CPU registers diagram showing the Memory Address Register (MAR) connected to the Address Bus, and Memory Data Register (MDR) connected to the Data Bus, with Program Counter and Accumulator also shown

This diagram covers CPU Registers Detail within MAR, MDR & Registers for GCSE Computer Science. 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 still be part of a steady revision cycle. It is section 2 of 8 in this topic. Focus on the labels, the relationships between parts, and the explanation that turns the diagram into an exam-ready answer.

Practice 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

Quick recall flashcards

What does MDR hold?

The actual data being transferred (WHAT)

What does MAR hold?

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

The Library Search

Deep Dive: How MAR and MDR Work Together

CPU Registers Detail

Practice questions for MAR, MDR & Registers

Quick recall flashcards

15 questions on MAR, MDR & Registers: practise free