How is the effective state of a sequential logic circuit analysis determined?

You'll have to look at the status table to do that. For example, the present states Q2 n, Q1 N, and Q0 N are 000, 001, 010, 011, 100, 101, 110, 111, and the secondary states Q2 (N+1), Q1 (N+1), and Q0 (N+1) are 001, 011, 101, 111, 000, 010, 100, 110, and the output y is 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, Then you start drawing the state diagram, and then refer to the following diagram (state table), —

q2^n，q1^n，q0^n，q2^（n+1），q1^（n+1），q0^（n+1）， y。

- Start with 000, the present state of 000 points to the secondary state of 001, the present state of 001 points to the secondary state of 011, the current state of 010 points to the secondary state of 101, the key question comes, the current state of 101 points to the secondary state of 010 (000-->001-->011-->111-->110-->100-->000, here, the output is not drawn, the pointing of the arrow can be made on paper by yourself), here, Why are 010 and 101 invalid states, because when drawing a state diagram, they are not continuous in the state table, and they are directly skipped. Example of page84, "A Concise Course of Digital Electronic Technology Fundamentals (Third Edition)" edited by Yu Mengwei, Higher Education Press.

I hope you have a great holiday I'm reviewing my 2010 industry plan and I happen to have some questions for you.

Objective: To find out the change law of the state and output variables of the sequential logic circuit under the action of input variables and clock signals.

1. Analyze the circuit structure and write the driving equation of each flip-flop.

2. The driving equation is brought into the characteristic equation of the corresponding flip-flop to obtain the secondary state equation of each flip-flop, that is, the state equation of the sequential logic circuit.

3. Write the output equation according to the circuit diagram.

4. According to the equation of state and the output equation, list the state table of the timing belt circuit, and draw the state diagram or timing diagram.

Brief introduction. Sequential logic circuit is an important part of digital logic circuit, sequential logic circuit, also known as sequential circuit, which is mainly composed of two parts: storage circuit and combined logic circuit. It is different from other circuits that we are familiar with, its output state at any moment is determined by the input signal at that time and the original state of the circuit, and its state is mainly memorized and represented by the memory circuit.

At the same time, the particularity of the structure and function of sequential logic circuits is often difficult, complex and wide range of applications compared with other types of digital logic circuits.

The above content refers to: Encyclopedia - Sequential Logic Circuits.

The characteristic of a sequential logic circuit, in short, is that it has a memory function.

This is because the output signal of a sequential logic circuit is not only related to the input signal, but also to the state in which the circuit is located (i.e., it is able to remember its own logic state).

And the memory function is not available in combinatorial logic circuits.

A sequential logic circuit is a circuit composed of sequential elements (such as flip-flops, counters, etc.) and combined logic circuits, which have sequential and memorable properties. In practical applications, sequential logic circuits are widely used in computers, communications, control and other fields. For the analysis of sequential logic circuits, the following methods can generally be used.

Timing diagram method. The sequence diagram method is a graphical analysis method that visually represents the inputs, outputs, and state changes of a sequential logic circuit. When analyzing a sequential logic circuit, you can first draw a sequential diagram and then derive the input and output relationships of the circuit based on the sequential diagram.

The sequence diagram method is more practical in the analysis of simple sequential logic circuits, but the analysis efficiency of the sequential diagram method is low for complex sequential logic circuits.

State transition diagram method.

The state transition diagram method is a graphical analysis method of state, which can represent the state of the sequential logic circuit in the form of graphs, and describe the transition between states through the state transition relationship. When analyzing a sequential logic circuit, you can first draw a state transition diagram, and then derive the input and output relationships of the circuit based on the state transition diagram. The state transition diagram method is more practical and readable than the sequence diagram method when analyzing complex sequential logic circuits.

Temporal equation method.

The sequential equation method is an algebraic analysis method that converts a sequential logic circuit into a logical algebraic equation and solves the equation to obtain the input and output relationships of the circuit. When analyzing a sequential logic circuit, you can first convert the circuit into a logical algebraic equation, and then solve the equation to derive the input and output relationships of the circuit. The sequential equation method is useful for analyzing complex sequential logic circuits, but it requires a certain mathematical foundation.

There are many methods for analyzing sequential logic circuits, and different methods are suitable for different circuits. In practical applications, different analysis methods can be selected for circuit analysis according to the needs of the circuit in order to better understand and design sequential logic circuits.

The state of a sequential logic circuit is generally determined by a combination of its external inputs.

The output of a sequential logic circuit at any given moment depends not only on the input at that moment, but also on the input at each moment in the past. Common sequential logic circuits include flip-flops, counters, registers, etc. Because sequential logic circuits have the function of storing or memorizing, they are more complicated to overhaul.

The clock is the synchronization signal of the whole system, and when the clock fails, it will bring about the overall functional failure. Clock pulse loss will cause the system data master pulsation line, address bus, or control bus to become inactive. Changes in the rate, amplitude, width, shape, and phase of a clock pulse can cause failures.

In the digital circuit is usually divided into two categories: combinatorial logic circuit and sequential logic circuit, the relevant content of the combinatorial logic circuit has been introduced in the previous chapter, the characteristic of the combinatorial logic circuit is that the change of the input directly reflects the change of the output, and the state of the output only depends on the current state of the input, and has nothing to do with the original state of the input and output.

And it is related to the original state of the output state of Pan Gaoxiang, which is equivalent to adding a feedback input at the input end of the combinatorial logic, and there is a storage circuit in its circuit, which can maintain the state of the output, and we can use the block diagram of the following figure to describe the composition of the timing circuit.

Summary. Hello dear, I'm glad to answer for you, the sequential logic circuit analysis is 1) write the driving equation (input logic relation) of each flip-flop in the sequential circuit in the sequential circuit, and get the driving equation of the entire circuit. 2) Substituting the driving equation into the characteristic equation of the flip-flop to obtain the equation of state.

3) Write out the output equation.

Sequential logic circuit analysis.

Hello dear, I'm glad to answer for you, the sequential logic circuit analysis is 1) write the driving equation (input logic relation) of each flip-flop in the sequential circuit in the sequential circuit, and get the driving equation of the entire circuit. 2) Substituting the driving equation into the characteristic equation of the flip-flop to obtain the equation of state. 3) Write out the output equation.

Hello, I'm glad to answer for you, sequential logic circuits can be divided into two categories, one is called combinatorial logic circuits (referred to as combinatorial circuits), and the other is called sequential logic circuits (referred to as sequential circuits). The logic function of a combinatorial logic circuit is characterized by the fact that the output at any moment only depends on the input at that time, regardless of the original state of the circuit. The logic function of a sequential logic circuit is characterized by the fact that the output at any time depends not only on the input signal at that time, but also on the original state of the circuit, or in other words, on the previous input.