What form does the controller belong to?

What is the operation controller in CPU?

The answer is provided by Baidu Encyclopedia:

Each functional unit in the CPU performs a specific function. However, how can information

What about the transmission between components? In other words, which components control the data flow? Usually put a lot.

The path of information transmission between digital components is called "data path". Where does the information begin, the middle paragraph

It is necessary to control which register or multi-way switch is passed through and which register is finally passed to. In each register

The task of establishing data path is completed by a component called "operation controller".

The operation controller OC mainly includes control logic such as beat pulse generator, control matrix, clock pulse generator, reset circuit and start-stop circuit. These components are very important for microprocessor designers, but microprocessor users don't have to care too much.

function

The function of the operation controller is to generate various operation control signals according to instruction operation codes and timing signals.

Establish the data path correctly, so as to complete the control of fetching and executing instructions.

Basic process of instruction execution 1. Instruction fetch: according to the instruction address (provided by PC), fetch the instruction to be executed from the memory.

2. Analysis and explanation:

(1) decoding analysis. Determine the operation that the instruction should complete and generate the control potential of the corresponding operation. Participate in all control commands (micro-operation control signals) required to form instruction functions.

(2) According to the analysis of the addressing mode and the functional requirements of the instruction, the effective address of the operand is formed, and the operand (operation instruction) or transfer address (transfer instruction) is taken out according to this address to realize the program transfer.

3. Execute the instruction: according to the operation control signal generated by the instruction analysis and the formed effective address, an instruction control sequence is formed according to a certain algorithm to control relevant components to complete the functions specified in the instruction.

Common control mode

The common control methods of operation controller are synchronous control, asynchronous control and joint control.

Synchronous control mode: the operation of any instruction or the execution of each micro-operation in an instruction is controlled by a definite time sequence signal with a unified reference time scale. That is, all operations are controlled by a unified clock and completed within the standard time. (Under synchronous control, the end of each time sequence signal means that the scheduled work has been completed, and then the subsequent micro-operation is started or automatically transferred to the next instruction. )

Asynchronous control mode: there is no unified synchronization signal, and the question-and-answer mode is used to coordinate the time sequence, and the answer of the previous operation is used as the start signal of the next operation.

Joint control mode: the combination of synchronous control and asynchronous control. Its overall design idea is: the functional components adopt synchronous mode or control mode based on synchronous mode; Asynchronous mode is adopted between functional components.

What are the meanings of synchronous control mode and asynchronous control mode of controller, and what are their characteristics?

Overview of hello synchronous controller: it refers to coordinating the position, speed and torque between master and slave according to a certain proportion. There are usually two types of synchronous controllers. One is used together with the tension system, and the other is the space positioning controller, which is position synchronization.

Main characteristics of synchronization: 1. Digitization II. Powerful 3. High precision 4. Universality.

Overview of asynchronous controller: When the controller sends a control signal to execute a micro-operation, wait for the "reply" signal or "end" signal sent back by the execution part after completing this operation, and then start a new micro-operation, which is called asynchronous control mode.

Features: The micro-operation sequence formed by asynchronous control has no fixed cycle beat and strict clock synchronization, so each instruction takes as much time as it takes.

Talk about how the navigation controller uinavigationcontroller manages the controller.

The navigation controller manages a series of scenes displaying hierarchical information. It creates a view manager "stack" with the root view controller at the bottom. When users switch between scenes, they push the trial controller into the stack in turn, and the trial controller of the current scene is located at the top of the stack. To return to the previous level, the navigation controller will pop up the controller at the top of the stack, thus returning to the controller below it.

The navigation controller also manages the UINavigationBar. The navigation bar is similar to a toolbar, but it is filled with an instance of UINavigationItem, which is added to every scene managed by the navigation controller. By default, the navigation item of the scene contains a title and a back button. The back button is added to the navigation item in the form of UIBarButtonItem.

Navigation items have three settable properties in the Property inspector panel: title, prompt and back button.

Title-the title of the navigation item

Tip-The text displayed above the title to provide instructions to the user.

Back button The text of the back button for the next scene. If it is not set, the text displayed by default is the title.

In any case, you can get the navigation controller through the parentViewController property.

UINavigationController is divided into three parts: the navigation bar at the top, the custom content in the middle and the navigation toolbar at the bottom.

What is an electrical control circuit? What are the representations?

Simply put, the control circuit is the secondary circuit. First of all, what is the primary circuit? What is the secondary circuit? The primary circuit refers to the main circuit with large current, and the secondary circuit controls the primary circuit in various ways, such as button contactor, intermediate relay, PLC, DCS, etc. The representation of the control circuit can be divided into: the primary circuit current is large, and the basic current of the control circuit can be ignored!

