Midterm 2 Review

Tom Kelliher, CS 240

Apr. 12, 1999

Administrivia

Review

• Note well: The exam covers 5.1--5.4. This review should not be construed as limiting the scope of the exam. You are responsible for all material.

• The exam is closed book. Appropriate charts will be provided.

• Structure of the exam and types of questions.

1. Instruction formats and fields. Placement, usage.

2. Instruction cycle. Machine/clock cycle.

3. The abstract datapath.

4. The instructions under consideration: 5 R-format, lw/sw, beq.

   Instruction mixes and weighted averages.

   Adding instructions.

5. Datapath components: registers, register file, ALU, memory, misc.

   Functional units. I.e., fetch unit, branch unit. Reconciling.

6. Fitting the clock cycle to the datapath.

7. Datapath control signals.

8. Comparison of the two implementations.

9. The abstract datapath for the multicycle implementation.

   Rationales for the additional registers.

10. The multicycle datapath.

    Control signals.

11. Multicycle implementation state machine.

    High level view.

    Derived directly from operations. Example: lw. States merged when advantageous.