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Step of 8 7.055E Refer to Table 7-11 from the textbook for the state and output table for combination-lock machine. Consider a fact that the inputs 1 to 3 are the same as inputs 4 to 6 in the required input sequence. Consider the following expressions for D1, D2, D3, UNLK and HINT from the textbook: Step of 8 Assign 3-bits for the states of the combination-lock machine that results in less costly excitation equations than the ones derived in the text. Table 1 Y1Y2Y3 X 0 1 011 111,01 011,00 111 111,00 000,01 000 111,00 001,01 001 110,01 011,00 110 111,00 010,01 010 111,00 100,01 100 110,00 101,01 101 111,11 011,00 Step of 8 Derive the exciataion equations using the transition list from the Table 1 and Karnaugh maps. Find the exciataion equation for D1. Q3X QIQ2 00 01 11 10 1 1 TO 11 1 11 1 1 10 11 1 Figure 1 Step of 8 Derive the expresion from Figure 1. Step of 8 Find the exciataion equation for D2. Q3X 00 01 11 10 00 1 1 1 to 1 1 1 11 11 1 . 10 1 11 Figure 2 Step 6 of 8 Derive the expresion from Figure 2. Step of 8 Find the exciataion equation for D3. Q3X 00 01 11 10 1 1 1 01 1 1 1 11 1 1 10 1 1 1 Figure 3 Step 8 of 8 Derive the expresion from Figure 3. The system requires six 3-input gates, four 2-input gates and two 4-input gates. Thus, the system is less costly than the system in the text book.