Turing and Von Neumann Models

• The goal is to understand the core components of computer science
• This will cover the concepts of computer design as well as ethics
• Includes flashcard ideas

Turing Model

• A theoretical model for computation
• A machine manipulates symbols on a tape following defined rules
• Universal computation solves any computable problem via a Turing machine with the correct program
• Programmability dictates data processing, enabling varied outputs
• Different outputs come from the same input by altering the program
• Data Processor processes input data according to the program and provides output

Von Neumann Model

• This is the foundation of modern computer architecture
• The stored Program Concept stores both data and instructions in memory
• Sequential execution executes instructions in order
• Key subsystems in the model:
• Memory stores data and instructions
• Arithmetic Logic Unit (ALU) performs calculations and logical operations
• Control Unit manages and coordinates other subsystems
• Input/Output (I/O) Subsystem handles data exchange with the outside world

Computer Generations

• First Generation (1945-1956): used large, expensive, and unreliable vacuum tubes
• Second Generation (1959-1965): employed smaller and more reliable transistors; used high-level languages like FORTRAN and COBOL
• Third Generation (1965-1975): featured integrated circuits, further miniaturization, minicomputers, and software packages
• Fourth Generation (1975-1985): implemented microprocessors, personal computers (PCs), and desktop calculators
• Fifth Generation (Present and Beyond): includes artificial intelligence, voice recognition, and natural language processing

Computer Subsystems

• Central Processing Unit (CPU):
• Executes instructions and performs calculations
• Contains the ALU, control unit, and registers
• Main Memory:
• Stores data and instructions actively in use
• Consists of RAM (volatile) and ROM (non-volatile)
• Features a memory hierarchy of Registers > Cache > Main Memory > Secondary Storage
• Input/Output (I/O) Subsystem:
• Handles communication with peripherals like keyboards, mice, monitors, and storage devices
• Non-storage devices include keyboards and monitors
• Storage devices including HDDs, SSDs and CD-ROMs
• Interfacing uses I/O controllers which connect devices to the system bus
• Addressing:
• Isolated I/O uses separate address spaces for memory and I/O devices
• Memory-mapped I/O maps I/O devices to the memory address space

Different Architectures:

• CISC (Complex Instruction Set Computer):
• Uses large instruction sets and complex instructions
• Easier to program, but potentially less efficient
• RISC (Reduced Instruction Set Computer):
• Uses smaller instruction sets and simpler instructions
• More efficient, yet harder to program
• Pipelining: Overlaps instruction execution stages to enhance throughput
• Parallel Processing:
• Employs multiple processing units to perform tasks simultaneously
• Includes types like SISD, SIMD, and MIMD

Key Terms

• Turing Machine: A theoretical model that manipulates symbols on a tape based on defined rules
• Universal Computation: Solves any computable problem using a Turing Machine with the correct program
• Von Neumann Model: Foundation of modern computers, characterized by stored programs and sequential instruction processing
• Stored Program Concept: Data and instructions are stored in memory for flexibility
• ALU: Arithmetic Logic Unit, performing arithmetic and logical operations within the CPU
• Control Unit: Manages and coordinates all activities of computer components
• Registers: Small, fast memory locations within the CPU; temporarily holds data
• RAM: Random Access Memory is volatile memory to store code and data being acted on by the CPU
• ROM: Read-Only Memory containing non-volatile for permanent instructions for booting the computer

Computer Considerations

• Cache Memory: It is a small, high-speed memory type that stores frequently accessed data for faster retrieval
• I/O Subsystem: An input/output subsystem, handles communication between external devices and the computer
• Storage Devices: Are non-volatile, data is stored persistently on HDD, SSD, and CD-ROM
• CISC: Complex instruction set, uses larger more complicated instruction set, makes the programming potentially less efficient.
• RISC: Reduced instruction set, simple and efficient, requires more complex programming
• Pipelining: A method to improve throughput that overlaps the execution stages of multiple instructions
• Parallel Processing: Several instruction units are implemented to improve speed.

