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Step of 4 7.22DP Refer Figure 7-58 from the textbook. Using the figure, the transition list is obtained as shown in table 1. RARB RA'RB' S LALBLC Tranisition equation RC LC' IDLE 000 000 IDLE 000 000 IDLE 000 000 L1 001 000 IDLE 000 000 HAZ' LR3 111 111 IDLE 000 000 HAZ R1 000 100 L1 001 000 HAZ' L2 011 000 L1 001 000 HAZ LR3 111 111 L2 011 000 1 L3 111 000 L2 011 000 HAZ' LR3 111 111 L3 111 000 HAZ IDLE 000 000 R1 000 100 HAZ' R2 000 110 R1 000 100 HAZ LR3 111 111 R2 000 110 1 R3 000 111 R2 000 110 1 LR3 111 111 R3 000 111 IDLE 000 000 LR3 111 111 IDLE 000 000 Table 1 Step of 4 Using the = terms where and the transition table in Table 1, the transition equations are as follows: = = +LA'-LB'-HAZ = = Step of 4 The design can be done using two 74x138s and a combinational logic as shown in Figure 1. +5V LC LC* +5V RA Figure 1 Step of 4 In the Figure 1 he Top 74x138 is used decode the states of LA, LB and LC. The Bottom 74x138 is used decode the states of RA, RB and RC. The combinational logic is used to develop the functional requirements and are buit based on the derived transition equtions.