3.4 Computer SystemsMedium Exam FrequencyOCR

MAR, MDR & Registers

Revise MAR, MDR & Registers in 3.4 Computer Systems for GCSE Computer Science with 15 exam-style questions and 10 flashcards. This topic appears regularly enough that it should be part of a solid GCSE revision cycle.

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The Library Search

Introduction 2

CPU Registers Detail

Diagram 3

Deep Dive: How MAR and MDR Work Together

Deep Dive 4

MAR - Memory Address Register

Key Facts 5

MDR - Memory Data Register

Key Facts 6

MAR vs MDR - Quick Comparison

Key Facts 7

Exam Tips - MAR and MDR

Exam Tips 8

Knowledge Organiser: MAR and MDR Registers

Summary

Sample Flashcards

What does MAR hold?

The address of data to be read/written (WHERE)

What does MDR hold?

The actual data being transferred (WHAT)

Exam questions for MAR, MDR & Registers

What does MAR stand for?

A. Memory Access Register
B. Memory Address Register
C. Memory Arithmetic Register
D. Main Address Register

1 markfoundation

Explain the difference between the MAR and the MDR.

2 marksstandard

exam-style questions

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