CS 152 Homework 1

Homework 1 is due Wednesday 9/10 at 5:00pm in the box in 283 Soda. Please include the TIME and TA NAME of the DISCUSSION section that you attend as well as your NAME, STUDENT ID and LOGIN. Homeworks and labs will be handed back in discussion sections.

Homework Policy:

1. No late homeworks will be accepted.
2. You may discuss problems with your friends, but all work must be done individually and you must be able to prove that you understand everything that you hand in.
3. If we can't read it from 2 feet away, we won't grade it.

Homework #1:

Unless otherwise noted, all questions refer to the Beta version of COD.

Questions 1.51-3, 3.17, 3.29, 3.30 are located in the old (2nd Edition) of COD. We have scanned the relevant pages and made them available here but only to machines on the Berkeley network.

• 1.51-3 (See scanned photos: Pg. 48-50)
• 2.3
• 2.12
• 2.18
• 2.19
• 2.22
• 2.25
• 3.9 UPDATE: The code snippet given in this question should read as follows:
  while(save[i] == k)
  i += 1;
• 3.10
• 3.17 UPDATE: The scanned photo from the old book instructs you to look at figure 3.38 on page 189. Instead look at figure 3.57 on page 216 of the new book. (See scanned photo: Pg. 201)
• 3.29, 3.30 (See scanned photo: Pg. 206)
• B.15, B.21, B.22 (located below)

B.15: Construct the truth table for a four-input even-parity function. TA Note: An even-parity function is one that counts the number of ones in the input and outputs a 1 if there are an odd number of 1s in the input and a 0 if there are an even number of 1s in the input.

B.21: A friend would like you to build an "electronic eye" for use as a fake security device. The device consists of three lights lined up in a row, controlled by the outputs Left, Middle, and Right, which, if asserted, indicate that a light should be on. Only one light is on at a time, and the light "moves" from left to right and then from right to left, thus scaring away thieves who believe that the device is monitoring their activity. Draw the graphical representation for the finite state machine used to specify the electronic eye. Note that the rate of the eye's movement will be controlled by the clock speed (which should not be too great) and that there are essentially no inputs.

B.22: Assign state numbers to the states of the finite state machine you constructed for Exercise B.21 and write a set of logic equations for each of the outputs, including the next state bits.