计算机中央处理器cpu_中央处理器（CPU）| 计算机科学组织

计算机中央处理器cpu

中央处理器(CPU) (Central Processing Unit (CPU))

The CPU is the brain of the computer system. It works as an administrator of a system.
CPU是计算机系统的大脑。它以系统管理员的身份工作。
All the operations within the system are supervised and controlled by the CPU. It interprets and coordinates the instructions.
系统内的所有操作均由CPU监控。它解释和协调指令。
The data and the instructions are temporarily stored in its memory unit. After performing operations, the result of operations can be stored in this memory unit.
数据和指令临时存储在其存储单元中。执行操作后，操作结果可以存储在此存储单元中。
The results of the operations are sent towards the output unit for the user.
操作结果将发送给用户的输出单元。
Thus, the CPU controls all internal and external devices, perform arithmetic and logical operations, controls memory usage and control the sequence of operations.
因此，CPU控制所有内部和外部设备，执行算术和逻辑运算，控制内存使用并控制运算顺序。
For performing all these operations, the CPU has three subunits:
为了执行所有这些操作，CPU具有三个子单元：
- Arithmetic and logic unit (ALU)
- Control unit
- Memory unit (CPU registers)

Arithmetic and logic unit is the subunit of the central processing unit as it is given above.
如上所述，算术和逻辑单元是中央处理单元的子单元。
It performs arithmetic operations like addition, subtraction, and logic operations like OR, AND, invert, exclusive – OR on binary words. The data stored in the memory unit is transferred to ALU. The ALU performs the operations that are the data is processed and the result is stored in an internal memory unit of the CPU. The result of a final operation is transferred from the memory unit to an output unit.
它对二进制字执行算术运算(例如加法，减法)和逻辑运算(例如OR，AND，取反，异或)。存储在存储单元中的数据将传输到ALU。 ALU执行以下操作：处理数据并将结果存储在CPU的内部存储单元中。最终操作的结果从存储单元传输到输出单元。
Arithmetic and logic operations performed by ALU sets flags to represent certain conditions such as equal to condition, zero condition, greater than the condition and so on. These conditions are checked by program instructions to change the sequence of program executions.
ALU执行的算术和逻辑运算设置标志来表示某些条件，例如等于条件，零条件，大于条件等。这些条件由程序指令检查以更改程序执行的顺序。

The control unit controls all the operations which internally take place within the CPU and also the operations of CPU related to input / output devices. The control unit directs the overall functioning of a computer system.
控制单元控制在CPU内部进行的所有操作，以及与输入/输出设备有关的CPU的操作。控制单元指导计算机系统的整体功能。
This unit also checks the correctness of sequence of operations. It fetches instructions in a program from the primary storage unit, interprets them and generates control signals to ensure correct execution of the program. The control signals generated by the control unit direct the overall functioning of the other units of the computer.
本机还检查操作顺序的正确性。它从主存储单元中获取程序中的指令，对其进行解释并生成控制信号以确保程序正确执行。由控制单元产生的控制信号指导计算机其他单元的整体功能。

A register is a group of flip-flops which can be used to store a word. It is a high-speed temporary storage space for holding data, addresses, and instructions during processing the instructions. Registers are not referenced by their addresses, however, they are directly accessed.
寄存器是一组触发器，可用于存储一个字。它是一个高速临时存储空间，用于在处理指令期间保存数据，地址和指令。寄存器不由其地址引用，但是可以直接访问它们。
To perform execution of the instructions, the processor contains a number of registers used for temporary storage of data and some special function registers.
为了执行指令，处理器包含许多用于临时存储数据的寄存器和一些特殊功能寄存器。
The special function registers include Program Counter (PC), Instruction Register (IR), Memory Address Register (MAR), and Memory Data Register (MDR).
特殊功能寄存器包括程序计数器(PC)，指令寄存器(IR)，存储器地址寄存器(MAR)和存储器数据寄存器(MDR)。

A program is a series of instruction stored in the memory. These instructions tell the CPU exactly how to get the desired result.
程序是存储在存储器中的一系列指令。这些指令准确地告诉CPU如何获得所需的结果。
It is important that these instructions must be executed in a proper order to get the correct result.
必须按照正确的顺序执行这些指令，以获得正确的结果，这一点很重要。
The sequence of instructions executions is monitored by the program counter.
指令执行的顺序由程序计数器监视。
It keeps track of which instruction is being executed and what the next instruction will be.
它跟踪正在执行的指令以及下一条指令。

It is used to hold the instruction that is currently being executed.
它用于保存当前正在执行的指令。
The contents of IR are available to the control unit, which generate the timing signals that control the various processing elements involved in executing the instruction.
IR的内容可供控制单元使用，控制单元生成控制执行指令所涉及的各种处理元件的定时信号。

These registers are used to handle the data transfer between the main memory and the processor.
这些寄存器用于处理主存储器和处理器之间的数据传输。
The MAR holds the address of the main memory to or from which the data is to be transferred.
MAR保留要向其传输数据的主存储器的地址。
The MDR sometimes also called MBR (Memory Buffer Register) contains the data to be written into or read from the addressed word of the main memory.
MDR有时也称为MBR(内存缓冲寄存器)，包含要写入主存储器的寻址字中或从中读取的数据。

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