9. CISC (Complex Instruction Set Computer) Architecture

3. CISC (Complex Instruction Set Computer) Architecture

CISC systems have a large set of instructions that perform complex tasks in fewer lines of code.

Key Features:

  • Single instructions can perform multiple low-level operations.
  • Instructions take varying amounts of time to execute.
  • Used in Intel x86 processors and older mainframes.

Advantages:

✔ Requires less memory for complex programs.
✔ Simplifies compiler design.

Disadvantages:

✖ More complex hardware design.
✖ Slower execution due to complex instruction decoding.

4. RISC (Reduced Instruction Set Computer) Architecture

RISC architecture simplifies the instruction set, allowing for faster execution.

Key Features:

  • Uses a small set of simple instructions.
  • Instructions are executed in a single clock cycle.
  • Used in ARM processors, modern mobile devices, and gaming consoles.

Advantages:

✔ Faster execution speed.
✔ Simplified hardware design.

Disadvantages:

✖ Requires more memory for program execution.
✖ More dependency on compiler optimization.