Computer Systems Basics

Computer Systems

• A computer is a programmable electronic device that can store, process, and communicate information.
• Fixed computers are designed to perform a single task, while programmable computers can be programmed to perform a variety of tasks.
• Calculators are limited to basic arithmetic operations, whereas computers can perform complex calculations and store data.

Input and Output

• Input devices: keyboards, scanners, microphones, cameras
• Output devices: monitors, speakers, printers, projectors

RAM and ROM

• RAM (Random Access Memory): volatile, stores data temporarily while the computer is running
• ROM (Read-Only Memory): non-volatile, stores data permanently, even when the computer is turned off

Secondary Storage

• Necessary for storing large amounts of data when the computer is turned off
• Types: magnetic (hard drives, floppy disks), optical (CDs, DVDs), solid-state (flash drives, SSDs)
• Technologies used: magnetic, optical, solid-state

CPU

• ALU (Arithmetic Logic Unit): performs mathematical operations
• Busses: pathways for data transfer between components
• Clock: regulates the pace of operations
• Registers: small amounts of on-chip memory
• Control Unit: manages data flow and instruction execution

Operating System

• Manages memory, program execution, input/output, and user interface (GUI)
• Manages communication between hardware and software

Binary

• A base-2 number system using 0s and 1s
• Convert denary (base-10) numbers to binary: division by 2, remainder becomes the binary digit
• Convert binary to denary: sum of (binary digit * 2^n)

Binary Maths

• Add three binary numbers together using the standard rules of arithmetic

Data Sizes

• bit: single binary digit
• nibble: 4 bits
• byte: 8 bits
• kilobyte (KB): 1024 bytes
• megabyte (MB): 1024 KB
• gigabyte (GB): 1024 MB
• terabyte (TB): 1024 GB

Algorithms, Computational Thinking, and Python

• Abstraction: breaking down complex problems into simpler parts
• Decomposition: breaking down problems into smaller, manageable parts
• Pattern recognition: identifying patterns to solve problems
• Algorithm: a set of instructions to solve a problem
• Representing Algorithms: flowcharts, pseudocode

Computational Thinking

• Sequence: the order of steps in a program or algorithm
• Selection: using if-else statements to make decisions
• Iteration: using loops to repeat tasks

Python Programming

• Variables: store and change values in a program
• Selection: if-else statements
• Data Types: numbers, strings, booleans
• Iteration: while loops, for loops

AI Experience

• AI: Artificial Intelligence, creating intelligent machines
• Rule-based programming: using fixed rules to solve problems
• Data-driven programming: using data to make decisions
• Types of AI: Machine Learning, Narrow AI, General AI

Machine Learning

• Supervised Learning: labeled data, learns to map inputs to outputs
• Unsupervised Learning: unlabeled data, discovers patterns
• Reinforcement Learning: learns through trial and error
• Semi-supervised Learning: combination of supervised and unsupervised learning

AI Lifecycle

• Defining the problem
• Preparing Data
• Training
• Testing
• Evaluating the Model

Machine Learning: Data Preparation

• Cleaning: removing duplicates, missing, and invalid data

Machine Learning: Testing

• Bias: testing for bias in data
• Measuring accuracy and confidence
• Bias in, bias out: model reflects the bias in the data

Decision Trees

• A visualization of decisions and possible outcomes
• Made by training a model on data

Physical Computing with Picoboards

• Electronic Components:
  • Breadboard: for prototyping electronic circuits
  • Jumper wires: connect components
  • LED: light-emitting diode
  • Resistor: controls voltage
  • Sensor: detects changes in environment
  • Motor driver: controls motor speed
  • Power supply: provides voltage
  • Buttons: inputs
  • Buzzers: outputs

Electricity and Frequency

• Electron flow: flow of electrons in a circuit
• Typical voltage levels: 3.3V, 5V, 9V
• Frequencies: Hertz (Hz), e.g., 50Hz, 60Hz

Picoboard

• GPIO pins: for input/output
• USB connector: connects to computer
• CPU: central processing unit
• LED: onboard light
• Debug pins: for debugging
• GND pins: ground connections
• Power pins: power connections

Microcontrollers

• Purposes: control devices, interact with sensors, etc.
• Examples: robotic arms, home automation systems