This is Short Discriptio
The instruction cycle (or fetch-decode-execute cycle) is the fundamental operational process of a computer's CPU, where it continuously fetches, decodes, and executes machine-level instructions in a loop from boot-up to shutdown. It ensures orderly processing, allowing the CPU to perform tasks by repeating these steps millions of times per second.
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Key Stages of the Instruction Cycle:
Fetch: The CPU retrieves the next instruction from memory, based on the address stored in the Program Counter (PC).
Decode: The Control Unit (CU) interprets the instruction to determine which operation is required.
Execute: The CPU performs the required action, such as an arithmetic operation by the ALU, data transfer, or logical operation.
Store/Write Back: The result of the execution is written back to memory or a register if necessary.
Update Program Counter: The PC is updated to point to the next instruction.
Components Involved:
Program Counter (PC): Tracks the address of the next instruction.
Instruction Register (IR): Holds the current instruction being executed.
Memory Address Register (MAR): Holds the memory address being accessed.
Memory Data Register (MDR): Holds data fetched from or waiting to be written to memory.
Control Unit (CU): Directs the operation of the processor.
Arithmetic Logic Unit (ALU): Performs calculations and logical operations.
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This cycle ensures that instructions are processed in a clear, ordered, and efficient manner.