a processor clock, you know, something just ticking on and off very rapidly. Then the automata takes input on every "tick" of said clock. But with different devices using different current types (AC/DC) how is this actually being accomplished in an arbitrary physical device?
Now that I'm writing this out, it seems clear there are multiple ways to accomplish that ticking depending on what we're talking about, but I'm just looking for the most common examples found in real-life. For example what is allowing the sequence of input signals to occur in an automatic door?