Answers to Selected Problems on Synchronous Sequential Logic(See Chapter 6 of Mano's Digital Design (2nd ed.))
6-1 Construct a D flip-flop that has the same characteristics as the one shown in Fig. 6-5, but instead of using NAND gates, use NOR and AND gates.
6-2 Construct a D flip-flop that has the same characteristics as the one shown in Fig. 6-5, but instead of using NAND gaates, use NOR gates.
6-3 The D flip-flop shown in Fig. 6-5 can be constructed with only four NAND gates. Draw the modified circuit and show that it operates the same way as the original circuit.
6-17 Substitute binary assignment 2 of Table 6-8 to the states in Table 6-7 and obtain the binary state table. Repeat with assignment 3.
6-18 Analyze the circuit shown below and prove that it is equivalent to a T flip-flop.
Construct a truth table for D, with T and Q(t) as inputs. Then use the characteristic table of a D-type flip-flop to form the fourth column of this table for Q(t+1). Now if we discard the column headed by D, the resulting table is identical to the characteristic table of a T-type flip-flop. Thus the proof.
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