CS 154 Midterm Review

Prof. Fred Chong
Department of Computer Science
University of California at Santa Barbara


DISCLAIMER: This review sheet is not guaranteed to be all-inclusive, but I will attempt to cover the majority of important topics in this list.

You will need your Matloff handout . The exam is open book and open notes. A calculator may be helpful to you and you may bring one.


Old exams from previous classes and other faculty are available, but are not necessarily representative of the exam.

NOTE: The old exam solutions occasionally contain errors. It is your responsibility to understand and verify the solutions. Applying an error from an old exam to your exam will not get you credit.

In general, you should be prepared to understand a new machine similar to the MIC-1 and answer questions relating to the following topics as they pertain to the new machine. Understanding labs 1-2 is the best preparation.


MIC-1 Microprogramming

  • Make sure you understand the dispatch code. Why "tir:=lshift(ir+ir)" on line 3 of the MIC-1 implementation of the MAC-1?
  • Make sure you understand what happens in each of the four subcycles.
  • Understand why certain operations can not be done in the same instruction (cycle). Why can't we do "a:=b; c:=d;" in one cycle? Why can't we do "mar:=d; a:=b+c;" in one cycle?

    Pipelining

  • Understand how pipelining is applied to an architecture. What determines clock cycle? Why not use an arbitrarily large number of stages? Know how to calculate throughput and latency for a pipeline. How does latch overhead (pipeline registers) affect these calculations?
  • Understand what state is persistent in a processor and what makes a nop.

    Last updated May 2009
    chong@cs.ucsb.edu