NIMCET 2021 — Computer PYQ
NIMCET | Computer | 2021To fetch data from the secondary memory which one of the following register is used?
Choose the correct answer:
- A. MAR(Correct Answer)
- B. PC
- C. IR
- D. MBR
Explanation
Solution
Step 1: Understanding Register Roles Registers are small, high-speed storage locations inside the CPU. To interact with any memory (Primary or through I/O controllers for Secondary storage), specific registers are required to handle addresses and data.
Step 2: Analysis of the Registers
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MAR (Memory Address Register): This register holds the memory address of the data or instruction that needs to be accessed (read from or written to). When the CPU needs to fetch data, it places the specific address into the MAR.
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MBR (Memory Buffer Register): Also known as the Memory Data Register (MDR), it holds the actual data being transferred to or from the memory.
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IR (Instruction Register): It holds the instruction currently being executed by the CPU.
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PC (Program Counter): It holds the address of the next instruction to be fetched and executed.
Step 3: The Fetch Process To initiate a fetch operation, the CPU must first identify where the data is located. It sends the location's address to the MAR, which then communicates with the memory bus to retrieve the information.
Final Answer: The register used to fetch data by specifying its location is the MAR (Memory Address Register).

