Components of a Computer System Flashcards
What is a computer?
A machine that processes data
What is a embedded system?
Computers built into other devices
What is hardware?
Physical stuff that makes your computer system
What is software?
The programs or applications that a computer systems runs
What are the 2 types of computers and what do they do?
- General Purpose - designed to perform many tasks
- Dedicated System - designed for one particular function
What does the CPU do?
Processes all the data and instructions that make the system work
What effects the processing power of the CPU?
- Clock speed
- Number of cores
- Cache size
What does the Control Unit do?
- Manges fetch decode execution cycle
- Controls flow of data inside and out side CPU
What does the Arithmetic Logic Unit do?
- Does all the calculations
- Performs logic operations and binary shifts
What does the Cache do?
- Very fast memory in the CPU
- Stores regular used data so the CPU can access quickly
- Very low capacity
What type of cache levels are there?
L1 - Quickest, lowest capacity
L2 - Slower than L1 but can hold more
L3 - Slower than L2 but can hold more
What do registers do in the CPU?
- Temporarily hold tiny bits of data needed by CPU
- Super quick to read/write
What does the program counter do in the CU?
Holds memory address of the instructions of each cycle
What does the accumulator do in the CU?
Stores intermediate results of calculations in the ALU
What is does the MAR do in the CU?
Holds any memory address about to be used by the CPU. Address might point to data or a CPU instruction
What is does the MDR do in the CU?
Holds actual data or instruction. May have been fetched from memory or waiting to be written to memory
What does the fetch instruction do in the “Fetch-Decode-Execute” cycle?
- Copy memory address from program counter to the MAR
- Copy instructions stored in MAR to MDR
What does the decode instruction do in the “Fetch-Decode-Execute” cycle?
- Instructions in MDR is decoded by CU
- CU then prepares for next step
What does the execute instruction do in the “Fetch-Decode-Execute” cycle?
- Instruction is performed
What is volatile memory?
Temporary memory; needs power to retain data
What is non-volatile memory?
Permanent memory - it keeps content with no power
What does RAM store?
It stores all the data, files and programs that are currently being used
How does virtual memory work?
- When RAM full, data that is not often used moved here
- If data needs to be read, it moves back into RAM
What are the cons of virtual memory?
- Slow to transfer back to RAM
- Can make computer slow when switching through applications
