Overview
This lecture explained the basic structure and components of a computer system, focusing on the roles of hardware, software, the CPU, Von Neumann architecture, and data movement using buses.
Computer System Components
- A computer system consists of hardware (physical parts like CPU, RAM, hard disk, keyboard) and software (programs such as operating systems and applications).
- The CPU (Central Processing Unit) is the brain that executes instructions and manages input, output, and data storage.
CPU Structure and Function
- The CPU receives input, performs calculations, and outputs results.
- It can read from and write to memory, which is a form of input/output.
- The CPU consists of a Control Unit, Arithmetic Logic Unit (ALU), cache memory, and registers (small, fast memory areas with specific functions).
Von Neumann Architecture
- Modern CPUs are commonly based on the Von Neumann architecture.
- This architecture stores both data and program instructions in the same main memory.
- The stored program concept allows instructions and data to be moved one at a time to the CPU for processing.
- Main memory must be large enough to store both instructions and data.
Data Movement and Buses
- Data and instructions are transferred between the CPU and main memory via buses (wires on the motherboard).
- There are three main types of buses: control bus, address bus, and data bus.
- Each location in main memory has a unique address, similar to houses on a street.
- The address bus carries memory location addresses, the control bus sends control signals for operations (e.g., read/write), and the data bus carries the actual data.
Key Terms & Definitions
- Hardware — Physical parts of a computer (e.g., CPU, RAM, keyboard).
- Software — Programs that run on a computer.
- CPU (Central Processing Unit) — Executes instructions and manages data flow in the computer.
- Von Neumann Architecture — CPU design model with a single memory space for data and instructions.
- Bus — Electrical pathways connecting CPU and memory; includes control, address, and data buses.
- Register — Small, fast storage locations within the CPU for temporary data.
Action Items / Next Steps
- Review the roles of hardware and software in a computer system.
- Memorize the function of each bus and components of the Von Neumann architecture.