What is process control?

The process control mode of production activities is a control mode for daily control of the ongoing production system. After-the-fact control has played a role in mending the situation, and it is inevitable that it is too late. Can it be effectively controlled in production activities? Quality control chart method realizes this idea in quality management, which marks the emergence of process control. The process control mode uses feedback information to implement control. Obtain information through operation accounting and field observation, compare and analyze the output with the control target in time, formulate control measures to correct the deviation, continuously eliminate the adverse consequences caused by interference, and ensure the realization of the planned target. Process control activities are regular and have been going on. Obviously, its control focus is the current production process, and production activities should be placed under strict control to ensure the smooth implementation of the plan. Some people call it consumption management vividly, that is, the management of manpower and material resources spent today. Process control can avoid unplanned losses, but frequent control activities themselves also need to pay a price. The key points of the control mode in the event are: 1, based on the information obtained during the implementation of the plan; 2. Need complete and accurate statistical data and complete on-site activity information; 3. Have an efficient information processing system; 4, rapid decision-making, strong execution, to ensure timely control.

According to the form of control system signal, which two control systems can the control system be divided into?

Microprocessor is the core part of microcomputer, also called Central Processing Unit (CPU). Microprocessor is mainly composed of controller and arithmetic unit (as well as some supporting circuits) to complete the interpretation and execution of instructions. The arithmetic unit in CPU is composed of arithmetic logic unit ALU, accumulator AC, data buffer register DR and flag register F, and it is the data processing part of computer. We take a simple addition operation of two numbers A and B as an example to illustrate the operation steps of each part of the operator. Calculate A+B 1) take out the first addend a from the main memory m and send it to the accumulator AC for temporary storage via the bidirectional data bus DB, the data buffer register DR and the arithmetic logic unit ALU; 2) take out another addend b from the main memory m and send it to the data buffer register DR for temporary storage through the bidirectional data bus d b; 3) Under the action of the control signal, the numbers A and B are taken out from AC and DR respectively, and sent to ALU for addition operation, and the addition result is written back to gallbladder accumulator AC, and the flag states reflecting the operation result such as "zero", "negative", "carry" and "overflow" are written into flag register F; 4) The sum of two numbers in 4)AC is sent to the main memory for storage through DR and data bus DB. The above process can be symbolized as: (a)->; DR； (Doctor)-> AC； (B)——& gt； DR； (AC)+(DR)—& gt； AC； (communication)-> DR； (Doctor)-> M. As can be seen from the above example, the arithmetic unit should have the following basic functions: 1) It has the operation ability to process data, such as arithmetic operations such as addition, subtraction, multiplication and division, and logical operations such as AND, OR AND NOT. These tasks are completed by arithmetic logic unit ALU; 2) It has the ability to transmit data and temporarily store the data involved in the operation and some intermediate operation results, which is generally completed through the internal data transmission bus and general registers; 3) It has the function of selecting the data to be involved in the operation and the operation to be performed, and can send the operation result to the designated part according to the instruction requirements. This part of the function is mainly realized by a large number of electronic control devices in the arithmetic unit. The control part in CPU consists of instruction counter IP, instruction register IR, instruction decoder ID and corresponding operation control components. It produces various control signals to make all parts of the computer work in harmony, and it is the instruction execution part of the computer. The main working principle of the controller and the functions of each component are as follows: 1) instruction fetching: according to the contents of the instruction counter IP (instruction address), an instruction to be executed is fetched from the main memory through the address register AR and sent to the instruction register IR; At the same time, make the IP content point to the address of the next instruction to be executed (generally by adding 1 to the IP content); 2) Analyze instructions: also known as instruction decoding, the instructions stored in the instruction register IR are analyzed by the decoder ID, and corresponding operation commands are generated according to the requirements of the instructions. If the data involved in the operation is in main memory, the corresponding operand address needs to be formed; 3) Execution of instructions: corresponding operation control signals are formed according to the operation commands and operand addresses obtained in the instruction parsing process, and the functions of each instruction, including processing the operation results and forming the next instruction address, are realized through the arithmetic unit, main memory and I/O device execution signals; 4) Repeat the above steps, then fetch the instruction, analyze the instruction, execute the instruction, and so on, until you encounter the shutdown instruction or get external intervention. In microcomputers, instruction fetching and instruction analysis are often called instruction fetching, so the process of computer completing an instruction is divided into two steps: instruction fetching and instruction execution. The time to execute an instruction is called machine cycle. Machine cycle can be divided into instruction fetch cycle and instruction execution cycle. The instruction fetch cycle of any instruction is the same, but the instruction fetch cycle of executing instructions is different. Because of the different nature of instructions and the different operations to be completed, the execution cycle of different instructions is also different. The main registers in the CPU perform their respective functions and complete specific functions. How to control the transfer of information between specific registers, that is, how to control the flow of data, can be instructed by the computer. & gt

According to the function of computer in the system, what types can computer control systems be divided into?

