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The basic structure of modern computer is made up of Von Neumann proposed ;
In von Neumann's architecture , Computers mainly have Arithmetic unit 、 controller 、 Memory （ That's memory ）、 input device 、 Output devices Five major parts make up ;
among Arithmetic unit and controller CPU;

2、 input device

For example, keyboard 、 mouse ;

3、 Output devices

Is the device that presents the calculation results , For example, a display 、 The printer 、 Sound, etc

4、 Memory

It's the memory of the computer ;

5、CPU: The arithmetic unit and register are collectively called the central processing unit

Arithmetic unit ： Doing arithmetic logic operations ;
controller ： Do control related operations ;

6、CPU The composition of the

7、 Internal bus

Connect CPU The wires of internal components are called internal bus ;

Be careful ：
The internal bus will be used in the examination questions 、 The system bus 、 External bus , Put them in the options respectively ;
Internal bus ： Only the internal bus of the chip ;
The system bus ： Patch panel level cable ;
External bus ： Line between equipment ;

3、 ... and 、 Which registers are included in the controller

Program counter （PC）： Address of the unit where the next instruction is stored ;
Instruction register （IR）： For preservation CPU Currently executing instructions ;
Instruction decoder ： Decode instructions , Then the instruction can be executed .
Timing unit ： It mainly sends out time pulse , Help us realize computer control .

understand ：
CPU While the program is running , When this instruction is completed, the next instruction will be executed , But how to find the next instruction ？ In the program counter, the address of the unit to execute the next instruction is stored , therefore CPU You can find where the next instruction to be executed is stored , then CPU Get the instruction according to the address ;CPU The fetched instruction will be put into the instruction register ; Then the instruction decoder decodes the instruction , Instructions will be executed .

Four 、 Which registers are included in the arithmetic unit

Arithmetic logic unit （ALU）: Perform arithmetic work , Responsible for arithmetic 、 Logic operation work .
Accumulation register ： Used exclusively for storage , Count 、 After logical operation One Of an operand or result of an operation .
Data buffer register ： Used to store operands or operation results and other related information .
Status condition register ： preservation CPU The state of being in an operation ;

5、 ... and 、 Test method 1：CPU Arithmetic unit in / The function of the controller

Ensure the correct execution of instructions ： control ;

6、 ... and 、 Test method 2：CPU The function of registers in

The number of bits in the instruction register depends on the length of the instruction to be stored ;
The capacity of the memory ： Determine how much content can be stored in memory ;
The width of the data bus ： Decide how many bits of data can be transmitted at the same time ;