Unit 324 Stuff I Should Remember Flashcards
What are the Dedicated Registers? (5)
- Program Counter (PC)-
- Current Instructions Register (CIR)
- Memory Address Register (MAR)
- Memory Data Register (MDR)
- Accumulator
What is the Fetch section of the FDE Cycle? (4)
- The address of the next instruction is copied from the PC to the Memory Address Register
- The instruction held at that address is copied to the Memory Data Register
- Simultaneously, the contents of the Program Counter (PC) are incremented
- The contents of the MDR are copied to the current Instruction Register
What is Parallel Processing?
Using several processor cores working at the same time is known as parallel or concurrent processing
What is Pipelining?
Improves performance by overlapping stages in the FDE cycle or by breaking down the stages in an arithmetic instructions
What happens in Von Neumann Architecture?
Instructions and data are stored in a common main memory and transferred using a single shared bus
What happens in Harvard Architecture?
A
Data and instructions are separated into separate memories using different buses
Q
How is Von Neumann and Harvard Architecture used in Desktop Computers?
There is one main memory for holding both data and instructions, but cache memory is divided into an instruction cache and a data cache so data and instructions are retrieved using Harvard architecture
What is CISC?
Complex Instruction Set Computers
A large instruction set is used to accomplish tasks in as few lines of assembly language as possible
What is RISC?
Reduced Instruction Set Computers
A minimum number of very simple instructions, each taking one clock cycle, are used to accomplish all the required operations in multiple general purpose registers
What is a GPU?
Graphics Processing Unit
A specialized electronic circuit which is very efficient at manipulating computer graphics and image processing
What are the features of a Hard Disk? (3)
- High capacity
- Relatively cheap storage per TB
- Fast read and write speeds
What are the features of Solid State? (6)
- Durable
- Less capacity than Hard Disk
- Faster than Hard Disk
- More portable
- Consumes less power
- More expensive than Hard Disk
What are the features of a USB? (4)
- Can store up to 128GB
- Cheap
- Can be password protected
- Useful for transferring data between computers
What functions does the OS provide? (4)
- User interface
- Memory management
- Interrupt handling
- Processor scheduling
What is Paging?
Available memory is divided into fixed chunks(pages). Each page has an address. Each running program in RAM is given sufficient pages but pages may not be contiguous
What is Segmentation?
Memory is divided into segments that can be different lengths. A particular function or subroutine occupies each segment
What is BIOS?
Basic Input Output System
Boots the computer at start-up. Stored in ROM
What is a Device Driver?
A program that provides an interface for the OS to interact with a device. Drivers are hardware dependent and OS specific
What is a Virtual Machine?
A compute resource that uses software instead of a physical computer to run programs and deploy apps
What are the different types of System Software? (4)
- Operating System
- Utilities
- Libraries
- Translators
What are the categories of Application Software? (3)
- General purpose
- Special purpose
- Bespoke
What is the difference between Off-The-Shelf Software and Bespoke Software?
Off-the-shelf software is ready made software available for anyone to purchase. Bespoke software is custom made
What criteria might you use when selecting an application to use? (5)
- Functionality
- Hardware
- Cost
- Availability
- Reliability
What are the features of a Compiler? (4)
- Programs can be run many times without needing compiling again
- Faster to execute
- Executable code does not require an interpreter to run
- Compiled code can not be easily read and copied by others
What are the features of an Interpreter? (2)
- Source code can be run on any machine with an interpreter
- If an error is found, code does not need to be fully compiled
What are the 5 five stages of Compilation?
-Lexical analysis - All unnecessary spaces and all comments removed. Keywords are replaced with tokens
- Symbol table - Symbol table with tokens is built up. Keeps track of the run-time memory address for each identifier
- Syntax analysis - The stream of tokens is split up into phrases. Each phrase is parsed. If the phrase isn’t valid, an error will be recorded
- Semantic analysis - The code is checked for errors that are logical not syntax
- Code generation - The compiler generates the machine code