computer architecture flashcard

Definition of CPU

brain of the computer

How does the CPU communicate with memory

The CPU communicates with memory through the system bus

What are those three busses

Address bus,Data bus and control bus

Definition of address bus

Carries memory addresse

Definition of control bus

Carries control and timing signals

Definition of data bus

Transfers data between components

What is the difference between RISC and CISC architectures

The main difference between RISC and CISC architectures is how instructions are designed and executed.

RISC (Reduced Instruction Set Computer)

• Uses a small, simple set of instructions

• Instructions usually execute in one clock cycle

• Focuses on speed and efficiency

• Uses more registers

• Easier to pipeline

• Example processors: ARM, MIPS

CISC (Complex Instruction Set Computer)

• Uses a large, complex set of instructions

• Instructions may take multiple clock cycles

• Designed to reduce the number of instructions per program

• Uses fewer registers

• More complex hardware

• Example processors: Intel x86

What is the fetch–decode–execute cycle?

1. Fetch

• The CPU retrieves an instruction from main memory (RAM)

• The instruction is stored in the Instruction Register (IR)

• The Program Counter (PC) points to the address of the next instruction

2. Decode

• The Control Unit interprets the instruction

• It determines what operation to perform and which data is needed

3. Execute

• The CPU carries out the instruction

• The ALU performs calculations or logic operations

• Data may be written back to memory or registers