Principles of Computer Organization Chapter 1 Overview of Computer Systems

1. Introduction to Computer System

1. Describe the hierarchical structure of a computer system?

1. Classification and some examples of system software?

Tips: To determine whether it is system software and application software, first of all, from the perspective of whether to manage hardware, it is roughly divided into the following categories

1. Features of von Neumann computers? (6)

1. The computer is composed of five major components
2. Instructions and data stored in memory at the same position, according to an address search (think about how to differentiate instruction and data memory? Different phases of the instruction cycle )
3. Instructions and data are represented in binary
4. Instruction by the operation code and address code consisting of
5. Instructions are stored sequentially in memory
6. With the operator as the center, the data transmission between the I / O and the memory is completed by the operator (leading to low transmission efficiency, and the memory has been used as the core)

1. Von Neumann computer, computer hardware block diagram, modern computer hardware block diagram

1

.Von Neumann Computer Hardware Block Diagram

 

2. Modern computer hardware block diagram centered on memory

3. Block diagram of modern computer hardware

Among them, ALU is the arithmetic unit, and the controller is the main memory of the CU and the controller.

The memory is divided into: main storage and auxiliary storage

I / O device representatives: input devices and output devices

The arithmetic unit performs arithmetic operations and logical operations

Memory is used to store data and programs

The controller is used to direct the program to run

The input device converts the information into a form that the machine can recognize

The output device converts the operation results into a form familiar to humans

1. Computer system: hardware (modern calculator hardware) + software (system software and application software)

1. Operator

	ACC	MQ	X
addition	Addend with		Addend
Subtraction	Subtracted difference		Minus
multiplication	Product high	multiplier Product low	Multiplicand
division	Dividend remainder	Quotient	divisor

 

1. Memory (storing data and programs (instructions))

Storage body: Building Storage unit: Room Storage element: Bed

Storage unit: store a string of binary codes (each storage unit is assigned an address number)

Storage word: combination of binary codes in the storage unit

Storage word length: the number of binary codes in the storage unit (MDR response)

MAR: Memory Adress Register-> memory address register

     Used to reflect the number of storage units

MDR: Memory Date Register-> Memory Data Register

     Used to reflect the storage word length

Eg: Set MAR = 4 bits to represent 0000-1111, which is the 4th power of 2, that is, a total of 16 storage units, and MDR = 8 bits, that is, the storage word length is 8 bits (1 byte), a total of 16B

 

1. Controller

1. The whole process of computer work (take the number as an example, answer the host to complete the process of an instruction)

Send the program to the computer through the input device, the first address of the program-> PC

Start the program: PC-> MAR-> M-> MDR-> IR

              Analysis instruction OP (IR)-> CU

              Execute instruction Ad (IR)-> MAR-> M-> MDR-> ACC

Where Ad (IR) refers to the address code in the fetch instruction

1. Computer Performance Index

1. machine word: CPU process makes a number of data bits, and the CPU register bit numbers in the relevant

The more digits in the word length, the higher the precision and the faster the operation speed

2. Storage capacity stores the total number of binary digits

3. Calculation speed:

   Main frequency

   Gibson method (the execution time of each instruction and their percentage in all operations

   MIPS: execute millions of instructions per second

   CPI: the number of clock cycles required to execute an instruction

   FLOPS: floating-point operations per second

11. Instructions and data are stored in memory, how does the computer distinguish them?

1. Through different time periods: the instruction is fetched during the instruction fetch phase, and the instruction fetched as data during the instruction fetch phase

2. Via the address source: the storage unit address provided by the PC is fetched by the instruction, and the storage unit address provided by the instruction address code is the operand.