University:
California State University, Northridge
Course:
COMP 122 | Computer Architecture and Assembly Language and Lab
Academic year:

2022
Views:

27

Pages:

4
Author:

NyiH

2. Design a counter with the following binary sequence: 1, 2, 5, 7 and repeat. Use JK flip-flops. Solution: Step 1: Since it is a 3-bit counter, the number of flip-flops required is three. Step 2: Let the type of flip-flops be JK flip-flops. Step 3: Let the three flip-flops be A,B,C. Step 4: The state table is as shown in Table 2.1. Table 2.1: State table Present State Next State 001 010 10 1 11 1 010 101 111 001 ABC ABC Step 5: The next step is to develop an excitation table from the state table, which is shown in Table 2.2. Table 2.2: Excitation table Output State Transitions Next State Present State I ABC 001 010 10 1 11 1 I I ABC 010 1 01 1 11 001 Flip-flop Inputs I JAKA 0 X 1 X X 0 X 1 JBKB 1 X X 1 1 X X 1 NOTE: There are states that are not filled. For example 000 is not in the table. When you enter in the KMap, you will have empty cells. Those cells are ZERO JCKC X 1 1 X X 0 X 0