Computer Sytems and CPU Flashcards
Explain what a computer is
An electronic device that takes an input, processes data and delivers an output.
Name 2 examples of input devices
controller
keyboard
mouse
Name 2 examples of output devices
speaker
screen
projector
Name 2 examples of storage devices
CD
hard drive
floppy disk
What does a computer system consist of?
+what do they do?
hardware and software that works together to process data/complete tas
What are embedded systems?
computers built into other devices, usually dedicated systems
What does CPU stand for?
Central processing unit
What does the CPU do?
Processes all of the data and instructions that make the system work
What are the 3 main parts of the CPU?
Control Unit (CU)
Arithmetic Logic Unit (ALU)
Cache
What does the CPU do/follow?
The Fetch-Execute cycle / Fetch-Decode-Execute cycle
What happens in the fetch instruction stage?
1) Copies memory address from the program counter to the MAR
2) Copies the instruction stored in the MAR address to the MDR
3) The address in the program counter is incremented to point to the address of the next cycle
What happens in the decode instruction stage?
1) Instruction is decoded by the CU, it then after may prepare for the next step
What happens in the execute instruction stage?
1) What happens during the execute stage depends on the instuction, for example:
– load data from memory
– do a calculation or logic operation
– change address in the PC
2) The process than repeats
John Von Neumann’s CPU architecture
What does PC stand for?
Program Counter
John Von Neumann’s CPU architecture
What does MAR stand for?
Memory Address Register