Number Systems

• They represent numerical quantities using symbols
• Different systems (decimal, binary, etc.) represent the same value with different symbols and rules

Positional Number Systems

• Digit position determines the value
• '1' is worth hundreds in '123', and '2' indicates tens
• General Formula: A number represented as (dn-1 dn-2 ... d1 d0 . d-1 d-2 ... d-m) in base 'b' and has the value (dn-1 * b^(n-1)) + (dn-2 * b^(n-2)) + ... + (d1 * b^1) + (d0 * b^0) + (d-1 * b^-1) + (d-2 * b^-2) + ... + (d-m * b^-m)

Common Number Systems

• Decimal (Base 10): Uses symbols 0-9
• Binary (Base 2): Uses symbols 0 and 1 - fundamental as it aligns with the electronic states (on/off)
• Hexadecimal (Base 16): Uses symbols 0-9 and A-F - makes representing binary data concise (4 bits = 1 hex digit)
• Octal (Base 8): Uses symbols 0-7 - Less common now, used in computing historically

Number System Conversions

• For Any Base to Decimal Conversion: Multiply a digit by its corresponding power, then sum
• Example: Convert binary to decimal
• For (110.11) the calculation is (1 * 2^2) + (1 * 2^1) + (0 * 2^0) + (1 * 2^-1) + (1 * 2^-2) = 6.75
• Decimal to any Base:
• Integral Part: Divide decimal number, take remainders, add to a new base
• Fractional Part: The fractional part is multiplied by the new base, add to integer parts
• These can be grouped
• Binary-Hexadecimal Conversion: Digits can be in sets of four
• Binary-Octal Conversion: Digits can be in sets of three
• Octal-Hexadecimal Conversion: These are done with converting with binary as needed

Key Reminders

• Number systems are essential for working with numerical information and computers
• Knowing conversions are essential when using hardware or software
• Using hexadecimal allows easy work with binary data.

Key Number System Conversions

• Number System: Represents amounts via symbols and rule
• Positional Number System: Where a digits value is what position it is
• Base(Radix): Digit used in a number system uniquely
• Decimal: Use base 10 with digits 0-9
• Binary System: A base 2 system, implementing digits 0 and 1
• Hexadecimal: Base -16 using letters A-F and digits 0-9
• Octal System: Implement base 8, using 0-7

More Conversions

• Convert (1011)_2 to Decimal, using (1 * 2^3) + (0 * 2^2) + (1 * 2^1) + (1 * 2^0) = 11
• Convert (2A)_16 to Decimal converts via (2* 16^1) + (10 * 16^0) = 42
• Convert (17)_8 to Decimal with(18^1) + (7 8^0) = 15
• Convert 12 to Binary provides 1100
• If extra, you can implement the number 30, this generates a Hexadecimal value of 1E
• Converting 25 to Octal provides the value 31
• Binary to Hexadecimal/Octal Conversion: This means you group binary digits in sets of 4, then each is converted to a hex
• Hex/Octal to Decimal Conversion: Now, digits can be multiplied by the base before added

Flashcard Tips For Number Systems

• Diagrams: Use diagrams visual aids(tables, charts, etc) to improve knowledge
• Reverse Questions: Generate new comprehensive questions ("What is 1101 in decimal?")
• Practical Applications: This asks commonly used systems by you

Numerical Data

• Different data types are stored and represented by a computer
• Represent integers with fixed-point
• Numbers come in the representation of floating-point or fixed-point
• Encoding schemes like ASCII and Unicode are used through text
• Digitizing is done through sampling, and quantization, and encoding

Data Storage

• Raster and vectors improve storing of images
• Videos are a sequence of images
• Logic operations occur through bit patterns
• Arithmetic and logical shifts uses change
• Integer operations come through complements and sign-magnitudes
• Calculations are calculated through floating-point

Numerical Data Deconstructed

• Numbers are all stores as bit patterns
• Patterns indicate which data and values can vary
• Memory is wasted when there is too much allocated volume to bit patterns
• Value missing will fill zero to the right

Number Types

• Integers: Fixed point formatting
  • Unsigned values: Only positive
  • Signed values: Positive and negative
  • Use complement or sign magnitudes
  • Compliment is a bit that is flipped
• Real Numbers: Using floating point formatting with sign, exponent, and Mantissa
  • Decimal normalization can come through the format +-d.xxxx
  • Binary is another formatting style
  • High memory use requires mantissa due to store requirements

Data Storage Encoding

• Represent text using encoding schemes
• Common is ASCII is codes (7 or 8 bit)
• Broader use comes from Unicode as it houses a wide range of languages
• Audios: Sample data through measuring to improve intervals
• Digital to analog quality: This impacts how it is transferred
• Sampling uses the one sound element by creating a base form

Visual and Quality

• Lossless provides an high audio quality with electrical components
• Quantization converts into amounts of integers
• Encoding is shown with patterns like MP3
• Pictures come in raster formats
• This includes sizes for Depth and quality
• Vector images for shapes and shapes
• Videos are high image display

Operations and Logic

• Bitwise:

o NOT: Flips the bit value (0 to 1, 1 to 0). o AND: 1 requires inputs of 1, return 0 otherwise o OR: Checks if at least one input is 1, otherwise 0 o Xor returns with at least one equal to 1, returning 0 otherwise

• Active changes and shifting
• Shifts happen from spaces
• Arithmetic operations are used for integer processing

Two and Key Considerations

• Twos operations improve the simple equations
• Simpler is magnitude
• Floating helps exponent alignments.
• Understanding operations and computers
• Know the science and usage of data.

