Computer Systems: Structure, Components, and Programs
Item 9
Computer System Structure
1. Introduction
2. Basics
3. System Components
3.1. CPU
3.2. Memory
3.3. Peripherals
3.3.1. Peripheral Classification
3.4. Buses
3.5. System Functioning
4. Programs: Types and Features
4.1. Programming Languages
4.2. Operating Systems
4.2.1. Examples of Operating Systems
4.2.1.1. MS-DOS
4.2.1.2. UNIX
4.2.1.3. LINUX
4.2.1.4. WINDOWS
5. Computer Networks
5.1. Communication Networks: Internet
6. Conclusions
1. Introduction
The use of computerized systems, currently characterized by the prevalence of PCs in homes, businesses, and education, represents a significant social, economic, and labor revolution, alongside other mass media like press, radio, and television. To understand this, we’ll begin with basic concepts, then discuss the structure and components of computer systems and their operation. We will continue with programs, explaining their types and characteristics, and finally, we’ll cover computer networks, with a focus on the Internet. This topic is fundamental in the technology curriculum, applicable across various fields at the secondary education level.
2. Basics
- Decoder: A combinational circuit that converts a binary code input to its decimal equivalent.
- Logic Operation: Elementary computer actions connecting logic variables, such as AND (conjunction), OR (disjunction), and NOT (negation).
- Register: A small, high-speed memory for temporary data storage.
- Sequence: An ordered group of data or actions; a synonym is a succession.
- Logic Variable: A variable that can only be true or false.
- Random: Relating to chance or probability.
- Algorithm: A method for performing a task that:
- Covers all possible situations.
- Is objective and unambiguous.
- Is finite.
- Has a defined start and end point.
- Completes execution in a finite time.
- Algorithms are used to solve problems with computers, translated into programming languages.
- Microprocessor: A chip with integrated circuits performing central processing functions, typically including:
- A ROM with instructions.
- A register for the current instruction.
- A program counter (PC) with the instruction address.
- An Arithmetic Logic Unit (ALU).
- Additional registers for addresses and data.
- Some microprocessors have a small RAM for intermediate operations.
- CPU (Central Processing Unit): Executes actions described in a program or algorithm, including calculations processed in the ALU.
3. Structure, Components and their Operation
- All computers consist of the following blocks: CPU, main memory, peripherals, and communication buses.
- 3.1 CPU
- The CPU is the “brain” of the computer, executing programs stored in main memory by fetching, examining, and executing instructions sequentially.
- The CPU includes:
- Control Unit
- Arithmetic-Logic Unit (ALU)
- Working Registers:
- a) Program Counter (PC)
- b) Instruction Register (RI)
- The Control Unit fetches instructions from main memory and determines their type.
- The ALU performs arithmetic and logic operations, also known as the operational unit.
- Working registers are high-speed memory for intermediate results and control information. The Program Counter (PC) indicates the next instruction, and the Instruction Register (IR) holds the current instruction.
- The components work together: the control unit receives instructions from memory, storing them in the IR. The instruction decoder interprets them for the ALU. The PC increments synchronously after each instruction execution.