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We know that the memory cells in a sequential circuit saved the circuit.

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States, however, what are the states in a sequential circuit?

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This lecture concisely answers this question.

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More detail and usage of states will be explained along the course.

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As we noticed in previous lectures, in contrast to the combination of circuits, the behavior of the

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control circuits depends not only on the current inputs, but also on the past inputs and outputs.

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Flipflops serves to keep track of these past inputs and outputs at each time.

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The value is stored in flipflops.

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At each time it's called the state of the sequential circuit.

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In other words, states encapsulate the past inputs and outputs up to the specific time.

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Therefore, the transitions between states can describe the behavior of the sequential circuit.

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Later in this course, I will explain how to use the state transition model through a finite state machine

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or FSM for short to design a wide range of sequential circuits.

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In this lecture, I'm only focusing on basic ideas.

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Let's consider a single flip flop, its output can have two states corresponding to zero and one logic

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values are used as zero and as one to name these states.

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The flip flop changes its state and the rising edge of the clock if the proper value appears on the

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input signal.

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For example, if flipflop is in zero state, then the next state would be as one.

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If these were apparently for the transition from S1 to a zero, the input data should be zero on the

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rising edge of the clock.

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In other cases, the flipflop keeps its current state.

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To simplify the state transition diagram, visually draw only the transitional state links and the value

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of inputs and outputs.

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In the general case, the sequential circuit with end memory cells can have peer states, which at most

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is due to the power of an.

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Each state diagram should have a starting state from which the state transitions are started to perform

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a specific task.

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Usually we should have at least a path from each state to this Astarte state in order to receive the

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circuit, usually a recent signal in sequential circuits has a responsibility to putting the circuit

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into a known state.

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What is the is that signal characteristics and how to define that in the next lecture will answer these

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questions.

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These are our takeaway messages, this sets up a sequential circuit are defined by the logic values

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of its memory cells.

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The transitional state diagram can describe the behavior of a wide range of sequential circuits as they

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transition can occur by changes on the circuit clerk's signal and or the input signals.

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Now, the police question the road as they transition of the following search.