COMPUTER SCIENCE AND ENGINEERING
COMPUTER ARCHITECTURE
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Fetches
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Decodes
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Executes
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Runs
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Detailed explanation-1: -The purpose of the CPU is to process data. The CPU works by following a process known as ‘fetch, decode and execute’. The CPU fetches an instruction from memory, decodes this instruction and then executes it. The CPU carries out this cycle continuously, millions of times per second.
Detailed explanation-2: -Eventually, the instruction in the MDR is copied into the current instruction register (CIR) which acts as a temporary holding ground for the instruction that has just been fetched from memory. During the decode stage, the control unit (CU) will decode the instruction in the CIR.
Detailed explanation-3: -In the decode part of the cycle, the control unit works out what the instruction is and sends signals to coordinate the other components. Lastly, during the execute part of the cycle, the instruction is executed, using the ALU if necessary.
Detailed explanation-4: -It fetches the instructions from the main memory and executes them. This is done repeatedly from when the computer is booted up to when it is shut down. The CPU fetches the instructions one at a time from the main memory into the registers.