1.1.2-3 System Architecture Flashcards
What is the fetch-decode-execute cycle?
1.Fetches instructions
2.Decodes them
3.Carries out the the instructions
Fetch
Processor fetches the instructions from memory and uses the program counter to keep track of where it is
Decode
Once the instruction is loaded, the CPU needs to know what it means, so the instruction is decoded
Execute
The instruction is then carried out (calculations or transfer data)
Clock speed
Rate at which instructions are processed by CPU (3GHz = Billion cycles per second)
Cache size
Allows temporarily stored data to be accessed very quickly.
What is L1 cache?
Used to store very frequently used data (small but fast)
What is L2 cache?
Slower and further away (still more efficient that main memory)
Why does the number of cores matter?
Each core can carry out separate tasks simultaneously.
What are the names of cores?
2 cores = dual core
4 cores = quadcore
6 cores = hexacore
8 cores = octacore
What is an embedded system?
Computer system programmed to a specific task within a larger device.
Examples of an embedded system?
Smartphone
Dishwasher
Navigation system
Micorwave
What are the characters of an embedded system?
Low power requirements
Low maintenance
Difficult to repair or replace