Computer Systems: Hardware & Architecture

Computer Systems - Unit 1

• Computing systems consist of one or more processors, a control unit, and peripherals, including firmware and software that are essential for operation.
• Information and Informatics encompass the structure of a computer, hardware, software, units of measure for information quantity, and computer architecture.
• Key computer components include processors and memory types and also incorporate characteristics, ROM-BIOS, boot processes, setup configuration parameters, PC external connections (port types), peripheral devices (classifications), and also backup copies.

Data vs. Information

• Data is a symbolic representation of facts, concepts, or instructions.
• Data Examples are numerical, alphabetical, or algorithmic attributes that describe empirical events or entities.
• Data can be objective, subjective, qualitative, or quantitative, coming from internal or external sources.
• Data on a football team's members, such as names, addresses, and contact details, is considered their own data.
• Data is the smallest unit of semantics, and it corresponds to primary information.
• Data alone is insufficient to support decision-making and does not provide insight or direction.
• Data can be stored physically (paper), electronically (CD, DVD, hard drive), or in memory, aided by information technologies.
• Information is a structured set of data meant to convey meaning, reduce uncertainty, and increase knowledge.
• Taking the example of the sound of a train horn, its meaning varies based on context and recipients.
• The horn indicates the train's arrival for passengers, signals drivers to stop, and indicates nearing the destination of those on board.
• The meaning of information is thus determined by timing, context, the receiver, and their needs.
• The key distinction between data and information is that data only becomes useful once it is processed and converted into a meaningful format, which results in information.
• Knowledge combines experience, values, and information to provide a framework for incorporating new information and action.
• Knowledge comes from data, and information comes from data, facilitating actions like comparison, prediction, connection-seeking, and conversation.
• Information is valuable because it enhances decision-making by reducing uncertainty and increasing the likelihood of success.
• Accurate decisions depend on reliable and truthful information, similar to how enterprises succeed through quality and verifiable data.
• Information combines processed data with relevance, purpose, and context to reduce uncertainty and inform actions.

Qualities & Obtaining Information

• For information to fulfill its purpose and aid in decision-making, it needs key qualities: oportune and adequate.
• For information to be opportune, it must reach the user in a timely fashion.
• Data accuracy ensures correctness, completeness provides all elements for sound decisions, significance is relevant and understandable, coherence lacks contradictions, and relevance excludes unneeded information.
• Information comes from processing data, using basic operations that transform data into information.
• Basic operations include capturing, verifying, classifying, ordering, summing, calculating, storing, retrieving, reproducing, and distributing data.
• Informatics was coined in 1962, originating from informaticion and automatique, later adapted in 1968, referring to automatic information processing.
• Informatics is a set of disciplines and technologies treating information systematically for knowledge, decision-making, conservation, and communication.
• The Royal Spanish Academy defines informatics as the scientific and technical knowledge which enables automate and rationalize information through computers.
• Automatic treatment is the ability of machines to capture, process, and present information, while rational treatment entails regulated processing via programs that mimic human reasoning, achieving "automatic treatment" by computers.

Computing Systems: Definition & Structure

• A computational system can be described as one or more processors with respective control units and necessary peripherals, inclusive of firmware and software for operability; formal use constitutes its functionality.
• A Computer is defined as a digital electronic and synchronous machine capable of numerical and logical calculation controlled by a stored program and able to interface with external environments.
• Within a computer, electrical signals representing data are handled in discrete forms using the binary digits 0 and 1.
• Operations coordinated by a central clock ensure synchronized actions among all its components.
• Computing has both numerical and logical processing capacity residing in a subsystem called the Arithmetic Logic Unit (ALU); operations normally include arithmetic, disjunction, conjunction, and comparison tasks that are simple.
• The computer is controlled by stored programs, which differentiates it from calculators.
• Stored instructions are executed internally, and a computer device communicates with the external world.
• The computer can input and output values using appropriate peripheral devices; the real world is recognized as analog, whereas computers are digital and operate through input, processes, and outputs.
• Input- the entry of data into the system.
• Processing- actions inside the computer.
• Output- retrieval of desired info.
• Computers consist of hardware (physical components) and software or programs (which control and coordinate the hardware to manage computer resources and operations).
• Software is intangible, including the operating system, programming software, and specific applications.
• Computers require both hardware and software for practical use.
• Programs are sets of instructions; coding programs is called programming.
• The two types of software are system software (operating system) and applications software.

Software Types

• System software manages computer resources such as the central processor, communication links, and peripheral devices.
• Programming software is used to create new programs in a specific programming language.
• Application software is designed to perform specific tasks by individual users or teams.
• Application software may run on specific operating systems or be cross-platform; examples include Microsoft Word, spreadsheet programs, graphic editors, and multimedia managers.
• System software administers tasks by preparing, scheduling, and monitoring activities, and also controls use of resources by system and application software; management of data controls data flow, storage, and data retrieval.
• Core components of system software are the device controllers (BIOS, firmware, drivers) and the operating system, which manages computer resources and user interaction.
• Utility software further supports by analyzing, configuring, optimizing, and maintaining computers.
• Low-Level Software is much like machine code that uses binary to fit with the machine's internal circuits, whereas high-level software uses human-like language and easy word phrases.
• Compilers translate the entire high-level program into machine language, making it more effective, whereas interpreters translate progressively, making it faster.
• Computers can't process information unless divided into digital signals, where its bits form the smallest info units.
• These bits represent 0 or 1 (on/off, yes/no) and form the basis for constructing more complex information.
• Bits are processed in groups, such as bytes, which represent 256 data items given that eight bits equal a byte.
• Computers operate using binary numbers representing all numbers using two digits, with rules similar to the decimal system.
• Computers automatically convert decimal numbers into binary and vice versa, with number processing invisible to the user.

