4.6 Fundamentals of Computer Systems Flashcards
Hardware
- Physical
- External or Internal
Barcode Reader
- Laser hits barcodes
- Light reflected off white
- Hits sensor, the converted
Digital Camera
- Light -> Lens -> Sensor
- Frequency = colour
- Sensor: grid of colours -> grid of binary
Laser Printer
- Electron -> -ve drum
- Creates pattern of +ve charges
- +ve charge -> ink -> paper
- Colours layer (4 colours: magenta, cyan, black, yellow)
- Heat press
RFID Reader
- Data as radio waves -> chip
- Activates energy, chip modulates energy
- Info converted -> stored/compared to database
Software
Non-Physical
Application Software
- Specific purpose for user’s task
- Bespoke = 1 specific user
- Word Processing, Games, Spreadsheets, Browsers
System Software
- Controls the computer
- Runs hardware + application software
- OS, Utility, Libraries, Translators
Utilities
Disk Defragmenters
File Managers
Anti-Virus
Compression
Back Up
The Operating System
Controls and organises general operation of computer
Managing Memory (loading programs, virtual memory(
Handling External Peripherals (device drivers)
Security (log in)
User Interface (WIMP)
(Managing the Processor)
(Networking)
(Utility Programs)
(- file manager)
(- anti virus)
(- encryption)
(- installers)
Low Level Languages
1 line of code = 1 instruction
Close to Hardware
Machine code/Assembly Language
Machine Code
1st Generation
Binary/Hex Instructions
Most direct language
Assembly Language
2nd Generation
mnemonic code -> machine code
High Level Languages
1 line of code = many instructions
Human
3rd = Java
4th = Python
Imperative High- Level Languages
Uses sequence, selection, iteration
Executed in order
Procedural language
Subroutines, Procedures
