CPE/EEE 064 Introduction to Logic Design - Fall 2003
Dr. Jing Pang
Quiz 4
Sequential Circuit
1. Please fill out the following Flip-Flop Excitation Tables and explain how to use
them in the sequential circuit design. Please write the characteristic equations of
JK Flip-Flop, SR Flip-Flop, D Flip-Flop and T Flip-Flop.
JK Flip-Flop
Q(t)
Q(t+1)
0
SR Flip-Flop
J
K
Q(t)
Q(t+1)
0
0
0
0
1
0
1
1
0
1
0
1
1
1
1
D Flip-Flop
Q(t)
Q(t+1)
0
2.
S
R
T Flip-Flop
D
Q(t)
Q(t+1)
0
0
0
0
1
0
1
1
0
1
0
1
1
1
1
T
Please draw a state diagram for the following state table and use rising edge
triggered D Flip-Flops to implement the state table below. Complete the
waveform below.
Present State
Q0(t)
Q1(t)
0
0
0
0
0
1
0
1
1
0
1
0
1
1
1
1
Input
X
0
1
0
1
0
1
0
1
Next State
Output
Q0(t+1) Q1(t+1)
Y
0
0
0
0
1
0
0
0
1
1
1
0
0
0
1
1
0
0
0
0
1
1
0
0
CLK
X
Q0
0
Q1
0
3. Please use JK Flip-Flops to implement the state table below.
Present State
Q0(t)
Q1(t)
0
0
0
0
0
1
0
1
1
0
1
0
1
1
1
1
Input
X
0
1
0
1
0
1
0
1
Next State
Q0(t+1) Q1(t+1)
0
1
0
0
1
1
1
0
1
1
1
0
0
0
1
1
CLK
X
Q0
0
Q1
0
4. (1).
(2).
(3).
Design a T Flip-Flop using a JK Flip-Flop.
Design a T Flip-Flop using a D Flip-Flop.
Complete the following waveform for a T Flip-Flop circuit.
5. (1).
(2).
Design a D Flip-Flop using a JK Flip-Flop.
Design a JK Flip-Flop using a D Flip-Flop.
6. Design sequential circuits with D Flip-Flops to implement the following state
diagram.
0/0
1/1
1/0
00
1/0
01
11
0/0
0/0
1/1
10
0/0
7. Design sequential circuits with D Flip-Flops to implement the following state
diagram.
01,10
00,11
0/0
1/1
01,10
00,11
8. A sequential circuit shown below has two JK Flip-Flops, one input X, and one
output Y. Derive the state table and state diagram of the circuit.
J
CLK
Q
C
K
J
Q
B
C
K
B
X
Y
9. Use D Flip-Flop to design a circuit that recognizes the occurrence of a sequence
“1101”, regardless of where it occurs in a long sequence. Write Verilog program
and complete the following waveform for this sequence recognizer (Q0 and Q1
represent two states, X is input and Z is output).
CLK
X
Q0
0
Q1
0
Z
0
10. Please draw a two-bit Shift Registers with parallel lode circuit using D Flip-Flops.
Write the function table and draw the waveform to explain the function of this
circuit. Write Verilog program for this circuit.
11. Design a circuit to implement 4-bit synchronous binary counter using D FlipFlops. This circuit should be controlled by the enable signal “EN”. Write
structural Verilog program for the circuit you designed.
12. Design a circuit to implement 4-Bit synchronous binary counter with parallel load
using D Flip-Flops. Write structural Verilog program for the circuit you designed.
13. Design a BCD counter using the above 4-Bit synchronous binary counter with
parallel load circuit you designed. What change do you need to make if you want to
count from 0011~1111?
14. Please analyze the following circuit. What are the functions of signal A and B?
15. (1)
You only have D-Flip Flops with asynchronous preset and reset.
(1) Design 2-Bit shift register with synchronous parallel load using D FlipFlops.
(2). Design 2-Bit shift register with asynchronous parallel load using D FlipFlops.
16. Draw the circuit of a 4-Bit Register with Parallel Load circuit using D Flip-Flops.
Write Verilog for your circuit.
17. Design a BCD synchronous counter using T Flip-Flops.
18. Design a 4-bit binary synchronous counter with parallel load using JK Flip-Flops.
19. Draw a 4-bit asynchronous ripple UP-Counter circuit using JK Flip-Flops.
20. Draw a 4-bit asynchronous ripple Down-Counter circuit using JK Flip-Flops.
21. Use T Flip-Flops to design a synchronous counter with the following repeated
binary sequence: 0, 1, 3, 2, 4, 6.
22. Use D Flip-Flops to design a synchronous counter with the following repeated
binary sequence: 0, 1, 2, 4, 8.
23. What is the function of following circuit? Draw the waveform to explain your
analysis.
24.
Complete
the waveform for the following circuit and explain the function of this circuit.
25. Please design a two-bit BCD counter using two one-bit BCD counters. You can
use any necessary extra combinational logic circuits.
26. The following circuit consists of 9 D Flip-Flops and a one-bit full adder. Please
complete the following waveform and explain the function of this circuit.