CS 110 Homework Assignment 3
Due: Friday 19 October, 9PM

  1. Points 3, S&G, 2.5, pg 46
    Which of the following instructions should be privileged?
    1. Set value of timer
    2. Read the clock
    3. Clear memory
    4. Turn Off Interrupts
    5. Switch from user to monitor mode
  2. Points 3, S&G, 2.7, pg 46
    Some early computers protected the operating system by placing it in a memory partition that could not be modified by either the user job or the operating system itself. Describe two difficulties that you think could arise with such a scheme.
  3. Points 6, 2-1 from Paul with the following changes:
    write only a version with all appropriate nops
  4. Points 6, 2-3 from Paul with the following changes:
    write only a version with all appropriate nops

Notes:

Where to Turn in:

The plastic bins outside Mike's office, 249 Olin.

Last modified Oct 15, 01 by mike@cs.hmc.edu