1.1 Fundamentals of computer systems Flashcards
What is the CPU
Central Processing Unit
In charge of the operation and functioning of the computer, carrying out all processing
What is the ALU
Arithmetic Logic Unit
Performs calculations on the data given to it
What is the purpose of the Control Unit
Moves the data and checks that everything moves at the same time
Name the 5 registers
Program Counter MAR - Memory Address Register MDR - Memory Data Register CIR - Current Instruction Register ACC - Accuulator
Discuss the function of each register
PC - Points to the address of the next instruction to be fetched
MAR - stores the address of the memory location being accessed
MDR - stores the data that is about to be read from memory
CIR - splits the data into the opcode or the operand
Accumulator - stores the result of the calculations made by the ALU
Name the 3 buses
Data
Control
Address
Discuss the function of each bus
Data bus - carries the data between registers
Control bus - control the flow of data through the CPU
Address bus - transfers the address from the MAR
Outline factors affecting the CPU’s performance
Clock speed - The more clock cycles that the CPU can perform the more FDE cycles that can be performed
Multiple cores - as each core has its own cache, this makes the processing slightly faster, allows for multi-tasking, all cores can work on the same problem
Cache size - quicker than accessing RAM
Other factors include; pipelining, GPU’s, bandwidth of the buses and size of the registers
Describe the Von Neumann Architecture
Data and instructions are stored in the same place in memory
Next instruction cannot be fetched while another process is being carried out which slows the processor down
Both sent along the data bus
Uses a single control unit
Control unit is separate to the ALU
Describe the Harvard Architecture
Data and instructions are stored in separate memory locations
More than one data bus
Can make use of pipelining
Used by RISC processors
What is pipelining?
Data and processes are arranged in a series where the output of one is the input of the next
Improves the efficiency of a processor when using the Harvard Architecture
When one instruction is being fetched, the next can be decoded
What is parallel processing?
Running multiple processes at the same time. Can be implemented through:
Multiple Cores
Distributed Computing
Discuss the differences between RISC and CISC
RISC - Simpler instructions, takes longer/more instructions to complete a task, used in phones, pipelinign is supported, cheaper, uniform instruction formatting meaning easier decoding, same sized registers meaing a simpler complier design
CISC - Complex instructions, less instructions needed to complete a task, used in desktop computers, complex hardware meaning it is expensive, harder decoding due to non-uniform format, different sized registers - complex compiler design
What are GPU’s and what is their purpose?
Graphical Processing Unit
Originally designed to handle graphics
Includes thousands of simpler more efficient cores than a standarad CPU
Performs simple instructions on a large data set
Can run parallel processing
Can be useful for machine learning and breaking passwords
Define and give examples of an input device
A device used to enter data into a computer system
Microphone, Camera, Keyboard, Mouse
