Practice Test Answers

These are just the answers, sorry, I don't have time for a full
solution...


3.) a, d, e.   x'z' would also have been correct.


4) a and b.  (d) would have been right if the first "y" wasn't missing
a prime.


5.) c and d

6.) Start with 5(c), draw normally, replace ORs with NORs, ANDs with
invert-ANDs, and add inverters appropriately.  
Alternatively, map the function, change to MPOS, and get a smaller
circuit.  Either is fine, I didn't say anything about being
efficient...

8.)  Either F = x'z' + y + w'x
or F = x'z' + y + w'z' is acceptable

b.) F=(wxy'+y'z)'

10.) Add 2 or gates to the output of the decoder.  Connect outputs 
1,3, and 5 to one and mark it as F, connect 0,1, and 4 to the other
and mark it G.

b.) Hook a,b, and c to the inputs, mark the top output F and mark
fuses 1,3, and 5, mark the bottom output G and mark fuses 0,1, and 4


11.) 
Equations:
F = x'y + xy'
G = y'

12) a.) use a 4x1 mux.  Hook the select lines to y and z.  Hook
inputs 1 and 2 to x and 2 and 3 to x' .  The output if F.

b.) Mark the fuses on the PAL diagram to implement the equations in
11. (G involves closing just 1 fuse on 1 and gate!)