concept

Relationship: The same information can be represented by different data

Difference: Data is the specific manifestation of information and the carrier of information, while information is the result of processing data.

Related technologies for people to acquire, store, transmit, develop and utilize information resources

Main technologies: sensing technology, computer technology, communication technology, network technology

1946 ENIAC, University of Pennsylvania, USA

EDSAC first computer using von Neumann architecture 1949

EDVAC, the first modern general-purpose computer in 1951, was binary and consisted of arithmetic units, controllers, memory, input devices, and output devices.

First generation (1946-1956)

Second generation (1956-1964)

The third generation (1964-1971)

Fourth generation (1971-present)

Shannon, information theory

Wiener, cybernetics

Von Neumann, stored programs, principles of program control

Turing, mechanical computer

Fast computing speed

High calculation accuracy

Large storage capacity

Ability to make logical judgments

Work automation

subtopic

Processing object

use

scale

application

Giant, miniaturized, intelligent, networked

Number system: Calculation using the carry principle is called carry calculation value

Number: a symbol used to represent a certain number system

Base: the number of digits

Positional weight: the weight of numbers in different positions

Ten: D Number: 0-9, base: 10, weight: 10

Two: B 0, 1, 2, 2

Eight: O 0-7, 8, 8

Sixteen: H 0-9 A-F, 16, 16

arithmetic operations

logic operation

Bit (bit) b The smallest unit doubles the number represented by each additional bit.

Byte (byte) B 1B=8bit Byte is the basic unit of storage information B M G T

Word (word) data that the CPU accesses, processes and transmits at one time through the data bus

Word length: the number of bits of binary data that the computer's arithmetic unit can process simultaneously, unit: bits

BCD code (8421)

Non-numeric type (character encoding ASCII code)

A command that instructs the computer, binary

Collection of all commands: command system

ideological system

Basic idea: stored programs and program control

fetch instructions

Analysis instructions

Execute instructions

Instruction cycle: the time from fetching the instruction to executing the instruction

Memory (main memory)

External memory (auxiliary memory)

Operating System OS The direct interface between users and computer hardware systems

Language processing system: source program needs to be translated and executed: assembler, compiler, interpreter

System support and service programs: editing programs, anti-virus software

Database management system DBMS

Procedure: A description of the steps to solve a specific problem

Program = Algorithm Data Structure

It is a language used by users to write certain programs and a tool for exchanging information between humans and computers.

From the perspective of describing the objective system

Structured program flow: sequence → selection → loop

development path

Microcontroller single board computer PC personal computer portable microcomputer

Main frequency: determines the running speed of the computer, HZ

Word length: addressing capability

Number of cores: The number of operators and controllers connecting each processor core through a parallel bus

Memory capacity: total bytes

Operation speed: Number of instructions executed per unit time, MIPS=10^3BIPs

The higher the main frequency, the longer the word length, the smaller the storage cycle, the larger the memory capacity, the faster the computing speed and the better the performance.

bus

motherboard

input device

output device

microprocessor

memory