Welcome to the state machine introduction lecture and this lecture I'm going to produce how state machines
operate.
Let's just start with the state machine definition a state machine is a device that can be in one of
a set number of stable conditions depending upon its previous condition and on the present values of
its inputs and what that means is we have different states we can go around it.
So we have predefined conditions or states that we specify.
And based upon inputs and also the predefined state that we're currently in we can navigate to different
states and there are two different common types of state machines.
There's Meely machine and a more machine a milling machine is a finite state machine whose output depends
on the present state as well as the present input.
So that means is if you're in say state a certain state you depending upon what state you're in and
the input is going to dictate what is the next state that you'll go to.
And generally these have fewer states than a more machine and the outputs change at clock edges and
a lot of times I'm most commonly used Milia machines.
And in this course we'll be only dealing with milling machines but there are also these also react faster
to inputs.
So machine input happens right away and then on the clock edge we transition from a state.
The next one will look at is the more machine a more machine is a state machine whose output depends
only on the present state.
So the input doesn't matter.
There's a specific input and once that it sees that input it goes depending upon the state it's in it
goes to the next state.
So generally with a more machine you have more states and a milling machine.
So you can't say OK if I get the signal if it's a when I go here for the zero I go there it's like no
once the signal is zero I go directly to that next state.
There's not no decision making the input change can cause cause change in an output change as soon as
the logic is done.
So we don't wait on the clock edge as soon as we see that input output we change state.
It happens right away.
In the more machines more logic is needed to decode the outputs since it has more circuit delays.
Now you're familiar with state machines.
Let's take a look at how to start designing one.