Architecture of the CPU

basic model of a computer system

What is Von Neumann architecture?

The idea of holding both programs and data in memory

Central Processing Unit (CPU)

hardware that executes programs and manages the rest of the hardware

Cache

very fast memory

What does the processor do to run the program?

Fetch

What does the control unit do?

• Controls the execution of instructions in the correct sequence
• Decodes instructions
• Regulates and controls processor timings using regular pulses from the system clock
• Sends and receives control signals to and from other devices within the computer

Arithematic Logic Unit (ALU)

• Logic operations (AND

Types of registers

MAR

What does the MAR do?

Memory Address Register - holds the address of the instruction or piece of data to be fetched or stored

What does the MDR do?

Memory Data Register - holds the data or a program instruction temporarily when it is fetched from memory or is to be sent to memory

What does the PC do?

Program Counter - holds the memory address of the next instruction to be processed

What does the ACC do?

Holds the results of calculations from the ALU

What are the main factors affecting CPU?

• Clock speed
• Cache size
• Number of cores