Bits & Binary

• Codes that represent letters adapt words, phrases, and paragraphs to the binary circuits of computers.
• ASCII represents each character through seven bits, with an eighth specified via the code for info exchange.
• The three alternative number systems are binary, octal, and hexadecimal, binary being primarily used for internal calculations, and other systems used for external communication.
• The binary system uses two symbols, so that numbers need more digits in this system than in others.
• Binary system digits can have values of 0 or 1.
• To convert decimal numbers to binary numbers, the decimal is divided by two to write down the quotient and the remainder.
• If the quotient is more than one, it is divided by two continuously, writing the quotient and remainder until the quotient becomes 1.
• Binary is recorded as the last quotient, counting subsequent remainders from most recent to first.
• To transform binary to decimal, each binary digit is multiplied by raising two (the base) to a power.
• Two's power will depend on the digit; binary values are summed, listing powers from 1 to 20 with base 2.
• Units of measure allow measuring of capacity and inform transfer by adding to info per second.
• Basic units of measure includes: 1 bit and 1 byte.
• The byte number stores info and indicates characters (symbols, etc).
• Computer storage is measured in bytes.
• Multiple bytes are KB, MB, and TB.

Organization, Memory & CPU

• Major computer components consist of Central Processing Units (CPU), Arithmetic & Logic Unit (ALU), Control Unit, Main Memory (central), and Programs, a setup that was first proposed by physicist Jon Von Newman.
• The physical medium of data transmission between the CPU, memory, and I/O devices is the bus.
• Buses are sets of parallel conducting links transferring binary information across devices.
• Buses have address direction to identify device cells in the memory, data buses, and the control buses, which signal access or write.
• Primary memory stores executing program instructions and data, and is volatile, clearing its content when there's no power.
• With primary memory, a program must load into the memory to be executed.
• Addressing uses the Register of Directions (RDM) and the Register of Memory Exchange (RIM).
• CPU is the most important component in a computer, extracting instructions; and units such as registers allow for internal processing.
• ALU performs math operations and calculations.
• Control units search memory.
• I/O (Input/Output) devices are important interfaces of the computer with its peripherals.
• Motherboards serve as the main circuit board with auxiliary and central connecting functionality.

Processors & Internal Hardware

• CPUs are integrated by transistors, diodes, and resistors, and execute primary functions, like data processing, in binary.
• Their speeds are rated with Hz, which indicate how fast the processing is.
• The cache is used to run programs in their fastest and most fluid speeds.
• SDRAM allows fast access to storage.
• The processors have a cooler to deal with heat.
• The processor connects memory and components via a BUS to control communication.
• 32-bit and 64-bit are the main types of processors that help with improving speed and output, that will then be able to work in separate channels for multiple units of information.
• Dual-core (2+ physical cores) CPUs are two processors in the space of one.
• Operating systems will communicate with the model and specs of the processor, through certain menus like system-checking components.
• Memory speeds depend on costs; the information is distributed to different memories with other physical traits.
• Internal memory stores CPU registries at high-speeds.
• The CPU processes data with BUS-connected parts.
• Secondary memory is slow and used for large files.
• Units of storage is listed with all units, such as bits and bytes (1024).

Memory & Flash

• Memories are listed with access types and mediums, such as semi-conductors and magnetics.
• RAM- It loads instructions executed by other units, which is done randomly.
• SRAM can sustain data when activated with no refresh.
• DRAM's main attribute is a high-density structure that is still operable with quickness; they sustain high bit positions.
• Cache memory is a common high-speed system, the fastest that the computer uses to prevent accessing DRAM.
• ROM is a read-only memory that maintains stored values despite the turning on/off.
• In ROM, programming is not easily modified, providing safety.
• The ROM contains a BIOS program.
• Subdivisions are based programming style: ROM, PROM, EPROM.
• FLASH is programmable by users, and the erasing is done quickly.
• Sequential memory accesses depend of the location of the word.
• Registers, columns, and FIFOs are the common divisions.

ROM & BIOS

• BIOS (Basic Input/Output System) has hardware with software.
• The software recognizes devices in RAM, enabling the software to be installed.
• It controls the OS.
• It also contains a POST for commands.
• Setup houses basic config parameters.
• POST can test all the systems.
• Setup controls settings.

External Connections

• Power, performance and security features all vary, but can be reconfigured by the user; saving the changes records the information on the OS.
• Ports are communicative channels which data passes through; external ports are connectors to devices.
• Parallel ports transfer at high rates.
• Serial lines send with one direction at a time.
• Ports are Mini-Din, USB.
• Multimedia includes sounds via audio devices or speakers.
• Video options are VGA, DVI, and HDMI.
• Audio ports include headphones and devices.

Peripheral Devices & Backups

• Peripheral devices are auxiliary with unified processing with the OS.
• These peripherals have 5 main types: input (cams), output (speakers), I/O devices (headphones), memory, and communication.
• Backups is a safety copy to recover from data loss, or damage, with access to external elements like hard and flash-drives.