ECS154A Homework #3

• All parts of the homework due by 4:30 PM on Wednesday, February 4th
  NOTE - no late days on this assignment. No homeworks will be accepted after the deadline.

Assignment (Written):

1. Do Problem 8.2 in the book (use SR instead of JK FF's)
2. Do Problem 8.5 in the book, detecting 101 or 011 patterns
3. Do Problem 8.6 in the book, detecting 101 or 011 patterns
4. Do Problem 8.11 in the book, detecting 0111 or 0101 patterns
5. Do Problem 8.12 in the book, only do it over 4 bits and make p=1 if the number of 1's is even
6. Given the following information:

The propagation delay through a DFF is 8ns
The setup time for a DFF is 3ns
The hold time for a DFF is 2ns
The delay through an AND gate is 4ns
The delay through a MUX is 5ns
X, Y and SEL are fixed and do not change

Find the worst case path through the following circuit.

Assignment (MaxPlus):

1. Do Problem 8.27 in the book.

2. Consider a coin-operated vending machine. Assume that the
   machine accepts only quarters, dimes, and nickels. Coins are inserted 
   until a total of 25 cents or more is deposited. Only 
   one coin is deposited at a time. The output signal z1=1 should indicate 
   that merchandise should be provided; z1=0 indicates no merchandise.
   
   Coincident with the last coin input, the (change) outputs are to be set.
   Assume the machine can give a dime (z2=1) and/or a nickel (z3=1).
   Use the binary outputs z2 and z3 to represent the 4 distinct possibilities
   (No change, 1 nickel, 1 dime, 1 nickel and 1 dime.)  If a customer does
   something unwise, like puts in a dime and a nickel followed by a quarter, 
   correct change does not have to be provided (but the maximum amount change 
   does.)
   
   Design the circuit in Maxplus.