Learn: What Registers Do (Big Picture)

Welcome!Welcome back! You've already learned about why the CPU is essential and the fetch-decode-execute cycle. Today, we'll explore what registers do and their importance in the CPU.

What Are Registers?Registers are small, fast storage locations within the CPU. They temporarily hold data and instructions during processing. Registers are essential because they make the CPU operations faster by keeping critical data close to the processor.

Program Counter (PC)The Program Counter keeps track of the memory address of the next instruction to be executed. It ensures the CPU processes instructions in the correct order during the fetch-decode-execute cycle.

Memory Address Register (MAR)The Memory Address Register holds the address in memory where data or instructions are located. It works with the Program Counter to fetch data and instructions from memory.

Memory Data Register (MDR)The Memory Data Register temporarily holds the actual data or instruction fetched from memory or ready to be written to memory. It acts as a bridge between the CPU and RAM.

AccumulatorThe Accumulator is used for temporary storage of results from arithmetic and logic operations. It allows calculations to proceed efficiently during the execute phase of the cycle.

How Registers Work TogetherRegisters like the PC, MAR, MDR, and Accumulator work together during the fetch-decode-execute cycle to process instructions. They ensure the CPU can efficiently fetch, store, and execute data.

Review Time!Great work! You've learned about the key registers in the CPU and their roles. Let's review everything we've covered so far.