Computer Science 471

*Due by 5 PM, Monday Sept. 23, 1996*

**1.** (5 points) Make gates out of muxes. Show how to use a single
2-input multiplexor to implement AND, OR, NOT, and EXOR gates (i.e., one mux
per gate).
Assume that logical values 0 and 1 are available, and that your two inputs
are presented in high-true form only. One of these gates should
give you trouble; please explain.

**2.** (5 points) Problem 3.11 from the text.

**3.** (5 points) Problems 3.12 through 3.15 from the text.

**4.** (5 points) What hardware is required to test 32-bit quantities
for equality? Draw a gate-level circuit with 32-bit
inputs *x* and *y*,
and 1-bit output *x=y*. Use some clear shorthand for
repeated instances of the same structure.

**5.** (10 points) What hardware is required to test whether one 32-bit
quantity is less than another? Sketch the general idea for a combinational
logic circuit that would take 32-bit, signed,
2's-complement, integer inputs *x* and *y* and
produce a 1-bit output *x<y*. You do not need to draw all the gates;
just be clear about what is required.

**6.** (5 points) Draw a gate-level circuit for
*x>=0* (where *x* is
32-bit, signed, etc., etc.).

**7.** (10 points) Problem 3.30 from the text.

**8.** (10 points) Problem B.14 from the text.

**9.** (5 points) The textbook authors (and their publisher)
would like you to fill out a short questionnaire for each chapter.
The chapter 1 questionnaire may be found at
http://www.cs.princeton.edu/courses/cs471/chap1.txt.
Please fill it out
and e-mail the result to the publisher as directed.
Your answers to this and future questionnaires will greatly help
the authors improve their book. Please do not, repeat *not*,
``cc your instructor on this email,'' as the form directs.
To get the 5 points for this question, just write down the time
you sent your message to the publisher.

**10.** (another 5 points) Same deal for Appendix B; find the
questionnaire at
http://www.cs.princeton.edu/courses/cs471/B.txt.

**11.** (1 point) How long did this take you, not counting the reading,
and with whom did you work?