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Computer Science Chapter 1 - Coggle Diagram
Computer Science Chapter 1
Ways to Speed Up a CPU
Cache Size
When data is fetched or sent it is kept in the cache
It helps to avoid having to go to main memory for data / instructions because that takes more time
Is a temporary storage of memory from main memory
The more storage you can fit in the cache, the less you have to go all the way to main memory
Number of Cores
The cores contain the parts of a CPU e.g. the ALU
The more of these cores you have the more data you can simultaneously process
The number of cores is
basically
the number of copies of the CPU you have
Clock Speed
The number of instructions possible to fetch in a certain amount of time
The greater the clock speed the more instructions can be processed in a certain amount of time
Measured in hertz and cycles per second
Von Neumann Architecture
CPU
Stands for central processing unit, or processor
Designed to fetch and execute instructions
Components
Control unit: sends signals to control data movement in the CPU
Chache: fast access to frequently used data or instructions
Arithmetic logic unit (ALU): performs calculations and logical decisions
Clock: internal pulse at a constant rate to synchronize "fetch decode execute" cycle
Main Memory
Stores all data and instructions until it is needed by the CPU
Fixed and Stored Programs
Fixed Programs
Fixed computers have a single job with a single program
The program is not interchangeable with other programs
Stored Programs
Stored computers have several different interchangeable programs and can do multiple tasks
Von Neumann Structure
Information travels along bunches of wires called buses
Fetches information from main memory along buses
Control unit, ALU, clock, small amount of cache
"Fetch Decode Execute" Cycle
The instructions are
decoded
by the CPU so it knows what to do
The instruction is
executed
. This may involve the ALU and may involve data being sent / written to / from main memory
Instructions are
fetched
from main memory and sent to CPU along buses
Embedded Systems
Examples
Home appliances
Factory equipment
Traffic lights
Hospital equipment
Advantages
Small size
Small power consumption
Rugged operating ranges
Low cost
An embedded system is a system with a dedicated purpose, within another larger electrical system
Disadvantages
Limited processing resources
This makes them significantly more difficult to program and interact with