Computer Architecture Basics

Computer Architecture

• A computer is more than just a monitor and keyboard, it has internal components that capture user intentions and make them real.

The Mouse

• A mouse is a simple machine with buttons and a system for detecting motion and distance.
• It can use optical or mechanical (rubber ball and plastic wheels) systems for measurement.
• When a mouse button is clicked, it sends a message to the computer with information about its position.

Input/Output Subsystem

• The basic input/output subsystem acts as the eyes, ears, mouth, and hands of the computer, allowing it to interact with its environment.
• It acts as a buffer to prevent the CPU from being overwhelmed by distractions.

CPU and Interrupts

• The CPU (Central Processing Unit) is the brain of the computer, responsible for fetching instructions from memory and executing them.
• When the I/O subsystem decides that a mouse click is important, it generates an interrupt to the CPU.
• The CPU's job is to fetch and execute instructions from memory, and it can multitask by executing billions of instructions per second.

Programs and Memory

• There are programs for every task the CPU performs, written by humans in human-readable programming languages like Java, C++, or Python.
• Programs are compiled and made smaller, then stored in bits of ones and zeros in memory.
• The CPU looks up the address for the required program and sends a request to the memory subsystem for instructions.

Mouse Click Processing

• When the CPU receives a mouse click, it looks up the address for the mouse program and executes its instructions.
• The CPU may need to request instructions from other programs, such as the monitor program, to determine the action associated with the mouse click.
• The CPU fetches and executes instructions from multiple programs to complete the task, involving peripherals, the I/O subsystem, the CPU, programs, and memory.

Computer Architecture

• A computer consists of internal components that capture user intentions and execute them.

The Mouse

• A mouse is a simple machine with buttons and a motion detection system, which can be optical or mechanical.
• The mouse sends a message to the computer with its position information when a button is clicked.

Input/Output Subsystem

• The input/output subsystem acts as the interface between the computer and its environment, enabling interaction.
• It buffers the CPU from distractions, allowing it to focus on processing instructions.

CPU and Interrupts

• The CPU is the brain of the computer, responsible for fetching and executing instructions from memory.
• The CPU multitasks by executing billions of instructions per second.
• When the I/O subsystem detects an important event, such as a mouse click, it generates an interrupt to the CPU.

Programs and Memory

• Programs are written in human-readable languages like Java, C++, or Python and are compiled into smaller, machine-readable code.
• Programs are stored in memory as bits of ones and zeros.
• The CPU looks up the address for the required program and requests instructions from the memory subsystem.

Mouse Click Processing

• The CPU receives a mouse click interrupt, looks up the mouse program's address, and executes its instructions.
• The CPU may need to request instructions from other programs, such as the monitor program, to determine the action associated with the mouse click.
• The CPU fetches and executes instructions from multiple programs to complete the task, involving peripherals, the I/O subsystem, the CPU, programs, and memory.