Data Concepts

• Bit: Smallest computer data that can measure 0 or 1
• byte: A group of 8 bots will measure a character
• Fix location means decimal usage
• Floated points allows a wide value measuring

Data Manipulations

• Common standard for letters
• Wide usage is with coding
• Sampler measures waves and digits and waves
• Quantum can be used for audio levels
• Images use pixilation.

Logical Computing

• NOT inverts all bits, from 0 to 1 (or vice versa)
• The output of (AND) is only if the inputs are 1
• (OR) is made when given 1

Network and the Internet

• Aims: Understand computer connection and information
• Usage: Understand Internet systems

Primary Connections

• Internet is all things hooked on connection
• Hoster is devices that work through network
• Connectors allow modems connection
• Transmitting devices are those with media on
• Local is for networks
• Wide is through globe

A System

• The internet is for connections
• The core allows providers systems
• TCP is the dominate suite online protocol.
• Provides functions for networking

Levels to Internet Access Points

• Applies connections
• Services are on users

Data Usage

• Paradigm allows systems connections
• Layer transfer for connected services
• Sends data
• Addresses are important
• Internet Protocol (IP) IPv4 & IPv6

Ethernet Points

• Uses wire transfers for communication
• Wireless for networking
• Cables and technology improves

Networking Concepts Summary

• Enables computer connections
• Uses network model frameworks
• Important for communications
• There are a large amount of characteristics for everything
• Look at the more important details

Computer Science Overview

• Networking enable service connection between everything
• TCP model allows system understanding
• Key layers in the function connect each other
• Wireless connections improve network use

Important Connection Definition

• Networking links all, helping all share connections
• Hoster is used as a connected device
• Router pushes the connection
• Switches help the connections locally

Connections to Wireless

• LAN and Wireless networks allows a larger network
• Networking comes from all regions
• Connections on internet create TCP

Key Connections

• All connections use the same model to push data.
• Each layer can help communicate with information
• Physical layer is only used to transfer information bits.
• This module allows connections and network information

Operating System Considerations

• Learn how system help performance
• Learn how software works internally
• Allows more connections
• System allow useability

Primary System

• OS works with software to generate the management
• Aims efficient
• Process loads system memory
• Improves kernel loading

Essential Components

• Interface helps usage and interaction
• Helps through terminal commands
• Allocations and deallocation with processes
• Includes multiple functions
• Memory and system management between all

Usage of Queue

• Process execution management
• Stores computer
• Addresses for starvation and synchronizing

Device Manager:

• Manages control access
• Monitors status and polices
• Organizes what you access

OS List

• Unix is portable and powerful
• Helps stability
• Linux is similar with multiple distributions
• The popular ones are embedded systems
• Window is made by Windows improving compatibility

Key Takeaways

• There balance between the user and the system.
• Memory is a crucial aspect
• Knowledge is fundamental and important.

Key Term and Details

• System functions through software
• Bootstrapping loads operation memory
• Kernel does all
• The user uses interface
• Memory helps usage

System Usage

• Mono processes memory at rate
• Multi is concurrent sharing with core
• Virtual is illusion for data movement.
• It takes in consideration for everything
• Helps with security

Algorithm Actions

• Understands and solves problems
• Usage sequence
• Repetition helps process
• Visual presentation helps

Steps Implemented

• Algorithm acts for everything
• It is well defined by certain requirements
• All steps need to have a meaning and finite functions
• Input allows algotrithms to work on
• Execution allows steps implementation
• Algorithim helps output

Operations and Algorithm Logic

Loop : repetition happens through multiple steps Visuals : representation that shows how to implement systems Coding : implement English functions Basic : some adding and actions with it.

• There are limits that push information

Binary Algorithm

• Helps in some situation
• Needs sorted data
• High efficiency from high functions
• Time complexity is key
• Master data
• Improve connection performance
• Help with data management