ELET 3132: Practice Midterm Exam
Name:_____________________
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1. Convert the following binary, decimal, or hexadecimal numbers to the other two numbers systems.
Fill in all the blanks
Binary
01110001
Decimal
-1
65
Hexadecimal
41
2. Draw the output waveform for f given the circuit and input waveforms shown below.
f
3. Draw the output waveform for f given the circuit and input waveforms shown below.
f
4, 5, 6. The following 3 logic expressions must be reduced to their minimum SOP form. One must be
minimized using Boolean algebra, one must be minimized using Karnaugh maps, and one may be
minimized in any way you want. You must show your work
4. f = A BC + AB C + ABC + BC
f=_______
5. f = AB + AB + A C
f=_______
6. f = A B C + A B C + ABC + ABC
f=_______
Figure 1: VHDL Code #1
7. Sketch the Entity (the Black Box) and show the truth table for the VHDL code in Figure 1.
f = ABC + AB + ABC + ABC
Figure 2: Expression for problems 9-11
8. Implement the expression in Figure 2 using basic logic gates. Sketch the circuit. Do not minimize the
expression.
9. Sketch the circuit for the expression shown in Figure 2 using an 8-to-1 multiplexer.
10. Sketch the circuit for the expression shown in Figure 2 using a 4-to-1 multiplexer.
11. Assume the waveforms in figure 3 are the signals on the inputs of the decoder and that the outputs
are initially low. Draw the output waveforms on the diagram below.
Figure 3: Input Waveforms for problems 12
12. Assume the waveforms in figure 4 are the signals on the inputs of the 4-bit adder and that the
outputs are initially low. Draw the output waveforms on the diagram below.
Figure 4: Input Waveforms for problems 12
13. Assume the waveforms in figure 5 are the signals on the S and R inputs of the flip-flop and that Q is
initially low. Draw the Q output on the diagram below.
Figure 5: Input Waveforms for problems 13
14. Assume the waveforms in figure 6 are the signals on the D input of the flip-flop and that Q is initially
low. Draw the Q output on the diagram below.
Figure 6: Input Waveforms for problems 14
15. Assume the waveform in figure 7 is the signal on the D input of the flip-flop and that Q is initially
low. Draw the Q output on the diagram below.
Figure 7: Input Waveforms for problems 15
16. Assume the waveform in figure 8 is the signal on the D input of the flip-flop and that Q is initially
low. Draw the Q output on the diagram below.
Figure 8: Input Waveforms for problems 16
17. Assume the waveform in figure 9 is the signal on the T input of the flip-flop and that Q is initially low.
Draw the Q output on the diagram below.
Figure 9: Input Waveforms for problems 17
18. Assume the waveforms in figure 10 are signals on the J and K inputs of the flip-flop and that Q is
initially low. Draw the Q output on the diagram below.
Figure 10: Input Waveforms for problems 18
19. What does the “HDL” stand for in the acronym “VHDL”: (V): Very High Speed Integrated Circuit:
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