Computer Systems Flashcards
What is a translator?
It translates from one language to another.
What are the three types of translators?
Compiler, Interpreter, Assembler
What is the purpose of the CPU?
Processes instructions that drive the computer.
What is Von Neumann architecture?
The program and data are both stored in the same memory. This allows instructions to be fetched and executed sequentially.
What are the main components of the CPU?
ALU (arithmetic logic unit)
Clock
Control Unit
Bus
Registers
What is the purpose of the ALU?
Performs arithmetic and logic operations, and shifts bits in a computer word.
What is the purpose of the clock?
The clock controls the timings of the processor, and switches between 0 and 1 several million times a second.
This is measured in hertz Hz.
What are registers?
Registers are very high speed memory locations in the CPU. An 8-bit CPU will have registers that are each 8-bit.
What is hardware?
The physical components that make up a computer.
What is software?
The non-physical programs that are stored by and run on a computer.
What is system software?
Software that provides a platform for other software to run.
What is machine code?
Code written in binary to execute an instruction.
What is assembly code?
Assembly code allows a programmer to write programs more easily.
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Can a machine or assembly code written on a Mac be run on a Windows computer?
No - the low level languages are processor specific.
What is assembly language used for?
Embedded systems
Controls precisely any instruction on the processor
Controls specific hardware components.
What type of language are assembly and machine code?
Low-level language.
What are the advantages of high-level languages?
Easier to debug and read
Easier to learn as they look a lot more like English
Can be run on different types of processors
Programs are written faster.
What are the advantages of low-level languages?
More control over hardware
Run much quicker
Require less RAM
What is an assembler?
Translates assembly code into machine code.
What is a compiler?
Translates a whole high-level language program into machine code at once and produces an object code.
What languages are high-level languages?
Python, Java, C#, Visual Basic, C++, Javascript
What is an interpreter?
Interpreter translates each line of a high-level program separately and stops if there is an error to display an error message.
What languages use compilers?
C, C++
What is the purpose of the Control Unit?
Co-ordinates and controls the instructions taking place in the CPU.
Decodes and executes instructions.
Receives instructions from clock.
Define the term ‘bus’.
A set of parallel wires that carry instructions and data from one component in the CPU to another.
What is the purpose of the address bus?
Sends the memory location, or address, of the memory location that the CPU wants to access.
What is the purpose of the data bus?
Sends the data that is being worked on in a specific address to the CPU.
What is the purpose of the control bus?
Sends the control signals.
What is the cycle called that the CPU is constantly working on?
Fetch-Decode-Execute Cycle.
What is cache?
A small amount of very fast, expensive memory that is stored near the CPU. It is slightly slower than registers but faster than main memory (RAM).
What is stored in cache?
Data or instructions that are used frequently are temporarily stored in cache in case they are used again.
Define the term ‘volatile’.
If a data store is volatile, it means that if the computer’s power is switched off then all of the data in that data store is lost.
What type of data stores are volatile and non-volatile?
RAM is volatile
ROM is non-volatile
Secondary storage is non-volatile.
What does RAM stand for?
Random Access Memory
What does ROM stand for?
Read only memory
What does memory speed refer to?
The speed that the memory location can be accessed.
What is stored in RAM?
The operating system
The software in use
The data the software is using
Why is RAM named as it is?
The ability of the CPU to access any part of the memory in the same amount of time.
What is stored in ROM?
Instructions and data that are necessary for the computer to run are stored in ROM, as it is Read-Only, so the instructions can not be changed, and it is non-volatile so they are stored permanently.
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How do the number of cores in a CPU affect the performance of a computer?
The more cores there are, generally more instructions can be processed per second.
Example:
4 x 2.4 GHz cores is better than 2 x 2.4 GHz because twice as many instructions can THEORETICALLY be processed per second.
What is BIOS and what does it stand for?
BIOS is Basic Input/Output System and runs whenever the computer is run and it checks if all the hardware is running properly.
What is a bootstrap loader?
A bootstrap loader is software that is stored in the ROM, that loads the operating system.