Classification of computer control systems

There are three classification methods of computer control system: automatic control line classification, participation control method classification or regulation law classification.

A, with automatic control line classification

In automatic control mode, it can be divided into the following categories:

(1) computer open-loop control system

If the output of the computer open-loop control system can control the production process, but the control result-the state of the production process does not affect the computer control system, and the computer, controller, production process and other links do not form a closed loop, it is called a computer open-loop control system. As can be seen from the figure, the state of the production process is not fed back to the computer, but the operator monitors the state of the production process, decides the control scheme, and tells the control computer to exercise the control function.

(2) Computer closed-loop control

When a computer controls a production object or process, the state of the production process can directly affect the computer-controlled system, which is called a computer closed-loop control system. Under the supervision of the operator, the control computer automatically accepts the detection results of the production process state, calculates and determines the control scheme, directly directs the actions of the control elements (devices), and exercises the role of controlling the production process.

In such a system, the control part controls the running equipment according to the control information sent by the controller, and on the other hand, the running state of the running equipment is taken as the output, which is measured by the detection part and fed back to the control computer as the input; So that the control computer, control components, production process and detection components form a closed loop. We call this control form computer closed-loop control.

Computer closed-loop control system, using mathematical model to set the deviation between the optimal value of production process and the feedback value of test results, controls the production process to run in the optimal state.

(3) Online control

As long as the computer can directly control the controlled object or the controlled production process without manual intervention, it is called control computer online control or online control system.

(4) Offline control

The control computer does not directly participate in the controlled object or the controlled production process. It only completes the state detection of the controlled object or process, and processes the detected data. Then, the control scheme is formulated, and the control instruction is output. The operator refers to the control instruction and manually operates the control component to control the controlled object or process. This control form is called computer off-line control system.

(5) Real-time control system

Control computer real-time control system refers to the controlled object or process. Whenever there is a processing or control requirement, the controller can process and control it in time. This method is often used in the occasion of intermittent production process. For example, steelmaking is a process. Another example is the steel rolling process. Every piece of steel is counted as a process, and each process is repeated. Only when you enter the process, you need a computer to control it. Once the computer controls it, it is required to respond or control the information from the production process within a specified time. This system is often realized by using a perfect interrupt system and interrupt handler. To sum up, an online system is not necessarily a real-time system, but a real-time system must be an online system.

Secondly, the ways of participating in control are classified.

According to the control mode of the control machine, it can be divided into the following categories:

(A) direct digital control system

The control computer replaces the traditional analog regulating instrument and directly controls the production process. Because the signal from the computer is digital, it is named DDC control. In fact, the control part of the controlled production process can convert the digital control quantity output by the computer into analog quantity through the D/A converter in the process input/output channel of the controller. The A/D converter that controls the process input/output channel of the computer also converts the input analog quantity into digital quantity.

In DDC control system, small computers or microcomputer time-sharing systems are often used to realize multi-point control functions. In fact, it belongs to discrete sampling with controller to realize discrete multipoint control. This DDC computer control system has become one of the main control forms of computer control system at present.

The advantages of DDC control are great flexibility, high centralized reliability and low price. The production process of several circuits or even dozens of circuits can be controlled by digital operation. & gt

What is the control mode of frequency converter?

Generally speaking, variable frequency control methods include: open-loop vector control, V/F control, open-loop torque control, closed-loop vector control and so on.

Open loop vector control

It is suitable for high-performance general occasions where there is no encoder PG and only one motor can be driven by one frequency converter. Such as machine tools, centrifuges, wire drawing machines, injection molding machines and other loads.

V/F control

Suitable for occasions with low control accuracy, such as fans and pumps. It can be used in the situation where a frequency converter drives multiple motors.

Open-loop torque control (no PG vector control)

Suitable for winding, wire drawing and other occasions where torque control accuracy is not high. In the torque control mode, the motor speed is determined by the motor load, and its acceleration and deceleration speed is no longer determined by the acceleration and deceleration time of the frequency converter.

Tip: When choosing vector control mode, there must be self-learning of motor parameters. Only by obtaining accurate motor parameters can we give full play to the advantages of vector control.