Write in front: engaged in front-end development for several years, a lot of basic computer knowledge learned in the university are gradually fuzzy, plan to review the computer courses once, tamp the foundation, the future will go more steadfast, this is a continuous update of the article……

1. Composition and system of computer: from top to bottom: high-level language (Java,JS)– assembly language (ADD,SUB symbolic language)– operating system language — machine language (0,1 binary)– microinstruction system

2. Software that translates high-level language programs into machine language programs is called a translator. There are two kinds of translators: compilers and interpreters. Compiler: Translate all high-level language programs into machine language programs at one time, and then execute them. Interpreter: execute immediately after each translation of a high-level language program, that is, execute one translation.

3. Computer components: Main memory (main memory or memory) :

  • The main working mode is according to the address number of the storage unit to the storage word bits of storage (write) take (read). Access by address
  • To enable per-address access, main memory contains MAR(store address) and MDR(store data) registers.

Arithmetic unit

  • Contains at least 3 registers ACC(accumulator), MQ(multiplicator), X(operand) and arithmetic logic unit (ALU).

The controller

  • It is necessary to complete the reading, analysis and execution of an instruction.
  • Contains program counter (PC), instruction register (IR), control unit (CU).
    1. Program counter: store the address of the current pre-executed instruction, and MAR in the main memory has a path connection, with the function of automatic +1 to form the address of the next instruction.
    2. Instruction register: store the current instruction, IR content from MDR, opcode into CU, OP(IR) -> CU, used to analyze the instruction. The address code is stored as the address of the operand in MAR, denoted as Ad(IR) -> MAR
    3. Control unit: CU is used to analyze the operation required by the current instruction and issue a sequence of microoperation commands

I/O: Input (keyboard) and output (printer) devices

4. Computer hardware structure

  • Bus:

Among the five components, each component individually connected to each other is called decentralized connection, and connecting each component to a group of common information transmission lines is called bus connection.

  • memory

  • Input output system