Central Processing Unit (CPU) - SS2 ICT Past Questions and Answers - page 2

The Arithmetic and Logic Unit (ALU) is responsible for performing mathematical calculations (arithmetic operations) and logical operations on binary data. It receives inputs from registers, processes the data based on the instructions received from the Control Unit, and produces outputs that are either stored back in registers or sent to memory. The ALU performs addition, subtraction, multiplication, division, AND, OR, NOT, and other basic operations using binary logic.

The Control Unit manages the instruction execution process by fetching instructions from memory, decoding them to understand the required operation, and then generating control signals to coordinate the activities of various components. It uses a clock signal to synchronize the timing of these activities. Each instruction's execution is broken down into micro-steps, and the Control Unit ensures that these micro-steps occur in the correct sequence. It also manages branching and conditional execution, ensuring that the correct paths are taken based on program logic.

The Control Unit acts as the coordinator of the CPU's activities. It interacts closely with other components like the Arithmetic and Logic Unit (ALU), registers, and memory. The Control Unit fetches instructions from memory and decodes them to determine what operation to perform. It then sends control signals to the ALU to perform calculations and to other parts of the CPU to move data between registers, memory, and other components. In essence, the Control Unit ensures that all components work harmoniously to execute the instructions correctly.

The ALU operates on binary data by using the principles of Boolean logic. It uses electronic circuits to perform addition, subtraction, and other arithmetic operations by manipulating binary digits (0s and 1s). For logical operations like AND, OR, and NOT, the ALU compares corresponding bits in the input data and produces the desired output based on the logical rules. The ALU's circuits and components are designed to handle these operations at the electronic level, converting binary data into the desired results.

The CPU plays a pivotal role in a computer's operation by executing instructions from programs. It performs calculations, processes data, manages memory, and controls input/output operations. The CPU's components, including the ALU and Control Unit, collectively process information, allowing the computer to perform tasks ranging from basic arithmetic operations to complex computations. Its speed, architecture, and capabilities significantly influence a computer's performance and its ability to handle various software applications efficiently.