Unit 3: Hardware - Computer Architecture

Computer Architecture and the Central Processing Unit

• Unit Context: Hardware (Unit 3)
• Date of Record: Feb 17, 2024
• Central Processing Unit (CPU):
  • The CPU of the computer is dedicated to processing instructions and data.
  • Responsible for carrying out the complete fetch-decode-execute (FDE) cycle.
• Microprocessor:
  • Defined as a specific type of integrated circuit constructed on a single chip.

Essential Processing Units

• Units Definition:
  • Essential internal components within a computer engineered to perform specific tasks.
• Arithmetic Logic Unit (ALU):
  • Executes instructions.
  • Performs arithmetic calculations and logical operations.
  • Stores interim results of ongoing calculations.
• Control Unit (CU):
  • Decodes instructions.
  • Directs and coordinates the relevant parts and operations of the processor.

Dedicated CPU Registers

• General Purpose of Registers:
  • High-speed storage locations that temporarily hold data, instructions, and addresses.
  • Provide immediate access to necessary operational data during the fetch-decode-execute (FDE) cycle.
• Program Counter (PC):
  • Stores the address of the next instruction to be fetched and executed.
• Memory Address Register (MAR):
  • Stores the memory address of the next instruction or data word to be fetched from memory.
• Memory Data Register (MDR):
  • Stores the actual data passed to or fetched from the memory address held in the MAR.
• Current Instruction Register (CIR):
  • Stores the instruction that is currently being executed.
• Accumulator (ACC):
  • Stores the direct result of each calculation performed by the Arithmetic Logic Unit.