Lesson Plan

• Describe the purpose of registers and why a CPU needs them.
• Distinguish between general‑purpose and special‑purpose registers, providing at least two examples of each.
• Explain how registers participate in the fetch‑decode‑execute cycle.
• Analyse a simple data‑path diagram that involves both GPRs and SPRs.
• Compare the impact of GPRs versus SPRs on instruction‑set design.

• Projector and screen
• Whiteboard and markers
• Printed handout with register tables and a CPU diagram
• Slide deck covering GPRs and SPRs
• Worksheet with sample assembly instructions
• Laptops or computers with a simple CPU simulator/IDE

Begin with a quick analogy: “A CPU is like a busy kitchen where the chef needs ingredients right at hand.” Ask students what they already know about CPU components and set the success criteria – they will be able to name and explain the roles of different registers by the end of the lesson.

1. Do‑now (5') – short quiz on CPU components to activate prior knowledge.
2. Mini‑lecture (10') – purpose of registers, classification into GPRs and SPRs, using slides and examples.
3. Interactive diagram activity (12') – students label a CPU block diagram on the handout and discuss the flow of data.
4. Guided practice (10') – examine a sample assembly instruction, identify which registers are used and why.
5. Think‑pair‑share (8') – compare how GPRs and SPRs influence instruction‑set design; groups present findings.
6. Check for understanding (5') – exit‑ticket question: “Name one GPR and one SPR and state their primary function.”

Recap the key differences between general‑purpose and special‑purpose registers and how they fit into the CPU data path. Collect the exit tickets to gauge understanding, and assign a brief homework: students create a table of three additional registers (one GPR, two SPRs) with their functions.