Learn: MDR - Storing the Data

Welcome!You've already learned about the MAR and how the CPU stores memory addresses. Now, let's build on that by exploring the MDR, which stores the actual data being processed.

What is the MDR?The Memory Data Register (MDR) is a key register in the CPU. It temporarily holds the data that is being transferred to or from memory. This data could be instructions for the CPU or information needed for calculations.

Why is the MDR important?The MDR works closely with the MAR. While the MAR stores the memory address, the MDR stores the actual data at that address or incoming data from memory. This ensures the CPU can process data efficiently and accurately.

How does the MDR work?When the CPU accesses memory, the MAR stores the address of the required data. The MDR then stores the data fetched from that address or prepares data to be written to memory. This process is part of the fetch-execute cycle.

MAR and MDRWorking together, the MAR and MDR allow the CPU to communicate with memory. The MAR sends the address of the required data, and the MDR handles the actual data moving to or from the CPU.

Review Time!Great work! You've learned about the MDR and how it stores data during CPU operations. Let's test your understanding with a few more questions.